Final Report Summary - VIVAC (Viscogel - A chitosan based adjuvant for prophylactic and therapeutic vaccination)
Executive Summary:
Safe and efficient prophylactic vaccines are still lacking for a number of infectious diseases. Moreover therapeutic vaccines to e.g. cancer, autoimmune diseases or allergy, constitute an emerging area of interest. The effect of a vaccine can be enhanced by adjuvants, which are also able to direct the type of immune response elicited. Thus novel adjuvants have the potential to improve prophylactic and therapeutic vaccines.
In the VIVAC project the overall objective was to develop and to show safety and efficacy for a new innovative carbohydrate (chitosan) based adjuvant - ViscoGel - to be used both in prophylactic and therapeutic vaccination. For prophylactic vaccination a model vaccine to Heamophilus influenzae type b (causing bacterial meningitis), Act-Hib, was used to show preclinical and clinical proof of concept (POC).
For therapeutic vaccination the target was allergy vaccination using the major birch pollen allergen Bet v1. In addition an immune- and permeation- enhancing peptide, LTX-315, was evaluated, since mucosal allergy vaccination through the sublingual route was specifically addressed. Three SMEs (Viscogel AB, SE; Lytix Biopharma AS, NO; Inmunotek SL, ES) provided their background technologies to the project: ViscoGel manufacturing, LTX-315 and recombinant as well as natural purified Bet v 1.
Research and technical development (RTD) activities were performed to reach the project goals. Extensive formulation work was carried out including design, development and characterization of chitosan and ViscoGel formulations. A number of activities focused on the development of a clinical ViscoGel product for prophylactic vaccination. Preclinical characterization of ViscoGel-Act-Hib led to the identification of a ViscoGel clinical product candidate that was subjected to extensive characterization, process development and GMP production. Toxicity evaluation of ViscoGel and ViscoGel-Act-Hib was carried out in two species. The compiled preclinical documentation on ViscoGel formed the basis for regulatory and ethical approval to perform a clinical Phase I/IIa trial to show POC for prophylactic vaccination.
The clinical trial evaluated safety and efficacy of one intramuscular injection of ViscoGel alone and as adjuvant for Act-Hib. RTD on ViscoGel formulations for allergy vaccination followed two lines, development of vaccines for subcutaneous (SCIT) and for sublingual (SLIT) allergen specific immunotherapy/vaccination. The target was birch pollen allergy and the major allergen Bet v 1. Mouse experiments were performed to find promising Bet v 1 SCIT candidates formulated with ViscoGel. A mouse model for birch pollen allergy and SLIT was established to obtain preclinical POC for ViscoGel as an adjuvant in SLIT. Experiments to identify SLIT candidates were performed with a model antigen, OVA, evaluating formulations containing OVA in chitosan solutions, with ViscoGel and with LTX-315. Finally a Bet v 1 SLIT candidate was tested in the SLIT model.
The most important result of VIVAC was the development of a clinical ViscoGel adjuvant product that was applied in a Phase I/IIa trial. Intramuscularly administered ViscoGel was shown to be safe and well tolerated in man. Subgroup efficacy analyses revealed a positive adjuvant effect of ViscoGel. These results are of critical importance for the exploitation of ViscoGel as adjuvant in human vaccines. For therapeutic vaccination useful data were obtained on formulation of ViscoGel based allergy vaccines intended both for SCIT and for mucosal vaccination, which will support further developmental work.
In conclusion, VIVAC has provided an innovative platform for development of ViscoGel as adjuvant in prophylactic and therapeutic vaccines. The project has generated new foreground and potential new collaborations for the benefit of the participating SMEs. In VIVAC, ViscoGel was proven to constitute a simple, safe and versatile adjuvant system applicable for human use. In a wider perspective, such an adjuvant system may provide solutions to current challenges in the development of therapeutic vaccines to e.g. cancer, autoimmune diseases and allergy, as well as for the development of vaccines to infectious diseases to which efficient protection cannot be provided with present vaccines.
Project Context and Objectives:
There is a huge global demand for new vaccines able to elicit efficient and appropriate immune responses to infectious agents (prophylactic vaccines) as well as vaccines capable to modify pathogenic immune responses (therapeutic vaccines). Suboptimal vaccines may be improved by adjuvants, i.e. enhancers of the immune response. Adjuvants also provide means to modify an immune response and direct it towards a specific functional response. The route of administration is known to affect the immune response stimulated and, in addition, adjuvants can be designed to act as vehicles or delivery systems for vaccine administration, e.g. for mucosal vaccines. Only four adjuvants in total have been licensed in the EU and US. There is therefore a significant opportunity for new adjuvants and vaccine technologies, as vaccine design has focused on highly purified antigens with limited efficacy.
In the VIVAC project the overall objective was to develop and to show safety and efficacy for a new innovative carbohydrate (chitosan) based adjuvant - ViscoGel - to be used both in prophylactic and therapeutic vaccination.
Specific objectives set up for VIVAC:
1) to develop analytic tools for quality assessment of ViscoGel preparations and provide building blocks for formulations;
2) to characterize and optimize chitosan gel systems with controllable biodegradation and mucoadhesive properties;
3) to provide GMP-produced ViscoGel formulated with Act-Hib for clinical application;
4) to investigate the nature of the immune response to antigens administered with ViscoGel and if the co-formulation with LTX-315 can enhance the adjuvant and epithelial penetrating capacity
5) to provide formulations of ViscoGel with Bet v 1, with LTX-315 and with both Bet v 1 and LTX-315 intended for preclinical application;
6) to show POC for prophylactic vaccination using ViscoGel formulated with Hib and to demonstrate preclinical and clinical safety;
7) to show POC for therapeutic vaccination using ViscoGel formulated with Bet v 1 in relevant preclinical sub-lingual immunotherapy (SLIT) and subcutaneous immunotherapy (SCIT) models for treatment of birch pollen allergy;
8) to develop new and increased IP protection for candidate ViscoGel formulations; and
9) to obtain the documentation needed for clinical development and commercialisation.
Three SMEs participated in the VIVAC project and contributed with their expert competences:
1) Viscogel AB, Sweden, provider of the ViscoGel technology;
2) Lytix Biopharma AS, Norway, provider of peptide technology and LTX-315; and
3) Inmunotek SL, Spain, provider of Bet v 1.
To achieve the VIVAC project goals, the following activities have been performed:
1) Development and production of ViscoGel formulations, including development of a ViscoGel manufacturing process according to GMP.
2) Characterisation of chitosan and gels; assessment of physicochemical, mucoadhesion and permeation properties.
3) Preclinical characterisation and POC of ViscoGel as adjuvant for prophylactic vaccination to Hib.
4) Toxicology evaluation and clinical trial to obtain safety data and show POC for ViscoGel in man.
5) In vitro and in vivo characterization of ViscoGel preparations for SLIT application, establishment of a mouse model for sensitization to birch pollen allergen, and evaluation of candidate vaccines.
6) In vivo characterization of ViscoGel preparations with recombinant and natural Bet v 1 for SCIT application.
7) Management and dissemination of project results.
Project Results:
Introduction
The overall objective of VIVAC was to develop and show proof of concept (POC) for ViscoGel as a novel adjuvant for prophylactic and therapeutic vaccination. An overview of the results of VIVAC shows that the objective has been fulfilled for prophylactic vaccination, showing safety and efficacy for ViscoGel as adjuvant in man. For therapeutic vaccination useful data have been obtained for the use of ViscoGel as adjuvant, but POC was not obtained for this application. The project results will here be presented as reports of the individual milestones set up for VIVAC, followed by a summary description of the main S&T results/foregrounds of the project.
Milestone 1: Recombinant and natural Bet v 1 for formulation with ViscoGel
The objective of Milestone 1 was to provide recombinant and natural Bet v 1 for formulation with ViscoGel early in the project. One hundred mg of recombinant (r)Bet v 1 and 200 mg of natural (n)Bet v 1 were delivered on time from Partner 3, Inmunotek SL, to Partner 1, Viscogel AB. It was important to show that both the rBet v 1 and the nBet v 1 purified from birch pollen extract were of high quality and, most importantly, that they possessed retained allergenicity. This was shown by analysis of binding to patients' IgE.
Milestone 2: LTX peptide for formulation with ViscoGel
LTX-315 was synthesised by Bachem AG, Bubendorf, Switzerland, on commission of Partner 2, Lytix Biopharma AS. One gram of the synthetic LTX-315 peptide, LTX-315 Acetate batch 1015058, was delivered on time to Partner 3, Viscogel AB, together with a declaration on physico-chemical characteristics of the product.
The objective of Milestone 2 was to provide LTX-315 to the project. This was also the objective of WP2, with Partner 2, Lytix Biopharma, as lead beneficiary.
Milestone 3: ViscoGel formulations with Hib, Bet v 1 and LTX-315 for preclinical applications
Milestone 3 served as a checkpoint for providing formulations for prophylactic and therapeutic vaccine design and preclinical testing. The development and production of chitosan, Viscosan and ViscoGel preparations with different properties was carried out by Partner 3, Viscogel, from the start of the project and continued after the delivery date of Milestone 3 at month 9.
ViscoGel formulated with rBet v 1 and nBet v 1 was produced together with control test material and was delivered to Partner 3, Inmunotek, for application in mouse SCIT experiments (WP8). For the last experiment rBet v 1 was also covalently linked to ViscoGel in order to assess if physical linkage between antigen and ViscoGel enhanced, or possibly modified, the immune response induced.
Based on the results from the evaluation of these formulations using OVA, a candidate Bet v 1 vaccine was designed, where rBet v 1 was formulated by mixing the allergen in a Viscosan solution. Results of screening experiments for SLIT, as well as the POC-experiment in the Bet v 1 SLIT model are described below in the Milestone 12 report.
Milestone 4: Description of chitosan and gel properties, as well as stability and antigen release data
The major results of WP4 are given here as a report on Milestone 4. The aim of this milestone was to investigate the suitability of ViscoGel as a vehicle for antigens in vaccine design. The method development and results obtained in WP4 were of importance for compiling an Investigational medical product dossier (IMPD) for Viscosan/ViscoGel. Partner 4, NTNU, was the lead beneficiary in WP4.
Overall conclusions
Characterisation of Viscosans has successfully been carried out applying proton NMR spectroscopy, intrinsic viscosity measurements and SEC-MALLS. Even though the characterisation of ViscoGel systems, both in terms of bulk properties and particulate gel stability, was found to be unexpectedly challenging, the methods used for their characterization in this report seem to provide the necessary information.
The results obtained in this WP regarding the Viscogel properties confirm the appropriateness of ViscoGel as an administration form for the presentation of antigens. The gels are very stable under sterile conditions suggesting that antigen-containing products can be manufactured and stored for a prolonged period of time. Furthermore, the obtained results also suggest that ViscoGels can be tailored to meet specific demands with respect to biodegradability and hence also specific antigen properties.
Milestone 5: Characterisation of Viscogel-formulation for SLIT
This Milestone was dedicated to studies on mucoadhesion and permeability characteristics of Viscosan and ViscoGel preparations. The aim was to gain information that could guide the design of allergen-ViscoGel/Viscosan formulations for SLIT application. The activities linked to Milestone 5 were performed by Partner 5, Hacettepe.
Mucoadhesion
The mucoadhesion studies were performed on bovine buccal tissue freshly obtained from the slaughterhouse. The epithelial tissue was separated from the connective tissue. Mucoadhesion was assessed with a Texture Analyser using a mucoadhesive rig. The force needed to detach the test formulations was recorded as a function of elongation and both maximum strength and area under the force/time curve was obtained. The results were converted into work of adhesion (mJ).
The adhesion was found to be significantly increased with increased contact time. Increasing the contact time provides interdiffusion and chain entanglement between polymer and mucin chain in mucus membrane. Extending the contact time between mucoadhesive polymer and mucosa causes secondary bond formation, increasing the mucoadhesive strength.
Mucoadhesion was found to be affected by the viscosity of the test preparations, showing a positive correlation between viscosity and mucoadhesion (i.e. increased viscosity corresponded to increased mucoadhesion.
Evaluation of the mucoadhesion of Viscosan with different viscosity, DD and concentrations, with or without ViscoGel particles, revealed that only the viscosity had a significant impact on mucoadhesion. The presence of TEO or OVA affected the mucoadhesive properties, indicating that the physicochemical properties of a formulated compound, such as solubility, molecular weight etc., have to be taken into account when evaluating mucoadhesion of a Viscosan/ViscoGel formulation.
Mucosal permeability
Freshly obtained bovine buccal mucosa from the local slaughterhouse was used as a model for the non-keratinized human buccal mucosa. The underlying tissue was removed from the mucosa, and then the epithelium was separated from most of the connective tissue with the help of scalpel.
An effect was detected for viscosity (increased permeation with decreased viscosity), DD (decreased permeation with decreasing DD) and presence of ViscoGel particles (lower permeation for Viscosan with ViscoGel particles, compared to without particles), while concentration had no effect on permeation. With the commercially available chitosans, lower permeation was obtained compared to that of the Viscosans. The permeation profiles obtained for OVA was affected by DD (increased permeation with increasing DD), whereas no significant effect was obtained with viscosity and concentration. Presence of ViscoGel particles in the chitosan preparation was found to increase the permeation of OVA.
The permeability coefficients were calculated from the steady state of the permeation curves and comparison of the permeability coefficients of TEO and OVA revealed that permeability of TEO formulations was higher than that of OVA formulations. Higher permeability coefficients were obtained with high viscosity samples.
Permeability studies of different chitosan and viscosan preparations, with and without ViscoGel particles, formulated with the small drug theophylline (TEO) or the high molecular weight OVA revealed different patterns for the two model compounds. Generally permeation was lower for OVA than for TEO.
General conclusion
The mucoadhesion and permeation studies were performed with chitosan solutions with different physicochemical characteristics. Viscosity was the only property that affected mucoadhesion, but viscosity had opposite effects on permeation of TEO and no effect on permeation of OVA. It was found that incorporation of drug into chitosan preparations (model compounds TEO or OVA) affects mucoadhesion and permeation. Model compounds with similar characteristics to a test compound (e.g. protein nature, MW) could potentially generate useful data in this kind of studies, but the actual compound to be tested has to be evaluated. In VIVAC the mucoadhesion and permeation studies were meant to be performed for guidance of formulation design for SLIT studies with Bet v 1. Due to initial difficulties to apply the chitosan formulations in the mucoadhesion- and permeation assay systems and the demand for huge amounts of test substances, it was not feasible to perform these experiments with Bet v 1 within the given time frame. Thus the results obtained in WP5 could not be used for guidance when designing SLIT formulations for WP8.
Milestone 6: Preclinical characterisation and POC for prophylactic vaccination (ViscoGel-Hib)
The objective of Milestone 6 was to conclude the preclinical characterisation of ViscoGel as an adjuvant for prophylactic vaccination. Moreover preclinical data were obtained in mice to guide the selection of ViscoGel formulation for the clinical POC study. In the clinical trial of ViscoGel as adjuvant a model vaccine to Haemophilus influenzae type b, Act-HIB, was planned to be used and thus most preclinical evaluations were performed with Act-Hib. The results also formed the basis for the documentation in order to obtain all regulatory permissions to ensure that the clinical trials could be conducted. Here the results leading to selection of the formulation to be used in the clinical trial are briefly described.
A report has been published based on the studies related to Milestone 6 (Neimert-Andersson et al. (2011) Vaccine 29:8965). The activities were linked to WP7 and Karolinska Institutet was the lead beneficiary. The next aim was to characterize the immune response to Act-Hib when administered to mice together with ViscoGel via the subcutaneous (s.c.) or the intramuscular (i.m.) route, with the focus to provide data for the selection of ViscoGel formulation for the clinical POC study.
The local immune response to ViscoGel was investigated. When characterizing a novel adjuvant, it is of interest to compare it to a well-known adjuvant. The most widely used adjuvant is aluminium salts (alum). Alum is used both in experimental settings and until recently it was the only adjuvant approved for human vaccines. Therefore ViscoGel was compared to alum. Results indicate ViscoGel to be a superior immunostimulant compared to alum.
Conclusion
From the preclinical studies performed in WP7, we can conclude that ViscoGel is a potent adjuvant, superior to the established adjuvant alum, resulting in enhanced humoral and cellular responses when administered both subcutaneously and intramuscularly. The best effect was obtained with larger ViscoGel particles (200 µm) used together with Act-HIB. The 200 µm particles were used to characterize the cellular infiltration when administered both subcutaneously and intramuscularly. The results indicate that the primary action taking place locally is the rapid infiltration of granulocytes (neutrophils and eosinophils), which then can induce rapid, within three weeks complete, degradation of ViscoGel. The recruited neutrophils may interact with dendritic cells for priming of the adaptive branch of the immune system, resulting in a strong immune response.
A report presenting preclinical POC for ViscoGel as adjuvant for Act-Hib has been published:
Neimert-Andersson T., et al. 'Improved immune responses in mice using the novel chitosan adjuvant ViscoGel, with a Haemophilus influenzae type b glycoconjugate vaccine' Vaccine, (2011) 29:8965-73
Milestone 7: ViscoGel-Hib of GMP grade for clinical use
Based on the preclinical characterisation of ViscoGel as an adjuvant for the model vaccine Act-Hib, a ViscoGel to be formulated with Act-Hib was GMP produced for the clinical trial. A summary of the GMP production of ViscoGel, as well as a description of the ready to use kit with Act-Hib for the clinical trial is given here. Partner 1, Viscogel, was responsible for these WP3 activities.
GMP-produced ViscoGel
The entire process, spanning from manufacturing of chitosan (Viscosan) to release of a final test article for clinical use involved many steps, the most important being:
a) Establishment of product specifications for raw materials and products.
b) Implementation of a quality system for manufacturing of Viscosan (GMP compliant).
c) Manufacturing of Viscosan (50% DD).
d) Technology transfer and manufacturing of ViscoGel and ViscoGel particles at a GMP-approved Contract manufacturing Organisation (CMO).
e) Selection of packing materials and labelling.
f) Release of test material for clinical study.
g) Regulatory approval for clinical plan from the Swedish Medical Product agency (MPA) and from the local ethical committee.
In brief, early and very basic observations made us focus on the manufacturing of chitosan with a DD of 50%. Based on a large amount of experimental work, protocols for an efficient removal of endotoxins and protein impurities were identified. These results and information in European Pharmacopeia was the basis for setting limits for impurities in Viscosan and lead to a tentative product specification for Viscosan. The next step was to establish a quality system for the manufacturing of a starting material for the pharmaceutical industry that could meet the industrial standards. In brief, we implemented a GMP-compliant quality system for our manufacturing of Viscosan. A chemical process could then be developed for Viscosan, which meets the common goals normally used for industrial processes, i.e. a process that gives a consistent batch quality, has a low cost of goods (COGS), is scalable and that produces waste streams of low toxicity and a low environmental impact. Manufacturing of approved Viscosan batches for toxicology-, stability and clinical studies went according to plan and these Viscosan batches all met the targets set.
ViscoGel-Hib for clinical use
The product for the clinical trial consisted of ViscoGel in combination with the commercial vaccine, Act-Hib from Sanofi Pasteur MSD. The vaccine was designed to be intramuscularly injected after a bedside mixing procedure in which the vaccine, dissolved in a buffer, was added to a sterile ampoule of ViscoGel particles suspended in Ringers acetate.
APL delivered one type of ViscoGel vial in a kit containing up to three buffer vials and one vial of lyophilized Act-Hib. This kit was specially designed to enable the clinical personnel to mix these vials in to one of eight different formulations through a randomization procedure. The final formulation is a 'bedside preparation' that is prepared just before injection. Eight different kits were prepared in advance for the eight groups planned to be included in the clinical trial (clinical trial design described in Milestone 9). Careful measures were taken to assure exact and reproducible handling by the clinical trial personnel, in order to keep the doses exact and to avoid adherence to the walls of the glass vial.
Conclusion
A fully GMP compliant batch of ViscoGel was produced and a patient kit including all necessary vials packaged and delivered to the clinical trial unit on April 5, 2012.
Milestone 8: Toxicology study completed, toxicology evaluation report
The toxicity of ViscoGel, as well as for the formulated vaccine consisting of Act-HIB mixed with ViscoGel, was evaluated in mice and rabbits. Local and systemic toxic effects were carefully investigated after three intramuscular administrations of ViscoGel. A full toxicology report was filed by Partner 6, Huntingdon.
Conclusion
It is concluded that the three intramuscular injections of either ViscoGel or ViscoGel/Act-Hib vaccine, when compared to controls, did not elicit any systemic toxic effects. Treatment related changes were largely confined to the dose sites, with histopathological changes in the spleen and popliteal lymph nodes indicative of immunogenic stimulation. These findings indicated the presence of a local reaction at the injection sites and immunogenic stimulation, as expected from the pharmacological activity of the test articles, and not toxicity. Act-Hib vaccine take was confirmed by a positive antibody response but there was no CMI response.
The results of the toxicity studies performed in mice and rabbits did not reveal any systemic toxic effects caused by ViscoGel. The local reactions observed were linked to the immune stimulation induced by vaccination. An eight times higher dose than the start dose planned to be used in the clinical trial was considered to be safe in rabbits. The toxicity reports supported the application to the Swedish MPA and local ethics committee for permission to perform a clinical trial with ViscoGel and the ViscoGel/Act-Hib vaccine.
Milestone 9: POC in man for ViscoGel as adjuvant (for Hib), clinical trial result
Milestone 9 is dedicated to a Phase I/II POC clinical trial performed at a single centre, Karolinska Clinical Trial Alliance (KTA), Partner 9. The primary study outcome was safety of ViscoGel and secondary the adjuvant effect of ViscoGel mixed with Act-Hib for intramuscular vaccination was evaluated. The study was monitored and data processed and recorded by Partner 10, Pharma consulting Group (PCG).
Conclusion
The clinical trial performed in VIVAC has provided 'first in man' data on ViscoGel. Safety objectives were fully accomplished, while efficacy objectives could not be fully addressed due to unexpectedly high incidence of HIB exposure in the study population, leading to high base-line anti HIB antibody titers. However, subgroup analyses excluding subjects with the highest baseline anti-HIB titers (either the top half or top quartile) indicated a higher increase of anti-HIB antibody production in groups treated with ViscoGel. Importantly, preliminary data on the cellular response induced by ViscoGel point to a Th1-biased cell mediated response to Act-HIB with ViscoGel, while vaccination with Act-HIB alone seems to have an opposite effect on the cell-mediated response. The safety data and the positive data on efficacy provide a platform for further development of ViscoGel as an adjuvant for parenteral administration of human vaccines.
Milestone 10: Bet v 1-formulations in ViscoGel w and w/o LTX-315 for sublingual (SLIT) and subcutaneous (SCIT) allergen specific immunotherapy
The objective of Milestone 10 was to provide therapeutic Bet v 1 vaccine test formulations for preclinical characterisation and SLIT and SCIT POC studies. The formulations were provided by Partner 1, Viscogel, for activities in WP8 to be carried out by Partner 3, Inmunotek (SCIT), and Partner 8, Stallergenes (SLIT).
Test formulations for SCIT application
An initial experiment was performed at Viscogel (Partner 1) where ViscoGel formulations with covalently linked or mixed rBet v 1 were stored at +4oC for up to three weeks and then used for immunisation of mice. The immune response was compared to the response to rBet v 1 alone and to freshly prepared rBet v 1-ViscoGel. It was demonstrated that the rBet v 1-ViscoGel formulations were stable in terms of antigenicity when stored at +4°C for three weeks, irrespective to if rBet v 1 was coupled to or mixed with ViscoGel. Formulations for experiments aiming at characterising the immune response to subcutaneously administered rBet v 1 and nBet v 1 were then designed and produced. For the first experiments rBet v 1 and nBet v 1 (Bet v 1 enriched birch pollen extract fraction) were formulated with ViscoGel. For the last experiment rBet v 1 was also covalently linked to ViscoGel.
Test formulations for SLIT application
A main objective of VIVAC was to develop a ViscoGel-based allergy vaccine for SLIT with rBet v 1 and birch pollen allergy as target. The immunological mechanisms for successful SLIT are only partially understood and therefore the only way to confirm a functional SLIT vaccine formulation is to test it in an allergy model, where the candidate SLIT formulation is administered sublingually to sensitised mice.
However, allergy models and SLIT protocol are time- and resource demanding experiments. Therefore pre-screening of SLIT candidate formulations have to be done, identifying formulations with characteristics considered to be essential for a successful candidate.
The screening experiments were for technical reasons performed with the model antigen OVA instead of Bet v 1. Two sets of formulations were prepared. For the antigen uptake assays the formulations were prepared with fluorescently labelled OVA (OVA-Alexa Fluor 488) and for the T-cell activation studies the corresponding formulations were prepared with OVA. After evaluation of the screening experiments (see Milestone 12 below), a formulation of rBet v 1 in 0.2% Viscosan (50%DD) was prepared for a SLIT POC experiment in a mouse SLIT model.
Milestone 11: Preclinical POC for SCIT vaccination
The aim of Milestone 11 was to obtain data to support application of ViscoGel as adjuvant in SCIT with rBet v 1 and/or nBet v 1. The experiments focused on characterisation of the humoral and cellular immune response to parenterally administered Bet v 1 formulated with various ViscoGel preparations in order to find an optimal ViscoGel formulation for SCIT application. The activities were performed within WP8 by Partner 3, Inmunotek.
In conclusion, the immunisation with rBet v 1 and nBet v 1 showed that the immune response to both the recombinant Bet v 1 and the natural enriched allergen was enhanced by formulation with ViscoGel. Furthermore some interesting observations were made on subtle differences between the immune response generated by different administration routes (i.p. or s.c.) between responses to nBet v 1 and rBet v 1 and there were indications of a more Th1-skewed response generated by ViscoGel- than by alum-adjuvanted antigen. Taken together, the results support application of ViscoGel as a promising adjuvant for SCIT.
The data suggest that the allergen, which could be rBet v 1 or nBet v 1, should be covalently linked to ViscoGel. However, the experiments performed within VIVAC do not provide a definitive POC for ViscoGel as adjuvant in SCIT. For that, treatment experiments have to be performed in an allergy model to investigate if the strong immune response elicited by Bet v 1-ViscoGel is able to counteract the pathological allergic immune response and ultimately lead to allergen tolerance.
Milestone 12: Preclinical characterisation and POC for therapeutic vaccination SLIT
The activities linked to Milestone 12 comprised both characterization and screening of candidate SLIT formulations and experiments dedicated to show preclinical POC for a candidate Bet v 1 SLIT vaccine formulation. They were performed by Partner 8, Stallergenes, in WP8.
Characterisation and screening to identify candidate SLIT formulations
In the first set of experiments ViscoGel particles (2 and 30 µm size) with covalently linked fluorescently labelled OVA (OVA-Alexa Fluor 488) were tested for in vivo uptake in cervical lymph node (LN) cells and for activation of cervical lymph node T-cells. ViscoGel particles with covalently linked OVA did not, irrespective of particle size, enhance the uptake of fluorescently labelled antigen by cervical LN cells 12 hours after sublingual administration. Similar to the Viscosan formulated OVA it resulted in less uptake compared to free OVA. The test formulations were then applied to an in vitro system assessing antigen capture by human monocyte derived dendritic cells (DC). In this system the OVA formulated in Viscosan generated similar uptake as the OVA-alone control, while the ViscoGel-formulations resulted in slightly less uptake after 0.5 and 1 hour.
None of the test formulations were able to significantly enhance the in vitro or in vivo uptake by antigen presenting cells or the activation of cervical LN T-cells, in contrast to a positive control (OVA-PSC, i.e. maltodextrin nanoparticle formulated OVA (Razafindratsita et al. 2013, JACI 120:278)). We concluded that covalently linked antigen is not advantageous in this system and set out to design a new set of formulations based on the first results.
Taken together, the screening experiments did not lead to the identification of an obvious SLIT candidate formulation. As there are no absolute experimental parameters defining formulations that will give a successful outcome in SLIT, it was decided to formulate rBet v 1 in 0.2% Viscosan for application in a SLIT model for birch pollen allergy.
Conclusion
The characterization of a number of different Viscosan and ViscoGel formulations with the model antigen OVA for antigen presenting cell (APC) capture in vitro and in vivo did not lead to the identification of any formulation able to significantly enhance the antigen uptake by APCs, a characteristic that is considered to be of importance for efficient immune stimulation. A slight effect on in vivo activation of cervical LN T-cells after sublingual administration of OVA formulated with 0.2% Viscosan or with LTX-315 was observed. We conclude that covalent linkage of the antigen to chitosan has a negative effect on the APC uptake and T-cell stimulation in sublingual antigen administration. Moreover, in the present experiments ViscoGel particles, either of larger size (mean 30 µm) or small size (mean 2 µm), did not have a positive effect on antigen capture by APCs or on T-cell activation. In the final SLIT POC study a tendency to a positive treatment effect was detected for Bet v 1 formulated in 0.2% Viscosan. Since the effect was not statistically significant, we could however not show preclinical POC for Viscosan as adjuvant in therapeutic vaccination.
Milestone 13: Protection of IPR developed in RTD activities
The activities linked to Milestone 13 were dedicated to the management of IPs emanating from VIVAC RTD activities and to ensure proper IPR protection of project results. These WP9 activities are described in the 'Potential impact, Dissemination and Exploitation' section below.
Milestone 14: Exploitation plan and plan for the use and dissemination of knowledge
An exploitation plan handling the VIVAC results has been prepared. It is briefly presented in the 'Potential impact, Dissemination and Exploitation' section below, together with a description on dissemination activities. Milestone 10 was linked to the tasks of WP10.
Overall Summary of S&T results/foregrounds
The VIVAC project has, with a few exceptions, been performed according to plan. The S&T project activities have led to new foregrounds that will form the basis for exploitation of IPs and generate further scientific development.
Key findings, new foregrounds
- Characterisation of Viscosan and ViscoGel: A thorough characterisation of Viscosan revealed important physicochemical properties. Method development provided means for analysing gel properties of ViscoGel and gel stability data were obtained. The data have been included in the regulatory documentation on Viscosan/ViscoGel.
- ViscoGel manufacturing: Process development resulting in a GMP manufacturing process. Having such a process in place is of critical importance for future drug product development and clinical testing.
- Formulation development: ViscoGel could be stably formulated with rBet v 1, nBet v 1 and LTX-315. rBet v 1 was also covalently linked to ViscoGel. A vaccine designed for clinical trial use as a bedside mix of ViscoGel and Act-Hib (Sanofi-Pasteur) that met all regulatory guidelines was successfully manufactured.
- Toxicity data obtained in mice and rabbits: Clean toxicity reports on ViscoGel and ViscoGel-Act-Hib was obtained after evaluation of local and/or systemic effects induced by three intramuscular administrations over a five week period, as well as recovery from any effects or potential delayed systemic toxic or local effects after a six week recovery period.
- Preclinical POC for ViscoGel as adjuvant: Preclinical POC for ViscoGel as adjuvant was obtained with the model vaccine Act-Hib (Sanofi-Pasteur). Data obtained on the innate and adaptive immune response induced by ViscoGel will be of importance for further development of ViscoGel based vaccines.
- POC data in man for ViscoGel as adjuvant: Safety and efficacy data from a Phase I/IIa trial was obtained for ViscoGel alone (safety) and as adjuvant for the model vaccine Act-Hib (safety and efficacy). Safety objectives were fully accomplished, while the primary efficacy objectives could not be fully addressed due to unexpectedly high variations in base-line anti-Hib antibody titers. In subgroup analyses where subjects with the highest base-line anti-Hib titers were excluded a positive effect of ViscoGel could be detected. The clinical trial results are of critical importance for the exploitation of ViscoGel as adjuvant for human vaccines.
Concluding remarks on S&T results
The VIVAC project has mainly been performed according to the plan. An amendment to the Description of Work (DoW) was approved in March 2012. The main change was an extension of the project until the end of December 2012. The extra four months added to the project time were needed to be able to include results from a clinical trial on ViscoGel in the final report. In addition, two new partners, KTA and PCG, joined VIVAC. KTA had been involved in VIVAC from the project start but not as an individual partner. PCG was engaged in the project to ensure that the clinical trial could be successfully performed within the given time frame.
The overall objective of VIVAC to develop and show POC for ViscoGel as a novel adjuvant was fulfilled for prophylactic vaccination, showing safety and efficacy as adjuvant in man. For therapeutic vaccination useful data have been obtained for the use of ViscoGel as adjuvant for Bet v 1 in SCIT application. The data obtained from SLIT formulations will support further development of ViscoGel for mucosal vaccination. The new foregrounds obtained from the VIVAC data are of critical importance for the further development and exploitation of ViscoGel as an adjuvant for human prophylactic and therapeutic vaccines. The project has led to new foregrounds and to potential new collaborations for the benefit of the participating SMEs. In VIVAC, ViscoGel was proven to constitute a simple, safe and versatile adjuvant system applicable for human use.
In a wider perspective, such an adjuvant system may provide solutions to current challenges in the development of therapeutic vaccines to e.g. cancer, autoimmune diseases and allergy, as well as for the development of vaccines to infectious diseases to which efficient protection cannot be provided with present vaccines.
Ethical considerations
When studying vaccines and adjuvants, examination of immune responses generated in vivo is necessary. Thus animal experiments were essential for the successful performance of VIVAC. Furthermore toxicity studies are compulsory for medical application products. When developing therapeutic vaccines, relevant disease models are needed. In VIVAC a mouse model for birch pollen allergy was developed. The animal experiments in VIVAC have been carried out according to the fundamental principle of the 3Rs (Replace, Reduce and Refine) for work with animals. Approvals for animal experiments were obtained from the local ethics committees for animal welfare in France, Spain, Sweden and UK.
Implementation of the 3Rs:
- Replacement: various in vitro methodologies used when possible, e.g. SLIT formulations were screened in human monocyte derived DC cultures.
- Refinement: mice anesthetized appropriately before sacrificing for collection of tissues; animal accommodations meeting the needs of the animals including nesting, 12-/12-hour light/dark cycle and with food and water ad libitum.
- Reduction: the number of animals kept to a minimum by use of inbred strains and standardized procedures for treatment and analysis.
The clinical trial was conducted in accordance with the ethical principles originating in the Declaration of Helsinki in its latest version (the 52nd WMA General Assembly, Edinburgh, Scotland, October 2000), and in consistence with GCP and applicable regulatory requirements.
Swedish laws (in compliance with the Declaration of Helsinki) were followed concerning the collection, storage and experimental use of human material and for electronic data confidentiality, security and integrity. All study subjects gave their informed consent to participate in the study.
Data and safety monitoring was conducted by a data safety monitoring board (DSMB). The trial protocol and amendments to the protocol, the Investigator's Brochure, the study subject information and informed consent form and subject recruitment procedures were evaluated and approved by the local Ethics Committee at Karolinska Institutet in Stockholm. Approval from the medical product agency was required and was obtained from the Swedish MPA.
Potential Impact:
Potential impact of project results
Despite the undisputable success of vaccines and vaccine programs in the battle against infectious diseases several challenges still remain. The unmet needs include both therapeutic vaccines to e.g. cancer, autoimmune diseases and allergy, and prophylactic vaccines to several infectious diseases. Examples of diseases to which efficient vaccines are still lacking include malaria, tuberculosis and HIV- infection/AIDS, collectively responsible for millions of deaths every year. A group of patients with a particular need for efficient vaccines is the worldwide growing elderly population. Individuals over the age of 65 often get insufficient protection from current vaccination to e.g. seasonal influenza and pneumococcal infections. Thus there is a need for vaccines able to elicit efficient and appropriate immune responses.
New vaccines developed today are often based on subunits that do not have a strong effect on the immune system. Moreover, in the situation of a pandemic, shortage of vaccine doses is an actual threat. In the case of therapeutic vaccination, modulation of an established pathological immune response is required. Depending on the indication, the vaccine has to break immune tolerance (cancer vaccines), induce self-tolerance (autoimmune diseases) or elicit appropriate non-pathogenic responses or tolerance (allergy). Thus safe and efficient adjuvants able to promote strong and appropriate immune responses are urgently needed.
Technology platforms for adjuvants fulfilling the requirements listed above have the potential to provide solutions to the unmet needs for novel prophylactic and therapeutic vaccines. This would influence health and quality of life for hundreds of millions of people worldwide, having a great socio-economic impact. Novel innovative adjuvant platforms also offer new opportunities for the vaccine market. Supporting such technology development at the European level will increase Europe's strength and competitiveness in this highly interesting and expanding market.
In VIVAC, the ViscoGel technology was proven to constitute a simple, safe, versatile and clinically applicable adjuvant system matching the requirements for a novel promising adjuvant platform. If successfully implemented the project results may thus contribute to:
- preventing shortage of vaccine supply, by reducing antigen needed per dose;
- improved protection against infectious diseases for which available vaccines have poor efficacy;
- development of therapeutic vaccines leading to improved quality of life, treatment and clinical outcome for patients with allergy or cancer;
- decreasing the societal costs in Europe and world-wide; and
- expand the vaccine/adjuvant market in Europe, leading to new opportunities for employment.
Impact for the participating SMEs
1) Viscogel AB (Partner 1): The successful development of ViscoGel as a medical product approved for clinical use, together with the positive outcome of the clinical trial will facilitate future applications of ViscoGel as adjuvant in human vaccines. In addition, through the preclinical studies performed within VIVAC, important information has been gathered on the mode of action for ViscoGel as adjuvant. This knowledge will promote further research and development on vaccine design. An exploitation plan has been set up for the use of ViscoGel, including a business model for the development of a commercial product(s).
2) Lytix Biopharma AS (Partner 2): Lytix Biopharma contributed to VIVAC with their background technology, a novel type of cationic peptides with cell-penetrating capacity. It was hypothesised that the cationic peptides could enhance the mucoadhesiveness of mucosal vaccine formulations. Furthermore, the cell-penetrating activity would increase the epithelial penetrating capacity of vaccine formulations intended for mucosal administration. In VIVAC the peptide LTX-315 was evaluated for the target application therapeutic allergy vaccination. LTX-315 has so far been applied in cancer treatment, since this type of peptides possesses strong anti tumour activity. In VIVAC LTX-315 was successfully formulated with ViscoGel and Viscosan (Viscogel's proprietary chitosan). Both LTX-315 alone and the ViscoGel/Viscosan formulated peptide were evaluated for potentially advantageous characteristics for application in sublingual allergy vaccination (SLIT). Although LTX-315 generated a slightly enhanced immune stimulation after sublingual delivery of a model allergen, this application of LTX-315 was not considered promising enough to pursue further development. Discussions were initiated between Lytix and Viscogel on other possible collaboration opportunities beyond VIVAC (subject not disclosed) and a dose-finding experiment for ViscoGel and LTX-315 was performed during the VIVAC project. Except for formulation development no new IP had been generated at the end of the project.
3) Inmunotek SL (Partner 3): Inmunotek is focused on the development and commercialization of innovative approaches to allergy diagnosis and treatment using non-recombinant (purified) and recombinant allergens. The key goal is to eliminate the drawbacks of conventional allergy treatment with unpurified natural extracts. In VIVAC Inmunotek's allergen technology was combined with Viscogel's adjuvant technology with the aim to develop new therapeutic allergy vaccines. Preclinical characterisation was performed on the immune response to both recombinant birch pollen allergen Bet v 1 and a purified birch pollen extract enriched for natural Bet v 1 in formulations with ViscoGel. It was found that ViscoGel might be a promising adjuvant candidate for use in subcutaneous allergy vaccination (SCIT). Further development is needed in order to obtain new IPRs in this area. VIVAC has generated scientific collaboration between Inmunotek and Karolinska Institutet (Partner 7) on allergen characterisation and between Inmunotek and Viscogel on a cancer vaccine project.
Dissemination of project results:
VIVAC project results were managed with the following objectives:
- to generate and protect new IPRs
- to present results at scientific conferences and in peer-reviewed journals
- to promote collaboration between VIVAC partners and to attract new collaborators and partners
- to support out-licensing of product candidates
Dissemination of results
All participants in VIVAC are entitled to publish project results after review by the VIVAC steering committee (SC, consisting of representatives for the three SMEs). The SC has the right to delay a publication for a reasonable time period in order to ensure appropriate action if the data to be presented could be the subject matter of intellectual property protection. The funding by the FP7 program 'Research for SMEs' has been, and will be, acknowledged in all publications and presentations of VIVAC results.
VIVAC results have so far been presented at the following vaccine/adjuvant-, allergy- and chitosan conferences:
- IMV (Modern Vaccines Adjuvants & Delivery Systems) in Porto, Portugal, April 6-8, 2011
- EAACI (European Academy of Allergy and Clinical Immunology) meeting in Istanbul, Turkey, June 11-15, 2011
- 4th International Conference on Drug Discovery & Therapy, Dubai, United Arab Emirates, 12-15 February 2012
- IAMV (Modern Vaccines Adjuvants & Delivery Systems), Copenhagen, Denmark, July 4-6, 2012
- 6th IberoAmerican Chitin Symposium / 12th International Conference on Chitin and Chitosan, 2-5 September, Fortaleza, Brazil
One report on VIVAC results has been published in a peer-reviewed journal:
- Neimert-Andersson T., et al. 'Improved immune responses in mice using the novel chitosan adjuvant ViscoGel, with a Haemophilus influenzae type b glycoconjugate vaccine' Vaccine, (2011) 29:8965-73
Additional publications will result from VIVAC. Publications of mechanism of action for ViscoGel as adjuvant and on clinical trial results are planned. Viscogel AB has published three press releases directly related to the VIVAC project.
Scientific /business collaboration
To support the collaboration between the VIVAC project partners three VIVAC project meetings have been organised:
- VIVAC Kick-off meeting in Stockholm, September 2-3, 2010
- VIVAC Half-time meeting, Istanbul, June 10-11, 2011
- VIVAC Final project meeting, Stockholm, April 16-17, 2012
Collaborations have been initiated between the SME partners, as described above. In addition Viscogel has together with Karolinska Institutet received a four years grant from the Swedish Research Council to a PhD student who will be funded during four years to investigate immune mechanisms of action for ViscoGel. These partners (KI and Viscogel) have also started collaboration on the development of allergy vaccines with ViscoGel. The VIVAC project consortium has provided a scientific/business network for potential future collaborations between project participants.
As a result of the presentations and publication of preclinical results on ViscoGel as an adjuvant, collaborative and business agreements have been established between Viscogel and vaccine companies, both within veterinary and human medicine.
IPR management
The IPR strategy to define pre-existing know-how, the establishment and protection of intellectual property (IP) and ensuring confidentiality of information shared in the VIVAC project have been critical activities to ensure a successful commercialization of the results.
The process for handling IPR in VIVAC was regulated by the grant agreement, stating that the ownership of the project results will remain with the SMEs and the RTD performers should be remunerated 100% for their work. During the VIVAC project the results have been carefully evaluated to make sure that novel IPR opportunities will be protected. No applications for novel intellectual property rights (patent applications, trademark rights etc.) have been filed during the VIVAC project. The results/foreground obtained in VIVAC will though constitute a valuable foundation from which new IPRs and out-licensing of products/technologies will be managed according to the business model of each SME.
Exploitation of results:
The target applications of the VIVAC project i.e. i) prophylactic vaccination against common infectious diseases, and ii) therapeutic allergy vaccination, both represent billion EUR markets. A successful outcome of the VIVAC project would significantly improve the competitive situation for the SME partners and create new commercialisation opportunities.
Market segments, vaccine market
Prophylactic vaccines
Expansion of the vaccine market is primarily driven by new innovations and increased market growth, which is in part driven by the focus on infectious diseases and the threat of pandemics from new types of influenza. The market has also proved willing to pay higher prices for more effective products. The rapid growth, approximately 30 percent per year during the period 2004-2007, can be compared with the figure of 8 percent annual growth for the pharmaceutical industry as a whole. CAGR during the period 2007-2017 is expected to be 11.5 percent. Vaccine sales during 2010 are estimated to USD 28 billion according to GBI Research. Following a number of structural deals, the vaccine market has come to be dominated by the major pharmaceutical companies (Big Pharma), which currently account for about 85 percent of the total vaccines market. Sales of vaccines in the veterinary market are estimated at USD 5.9 billion (GBI Research) with annual growth of about 1 percent.
A large part of successful development in the vaccine field has been through the development of more efficient adjuvants. ViscoGel's properties provide the potential for improved adjuvants that can be utilized for improved and entirely new vaccines for both human and veterinary medicine.
Therapeutic vaccines The market for therapeutic vaccines has great potential to add new treatment concepts in many indication areas, including allergies, nicotine addiction, autoimmune and cardiovascular diseases. A substantial number (hundreds) of products are under development and a few of them have reached the market like Provenge, a prostate cancer vaccine approved in the US and Oncophage, a kidney cancer vaccine approved in Russia.
The high incidence of allergic diseases has highlighted the need for efficient treatments, and the allergy vaccine area has been assessed as an interesting market. It is estimated that 10-30% of the population in the US and at least 20% in Europe suffers from allergic rhinitis. According to the World Allergy Organization report in 2008, approximately EUR14 billion are spent globally each year on allergic rhinitis and in 2007, the total incremental cost of asthma to society in the US was $56 billion (Barnett and Nurmagambetov, J Allergy Clin Immunol 2011). Birch pollen allergy affects approximately 20% of the population in exposed areas, e.g. in central and northern Europe (European Community Respiratory Health Survey, 2007).
Safety risks, long treatment time and complex dosages have prevented more widespread use of allergy vaccines. Most patients today exclusively receive symptomatic treatment. Medications in fact represent the largest cost component of direct medical expenditures for asthma and rhinitis. Thus it is of importance to weigh the costs for a lifelong consumption of drugs against the cost for allergy vaccination. Over longer time periods it has been shown that patients treated with SCIT or SLIT vaccination display a lower mean annual cost than patients who only receive symptomatic treatment. The anti-allergy drug market is anticipated to exceed 14.7 BUSD by 2015 in the US alone according to GIA. Worldwide allergy vaccine sales were 642 MUSD in 2010 and could be worth billions if new technologies succeed in achieving long-term relief of symptoms, significant cost advantages compared with medication and more convenient dosage as necessary for practical use. One can anticipate that allergy vaccines will prove cost-effective in the long run and could thus also improve the overall health economics.
Potential partners
The vaccine market is currently dominated by five large players, Merck&Co, Sanofi Pasteur, GlaxoSmithKline, Pfizer and Novartis. MedTrack databases list over 500 vaccine companies with vaccine candidates in development.
While Big Pharma dominates the market for vaccines to end customers, much of innovative technical development is performed by smaller biotechnology companies with which the major companies are interested in creating alliances. Examples of such alliances include the close collaboration between Intercell AG with both Novartis and GSK with regard to the IC-31 adjuvant and the collaboration between Sanofi and Crucell on new production methods for influenza vaccines. Big Pharma has an obvious interest in new market best-sellers and these have been achieved through acquisitions and alliances for specialized vaccines such as Prevnar (Pfizer), Gardasil (Sanofi Merck) and Cervarix (GSK).
Competitors
Several competing adjuvants are in the process of development, but only four adjuvants are currently found in approved vaccines globally. These are:
- Aluminiumhydroxid (alum) has been a standard for adjuvants since the beginning of the 1900s. A consensus exists in the industry that a need exists for improved adjuvants capable to induce cellular responses
- AS03 (GSK), which is based on squalene and used in Pandemrix for H1N1 vaccination. Not approved for use in the US.
- AS04 (GSK), which is based on aluminum hydroxide and monophosphoryl lipid A (MPL) and used in hepatitis and HPV vaccines.
- MF59 (Novartis), which is based on squalene and used in influenza vaccines. Not approved in the US.
The main competition of a novel therapeutic allergy vaccine is conventionally used therapeutic drugs targeting the allergy symptoms. The anti-allergy drug market is currently dominated by antihistamines, which represent the most widely prescribed anti-allergy products, followed by corticosteroids.
VIVAC business model
Exploitation strategy of results
The strategy is to market novel technologies to leading global companies in vaccines, pharmaceuticals and drug delivery. The business model builds on initially demonstrating Proof-of-Concept (PoC) for the selected application areas, that is, clear data to demonstrate that the technology works. Based on this data and the SME's intellectual property rights, potential partners are identified for further evaluation, development and commercialization. The partnerships are facilitated by license or collaboration agreements with a revenue model that includes upfront payments, milestones and royalties.
Profiling and searching for partner opportunities Potential partners are sought within the existing network as well as search databases (e.g. MedTrack, Thompson Pharma) to identify vaccine companies worldwide, with a potential need for novel technologies. Based on the ideal profile of a partner the search strategy is progressively refined. The search results are then segmented into indication areas, development phase, size etc. down to a limited target list of vaccine company contacts that will match the need of an ideal partner to SME.
Evaluation phase
Most likely the Due Diligence phase and business negotiations are preceded by an evaluation phase where the collaboration partner will test the adjuvant technology pre-clinically in combination with their own vaccine candidates, which are in development. These R&D collaborations may enhance the interest of the SME's technologies within the company and also enable identification of novel future product candidates and business opportunities. The evaluation phase will be implemented under Material Transfer Agreements (MTA) as well as R&D Collaboration Agreements. A successful outcome of the evaluation phase will add value to the SME and increase the chances of continued successful term sheet negotiations
Deal management
The final deal or deals can be structured in many ways depending on how to address different complex situations. The main types of structure will be licenses, acquisitions and joint ventures.
Alliance management making the deal work
The most likely outcome during the commercialization is license agreements where the SME's license the IPR related to the technology to a larger vaccine development company with financial capacities to continue the development into a marked product. The license agreement will not only be a plain license but rather a strategic alliance between the companies where the continued collaboration and effective development is of great importance. Successful alliance management is the key to ensure the continued development and commercialization of the new product based on the SME's technologies.
Exploitable results from VIVAC (New/Exploitable foreground; Description, Utilization)
1) Characterisation data on Viscosan and ViscoGel; Supporting the regulatory documentation on Viscosan/ViscoGel.
2) ViscoGel manufacturing; Process development resulting in a GMP manufacturing process.
3) Formulation development; New improved formulation processes and analyses. Data on ViscoGel formulation with Bet v 1, LTX-315, OVA and Act-Hib.
4) Toxicity data obtained in mice and rabbits; Supporting regulatory documentation for clinical use.
5) Preclinical POC for ViscoGel as adjuvant; Data obtained on the innate and adaptive immune response induced by ViscoGel will be of importance for further development of ViscoGel based vaccines.
6) POC data in man for ViscoGel as adjuvant; Exploitation of ViscoGel as adjuvant for human vaccines.
Concluding remarks on potential impact, dissemination and exploitation of results
There is a considerable global need for new vaccines that are able to induce efficient protection to infectious diseases. An adjuvant enhances the efficacy of the vaccine and lower the production cost through reduction in the quantity of antigen. In total only four adjuvants have been licensed in the EU and US. There is thus a significant opportunity for new adjuvants. Indeed, in later years the prospects for the global vaccine market have dramatically improved and significant growth potential is indicated. Vaccination strategies are also sought for therapeutic indications e.g. cancer and allergy, where the adjuvants' immunomodulatory capacity represents a significant exploitation possibility.
In VIVAC, the ViscoGel technology was proven to constitute a simple, safe, versatile and clinically applicable adjuvant system matching the requirements for a novel promising adjuvant platform. Such a platform provides means to increase the efficacy and duration of a vaccine. In addition it will potentially reduce the costs for manufacturers and payers, and improve the supply in a pandemic, which is of interest to governments and global health organizations.
Several new foregrounds were obtained during the VIVAC project, supporting the development of ViscoGel as an adjuvant for prophylactic and therapeutic vaccines. The positive results from the Phase I/II clinical trial for ViscoGel as adjuvant in man have paved the way for new partnering agreements with vaccine companies. Valuable scientific collaborations and potential new partner contacts have been generated for the participating SMEs. The novel results/foregrounds will constitute an important foundation from which new IPRs and out-licensing of products/technologies will be managed.
In conclusion, the VIVAC project has significantly improved the competitive situation for the SME partners and created new commercialisation opportunities. On a societal level, the development of an adjuvant technology applicable in novel prophylactic and therapeutic vaccines will have a potential impact on health and quality of life, as well as a beneficial effect on health economics.
Project website: http://www.vivac.se
Safe and efficient prophylactic vaccines are still lacking for a number of infectious diseases. Moreover therapeutic vaccines to e.g. cancer, autoimmune diseases or allergy, constitute an emerging area of interest. The effect of a vaccine can be enhanced by adjuvants, which are also able to direct the type of immune response elicited. Thus novel adjuvants have the potential to improve prophylactic and therapeutic vaccines.
In the VIVAC project the overall objective was to develop and to show safety and efficacy for a new innovative carbohydrate (chitosan) based adjuvant - ViscoGel - to be used both in prophylactic and therapeutic vaccination. For prophylactic vaccination a model vaccine to Heamophilus influenzae type b (causing bacterial meningitis), Act-Hib, was used to show preclinical and clinical proof of concept (POC).
For therapeutic vaccination the target was allergy vaccination using the major birch pollen allergen Bet v1. In addition an immune- and permeation- enhancing peptide, LTX-315, was evaluated, since mucosal allergy vaccination through the sublingual route was specifically addressed. Three SMEs (Viscogel AB, SE; Lytix Biopharma AS, NO; Inmunotek SL, ES) provided their background technologies to the project: ViscoGel manufacturing, LTX-315 and recombinant as well as natural purified Bet v 1.
Research and technical development (RTD) activities were performed to reach the project goals. Extensive formulation work was carried out including design, development and characterization of chitosan and ViscoGel formulations. A number of activities focused on the development of a clinical ViscoGel product for prophylactic vaccination. Preclinical characterization of ViscoGel-Act-Hib led to the identification of a ViscoGel clinical product candidate that was subjected to extensive characterization, process development and GMP production. Toxicity evaluation of ViscoGel and ViscoGel-Act-Hib was carried out in two species. The compiled preclinical documentation on ViscoGel formed the basis for regulatory and ethical approval to perform a clinical Phase I/IIa trial to show POC for prophylactic vaccination.
The clinical trial evaluated safety and efficacy of one intramuscular injection of ViscoGel alone and as adjuvant for Act-Hib. RTD on ViscoGel formulations for allergy vaccination followed two lines, development of vaccines for subcutaneous (SCIT) and for sublingual (SLIT) allergen specific immunotherapy/vaccination. The target was birch pollen allergy and the major allergen Bet v 1. Mouse experiments were performed to find promising Bet v 1 SCIT candidates formulated with ViscoGel. A mouse model for birch pollen allergy and SLIT was established to obtain preclinical POC for ViscoGel as an adjuvant in SLIT. Experiments to identify SLIT candidates were performed with a model antigen, OVA, evaluating formulations containing OVA in chitosan solutions, with ViscoGel and with LTX-315. Finally a Bet v 1 SLIT candidate was tested in the SLIT model.
The most important result of VIVAC was the development of a clinical ViscoGel adjuvant product that was applied in a Phase I/IIa trial. Intramuscularly administered ViscoGel was shown to be safe and well tolerated in man. Subgroup efficacy analyses revealed a positive adjuvant effect of ViscoGel. These results are of critical importance for the exploitation of ViscoGel as adjuvant in human vaccines. For therapeutic vaccination useful data were obtained on formulation of ViscoGel based allergy vaccines intended both for SCIT and for mucosal vaccination, which will support further developmental work.
In conclusion, VIVAC has provided an innovative platform for development of ViscoGel as adjuvant in prophylactic and therapeutic vaccines. The project has generated new foreground and potential new collaborations for the benefit of the participating SMEs. In VIVAC, ViscoGel was proven to constitute a simple, safe and versatile adjuvant system applicable for human use. In a wider perspective, such an adjuvant system may provide solutions to current challenges in the development of therapeutic vaccines to e.g. cancer, autoimmune diseases and allergy, as well as for the development of vaccines to infectious diseases to which efficient protection cannot be provided with present vaccines.
Project Context and Objectives:
There is a huge global demand for new vaccines able to elicit efficient and appropriate immune responses to infectious agents (prophylactic vaccines) as well as vaccines capable to modify pathogenic immune responses (therapeutic vaccines). Suboptimal vaccines may be improved by adjuvants, i.e. enhancers of the immune response. Adjuvants also provide means to modify an immune response and direct it towards a specific functional response. The route of administration is known to affect the immune response stimulated and, in addition, adjuvants can be designed to act as vehicles or delivery systems for vaccine administration, e.g. for mucosal vaccines. Only four adjuvants in total have been licensed in the EU and US. There is therefore a significant opportunity for new adjuvants and vaccine technologies, as vaccine design has focused on highly purified antigens with limited efficacy.
In the VIVAC project the overall objective was to develop and to show safety and efficacy for a new innovative carbohydrate (chitosan) based adjuvant - ViscoGel - to be used both in prophylactic and therapeutic vaccination.
Specific objectives set up for VIVAC:
1) to develop analytic tools for quality assessment of ViscoGel preparations and provide building blocks for formulations;
2) to characterize and optimize chitosan gel systems with controllable biodegradation and mucoadhesive properties;
3) to provide GMP-produced ViscoGel formulated with Act-Hib for clinical application;
4) to investigate the nature of the immune response to antigens administered with ViscoGel and if the co-formulation with LTX-315 can enhance the adjuvant and epithelial penetrating capacity
5) to provide formulations of ViscoGel with Bet v 1, with LTX-315 and with both Bet v 1 and LTX-315 intended for preclinical application;
6) to show POC for prophylactic vaccination using ViscoGel formulated with Hib and to demonstrate preclinical and clinical safety;
7) to show POC for therapeutic vaccination using ViscoGel formulated with Bet v 1 in relevant preclinical sub-lingual immunotherapy (SLIT) and subcutaneous immunotherapy (SCIT) models for treatment of birch pollen allergy;
8) to develop new and increased IP protection for candidate ViscoGel formulations; and
9) to obtain the documentation needed for clinical development and commercialisation.
Three SMEs participated in the VIVAC project and contributed with their expert competences:
1) Viscogel AB, Sweden, provider of the ViscoGel technology;
2) Lytix Biopharma AS, Norway, provider of peptide technology and LTX-315; and
3) Inmunotek SL, Spain, provider of Bet v 1.
To achieve the VIVAC project goals, the following activities have been performed:
1) Development and production of ViscoGel formulations, including development of a ViscoGel manufacturing process according to GMP.
2) Characterisation of chitosan and gels; assessment of physicochemical, mucoadhesion and permeation properties.
3) Preclinical characterisation and POC of ViscoGel as adjuvant for prophylactic vaccination to Hib.
4) Toxicology evaluation and clinical trial to obtain safety data and show POC for ViscoGel in man.
5) In vitro and in vivo characterization of ViscoGel preparations for SLIT application, establishment of a mouse model for sensitization to birch pollen allergen, and evaluation of candidate vaccines.
6) In vivo characterization of ViscoGel preparations with recombinant and natural Bet v 1 for SCIT application.
7) Management and dissemination of project results.
Project Results:
Introduction
The overall objective of VIVAC was to develop and show proof of concept (POC) for ViscoGel as a novel adjuvant for prophylactic and therapeutic vaccination. An overview of the results of VIVAC shows that the objective has been fulfilled for prophylactic vaccination, showing safety and efficacy for ViscoGel as adjuvant in man. For therapeutic vaccination useful data have been obtained for the use of ViscoGel as adjuvant, but POC was not obtained for this application. The project results will here be presented as reports of the individual milestones set up for VIVAC, followed by a summary description of the main S&T results/foregrounds of the project.
Milestone 1: Recombinant and natural Bet v 1 for formulation with ViscoGel
The objective of Milestone 1 was to provide recombinant and natural Bet v 1 for formulation with ViscoGel early in the project. One hundred mg of recombinant (r)Bet v 1 and 200 mg of natural (n)Bet v 1 were delivered on time from Partner 3, Inmunotek SL, to Partner 1, Viscogel AB. It was important to show that both the rBet v 1 and the nBet v 1 purified from birch pollen extract were of high quality and, most importantly, that they possessed retained allergenicity. This was shown by analysis of binding to patients' IgE.
Milestone 2: LTX peptide for formulation with ViscoGel
LTX-315 was synthesised by Bachem AG, Bubendorf, Switzerland, on commission of Partner 2, Lytix Biopharma AS. One gram of the synthetic LTX-315 peptide, LTX-315 Acetate batch 1015058, was delivered on time to Partner 3, Viscogel AB, together with a declaration on physico-chemical characteristics of the product.
The objective of Milestone 2 was to provide LTX-315 to the project. This was also the objective of WP2, with Partner 2, Lytix Biopharma, as lead beneficiary.
Milestone 3: ViscoGel formulations with Hib, Bet v 1 and LTX-315 for preclinical applications
Milestone 3 served as a checkpoint for providing formulations for prophylactic and therapeutic vaccine design and preclinical testing. The development and production of chitosan, Viscosan and ViscoGel preparations with different properties was carried out by Partner 3, Viscogel, from the start of the project and continued after the delivery date of Milestone 3 at month 9.
ViscoGel formulated with rBet v 1 and nBet v 1 was produced together with control test material and was delivered to Partner 3, Inmunotek, for application in mouse SCIT experiments (WP8). For the last experiment rBet v 1 was also covalently linked to ViscoGel in order to assess if physical linkage between antigen and ViscoGel enhanced, or possibly modified, the immune response induced.
Based on the results from the evaluation of these formulations using OVA, a candidate Bet v 1 vaccine was designed, where rBet v 1 was formulated by mixing the allergen in a Viscosan solution. Results of screening experiments for SLIT, as well as the POC-experiment in the Bet v 1 SLIT model are described below in the Milestone 12 report.
Milestone 4: Description of chitosan and gel properties, as well as stability and antigen release data
The major results of WP4 are given here as a report on Milestone 4. The aim of this milestone was to investigate the suitability of ViscoGel as a vehicle for antigens in vaccine design. The method development and results obtained in WP4 were of importance for compiling an Investigational medical product dossier (IMPD) for Viscosan/ViscoGel. Partner 4, NTNU, was the lead beneficiary in WP4.
Overall conclusions
Characterisation of Viscosans has successfully been carried out applying proton NMR spectroscopy, intrinsic viscosity measurements and SEC-MALLS. Even though the characterisation of ViscoGel systems, both in terms of bulk properties and particulate gel stability, was found to be unexpectedly challenging, the methods used for their characterization in this report seem to provide the necessary information.
The results obtained in this WP regarding the Viscogel properties confirm the appropriateness of ViscoGel as an administration form for the presentation of antigens. The gels are very stable under sterile conditions suggesting that antigen-containing products can be manufactured and stored for a prolonged period of time. Furthermore, the obtained results also suggest that ViscoGels can be tailored to meet specific demands with respect to biodegradability and hence also specific antigen properties.
Milestone 5: Characterisation of Viscogel-formulation for SLIT
This Milestone was dedicated to studies on mucoadhesion and permeability characteristics of Viscosan and ViscoGel preparations. The aim was to gain information that could guide the design of allergen-ViscoGel/Viscosan formulations for SLIT application. The activities linked to Milestone 5 were performed by Partner 5, Hacettepe.
Mucoadhesion
The mucoadhesion studies were performed on bovine buccal tissue freshly obtained from the slaughterhouse. The epithelial tissue was separated from the connective tissue. Mucoadhesion was assessed with a Texture Analyser using a mucoadhesive rig. The force needed to detach the test formulations was recorded as a function of elongation and both maximum strength and area under the force/time curve was obtained. The results were converted into work of adhesion (mJ).
The adhesion was found to be significantly increased with increased contact time. Increasing the contact time provides interdiffusion and chain entanglement between polymer and mucin chain in mucus membrane. Extending the contact time between mucoadhesive polymer and mucosa causes secondary bond formation, increasing the mucoadhesive strength.
Mucoadhesion was found to be affected by the viscosity of the test preparations, showing a positive correlation between viscosity and mucoadhesion (i.e. increased viscosity corresponded to increased mucoadhesion.
Evaluation of the mucoadhesion of Viscosan with different viscosity, DD and concentrations, with or without ViscoGel particles, revealed that only the viscosity had a significant impact on mucoadhesion. The presence of TEO or OVA affected the mucoadhesive properties, indicating that the physicochemical properties of a formulated compound, such as solubility, molecular weight etc., have to be taken into account when evaluating mucoadhesion of a Viscosan/ViscoGel formulation.
Mucosal permeability
Freshly obtained bovine buccal mucosa from the local slaughterhouse was used as a model for the non-keratinized human buccal mucosa. The underlying tissue was removed from the mucosa, and then the epithelium was separated from most of the connective tissue with the help of scalpel.
An effect was detected for viscosity (increased permeation with decreased viscosity), DD (decreased permeation with decreasing DD) and presence of ViscoGel particles (lower permeation for Viscosan with ViscoGel particles, compared to without particles), while concentration had no effect on permeation. With the commercially available chitosans, lower permeation was obtained compared to that of the Viscosans. The permeation profiles obtained for OVA was affected by DD (increased permeation with increasing DD), whereas no significant effect was obtained with viscosity and concentration. Presence of ViscoGel particles in the chitosan preparation was found to increase the permeation of OVA.
The permeability coefficients were calculated from the steady state of the permeation curves and comparison of the permeability coefficients of TEO and OVA revealed that permeability of TEO formulations was higher than that of OVA formulations. Higher permeability coefficients were obtained with high viscosity samples.
Permeability studies of different chitosan and viscosan preparations, with and without ViscoGel particles, formulated with the small drug theophylline (TEO) or the high molecular weight OVA revealed different patterns for the two model compounds. Generally permeation was lower for OVA than for TEO.
General conclusion
The mucoadhesion and permeation studies were performed with chitosan solutions with different physicochemical characteristics. Viscosity was the only property that affected mucoadhesion, but viscosity had opposite effects on permeation of TEO and no effect on permeation of OVA. It was found that incorporation of drug into chitosan preparations (model compounds TEO or OVA) affects mucoadhesion and permeation. Model compounds with similar characteristics to a test compound (e.g. protein nature, MW) could potentially generate useful data in this kind of studies, but the actual compound to be tested has to be evaluated. In VIVAC the mucoadhesion and permeation studies were meant to be performed for guidance of formulation design for SLIT studies with Bet v 1. Due to initial difficulties to apply the chitosan formulations in the mucoadhesion- and permeation assay systems and the demand for huge amounts of test substances, it was not feasible to perform these experiments with Bet v 1 within the given time frame. Thus the results obtained in WP5 could not be used for guidance when designing SLIT formulations for WP8.
Milestone 6: Preclinical characterisation and POC for prophylactic vaccination (ViscoGel-Hib)
The objective of Milestone 6 was to conclude the preclinical characterisation of ViscoGel as an adjuvant for prophylactic vaccination. Moreover preclinical data were obtained in mice to guide the selection of ViscoGel formulation for the clinical POC study. In the clinical trial of ViscoGel as adjuvant a model vaccine to Haemophilus influenzae type b, Act-HIB, was planned to be used and thus most preclinical evaluations were performed with Act-Hib. The results also formed the basis for the documentation in order to obtain all regulatory permissions to ensure that the clinical trials could be conducted. Here the results leading to selection of the formulation to be used in the clinical trial are briefly described.
A report has been published based on the studies related to Milestone 6 (Neimert-Andersson et al. (2011) Vaccine 29:8965). The activities were linked to WP7 and Karolinska Institutet was the lead beneficiary. The next aim was to characterize the immune response to Act-Hib when administered to mice together with ViscoGel via the subcutaneous (s.c.) or the intramuscular (i.m.) route, with the focus to provide data for the selection of ViscoGel formulation for the clinical POC study.
The local immune response to ViscoGel was investigated. When characterizing a novel adjuvant, it is of interest to compare it to a well-known adjuvant. The most widely used adjuvant is aluminium salts (alum). Alum is used both in experimental settings and until recently it was the only adjuvant approved for human vaccines. Therefore ViscoGel was compared to alum. Results indicate ViscoGel to be a superior immunostimulant compared to alum.
Conclusion
From the preclinical studies performed in WP7, we can conclude that ViscoGel is a potent adjuvant, superior to the established adjuvant alum, resulting in enhanced humoral and cellular responses when administered both subcutaneously and intramuscularly. The best effect was obtained with larger ViscoGel particles (200 µm) used together with Act-HIB. The 200 µm particles were used to characterize the cellular infiltration when administered both subcutaneously and intramuscularly. The results indicate that the primary action taking place locally is the rapid infiltration of granulocytes (neutrophils and eosinophils), which then can induce rapid, within three weeks complete, degradation of ViscoGel. The recruited neutrophils may interact with dendritic cells for priming of the adaptive branch of the immune system, resulting in a strong immune response.
A report presenting preclinical POC for ViscoGel as adjuvant for Act-Hib has been published:
Neimert-Andersson T., et al. 'Improved immune responses in mice using the novel chitosan adjuvant ViscoGel, with a Haemophilus influenzae type b glycoconjugate vaccine' Vaccine, (2011) 29:8965-73
Milestone 7: ViscoGel-Hib of GMP grade for clinical use
Based on the preclinical characterisation of ViscoGel as an adjuvant for the model vaccine Act-Hib, a ViscoGel to be formulated with Act-Hib was GMP produced for the clinical trial. A summary of the GMP production of ViscoGel, as well as a description of the ready to use kit with Act-Hib for the clinical trial is given here. Partner 1, Viscogel, was responsible for these WP3 activities.
GMP-produced ViscoGel
The entire process, spanning from manufacturing of chitosan (Viscosan) to release of a final test article for clinical use involved many steps, the most important being:
a) Establishment of product specifications for raw materials and products.
b) Implementation of a quality system for manufacturing of Viscosan (GMP compliant).
c) Manufacturing of Viscosan (50% DD).
d) Technology transfer and manufacturing of ViscoGel and ViscoGel particles at a GMP-approved Contract manufacturing Organisation (CMO).
e) Selection of packing materials and labelling.
f) Release of test material for clinical study.
g) Regulatory approval for clinical plan from the Swedish Medical Product agency (MPA) and from the local ethical committee.
In brief, early and very basic observations made us focus on the manufacturing of chitosan with a DD of 50%. Based on a large amount of experimental work, protocols for an efficient removal of endotoxins and protein impurities were identified. These results and information in European Pharmacopeia was the basis for setting limits for impurities in Viscosan and lead to a tentative product specification for Viscosan. The next step was to establish a quality system for the manufacturing of a starting material for the pharmaceutical industry that could meet the industrial standards. In brief, we implemented a GMP-compliant quality system for our manufacturing of Viscosan. A chemical process could then be developed for Viscosan, which meets the common goals normally used for industrial processes, i.e. a process that gives a consistent batch quality, has a low cost of goods (COGS), is scalable and that produces waste streams of low toxicity and a low environmental impact. Manufacturing of approved Viscosan batches for toxicology-, stability and clinical studies went according to plan and these Viscosan batches all met the targets set.
ViscoGel-Hib for clinical use
The product for the clinical trial consisted of ViscoGel in combination with the commercial vaccine, Act-Hib from Sanofi Pasteur MSD. The vaccine was designed to be intramuscularly injected after a bedside mixing procedure in which the vaccine, dissolved in a buffer, was added to a sterile ampoule of ViscoGel particles suspended in Ringers acetate.
APL delivered one type of ViscoGel vial in a kit containing up to three buffer vials and one vial of lyophilized Act-Hib. This kit was specially designed to enable the clinical personnel to mix these vials in to one of eight different formulations through a randomization procedure. The final formulation is a 'bedside preparation' that is prepared just before injection. Eight different kits were prepared in advance for the eight groups planned to be included in the clinical trial (clinical trial design described in Milestone 9). Careful measures were taken to assure exact and reproducible handling by the clinical trial personnel, in order to keep the doses exact and to avoid adherence to the walls of the glass vial.
Conclusion
A fully GMP compliant batch of ViscoGel was produced and a patient kit including all necessary vials packaged and delivered to the clinical trial unit on April 5, 2012.
Milestone 8: Toxicology study completed, toxicology evaluation report
The toxicity of ViscoGel, as well as for the formulated vaccine consisting of Act-HIB mixed with ViscoGel, was evaluated in mice and rabbits. Local and systemic toxic effects were carefully investigated after three intramuscular administrations of ViscoGel. A full toxicology report was filed by Partner 6, Huntingdon.
Conclusion
It is concluded that the three intramuscular injections of either ViscoGel or ViscoGel/Act-Hib vaccine, when compared to controls, did not elicit any systemic toxic effects. Treatment related changes were largely confined to the dose sites, with histopathological changes in the spleen and popliteal lymph nodes indicative of immunogenic stimulation. These findings indicated the presence of a local reaction at the injection sites and immunogenic stimulation, as expected from the pharmacological activity of the test articles, and not toxicity. Act-Hib vaccine take was confirmed by a positive antibody response but there was no CMI response.
The results of the toxicity studies performed in mice and rabbits did not reveal any systemic toxic effects caused by ViscoGel. The local reactions observed were linked to the immune stimulation induced by vaccination. An eight times higher dose than the start dose planned to be used in the clinical trial was considered to be safe in rabbits. The toxicity reports supported the application to the Swedish MPA and local ethics committee for permission to perform a clinical trial with ViscoGel and the ViscoGel/Act-Hib vaccine.
Milestone 9: POC in man for ViscoGel as adjuvant (for Hib), clinical trial result
Milestone 9 is dedicated to a Phase I/II POC clinical trial performed at a single centre, Karolinska Clinical Trial Alliance (KTA), Partner 9. The primary study outcome was safety of ViscoGel and secondary the adjuvant effect of ViscoGel mixed with Act-Hib for intramuscular vaccination was evaluated. The study was monitored and data processed and recorded by Partner 10, Pharma consulting Group (PCG).
Conclusion
The clinical trial performed in VIVAC has provided 'first in man' data on ViscoGel. Safety objectives were fully accomplished, while efficacy objectives could not be fully addressed due to unexpectedly high incidence of HIB exposure in the study population, leading to high base-line anti HIB antibody titers. However, subgroup analyses excluding subjects with the highest baseline anti-HIB titers (either the top half or top quartile) indicated a higher increase of anti-HIB antibody production in groups treated with ViscoGel. Importantly, preliminary data on the cellular response induced by ViscoGel point to a Th1-biased cell mediated response to Act-HIB with ViscoGel, while vaccination with Act-HIB alone seems to have an opposite effect on the cell-mediated response. The safety data and the positive data on efficacy provide a platform for further development of ViscoGel as an adjuvant for parenteral administration of human vaccines.
Milestone 10: Bet v 1-formulations in ViscoGel w and w/o LTX-315 for sublingual (SLIT) and subcutaneous (SCIT) allergen specific immunotherapy
The objective of Milestone 10 was to provide therapeutic Bet v 1 vaccine test formulations for preclinical characterisation and SLIT and SCIT POC studies. The formulations were provided by Partner 1, Viscogel, for activities in WP8 to be carried out by Partner 3, Inmunotek (SCIT), and Partner 8, Stallergenes (SLIT).
Test formulations for SCIT application
An initial experiment was performed at Viscogel (Partner 1) where ViscoGel formulations with covalently linked or mixed rBet v 1 were stored at +4oC for up to three weeks and then used for immunisation of mice. The immune response was compared to the response to rBet v 1 alone and to freshly prepared rBet v 1-ViscoGel. It was demonstrated that the rBet v 1-ViscoGel formulations were stable in terms of antigenicity when stored at +4°C for three weeks, irrespective to if rBet v 1 was coupled to or mixed with ViscoGel. Formulations for experiments aiming at characterising the immune response to subcutaneously administered rBet v 1 and nBet v 1 were then designed and produced. For the first experiments rBet v 1 and nBet v 1 (Bet v 1 enriched birch pollen extract fraction) were formulated with ViscoGel. For the last experiment rBet v 1 was also covalently linked to ViscoGel.
Test formulations for SLIT application
A main objective of VIVAC was to develop a ViscoGel-based allergy vaccine for SLIT with rBet v 1 and birch pollen allergy as target. The immunological mechanisms for successful SLIT are only partially understood and therefore the only way to confirm a functional SLIT vaccine formulation is to test it in an allergy model, where the candidate SLIT formulation is administered sublingually to sensitised mice.
However, allergy models and SLIT protocol are time- and resource demanding experiments. Therefore pre-screening of SLIT candidate formulations have to be done, identifying formulations with characteristics considered to be essential for a successful candidate.
The screening experiments were for technical reasons performed with the model antigen OVA instead of Bet v 1. Two sets of formulations were prepared. For the antigen uptake assays the formulations were prepared with fluorescently labelled OVA (OVA-Alexa Fluor 488) and for the T-cell activation studies the corresponding formulations were prepared with OVA. After evaluation of the screening experiments (see Milestone 12 below), a formulation of rBet v 1 in 0.2% Viscosan (50%DD) was prepared for a SLIT POC experiment in a mouse SLIT model.
Milestone 11: Preclinical POC for SCIT vaccination
The aim of Milestone 11 was to obtain data to support application of ViscoGel as adjuvant in SCIT with rBet v 1 and/or nBet v 1. The experiments focused on characterisation of the humoral and cellular immune response to parenterally administered Bet v 1 formulated with various ViscoGel preparations in order to find an optimal ViscoGel formulation for SCIT application. The activities were performed within WP8 by Partner 3, Inmunotek.
In conclusion, the immunisation with rBet v 1 and nBet v 1 showed that the immune response to both the recombinant Bet v 1 and the natural enriched allergen was enhanced by formulation with ViscoGel. Furthermore some interesting observations were made on subtle differences between the immune response generated by different administration routes (i.p. or s.c.) between responses to nBet v 1 and rBet v 1 and there were indications of a more Th1-skewed response generated by ViscoGel- than by alum-adjuvanted antigen. Taken together, the results support application of ViscoGel as a promising adjuvant for SCIT.
The data suggest that the allergen, which could be rBet v 1 or nBet v 1, should be covalently linked to ViscoGel. However, the experiments performed within VIVAC do not provide a definitive POC for ViscoGel as adjuvant in SCIT. For that, treatment experiments have to be performed in an allergy model to investigate if the strong immune response elicited by Bet v 1-ViscoGel is able to counteract the pathological allergic immune response and ultimately lead to allergen tolerance.
Milestone 12: Preclinical characterisation and POC for therapeutic vaccination SLIT
The activities linked to Milestone 12 comprised both characterization and screening of candidate SLIT formulations and experiments dedicated to show preclinical POC for a candidate Bet v 1 SLIT vaccine formulation. They were performed by Partner 8, Stallergenes, in WP8.
Characterisation and screening to identify candidate SLIT formulations
In the first set of experiments ViscoGel particles (2 and 30 µm size) with covalently linked fluorescently labelled OVA (OVA-Alexa Fluor 488) were tested for in vivo uptake in cervical lymph node (LN) cells and for activation of cervical lymph node T-cells. ViscoGel particles with covalently linked OVA did not, irrespective of particle size, enhance the uptake of fluorescently labelled antigen by cervical LN cells 12 hours after sublingual administration. Similar to the Viscosan formulated OVA it resulted in less uptake compared to free OVA. The test formulations were then applied to an in vitro system assessing antigen capture by human monocyte derived dendritic cells (DC). In this system the OVA formulated in Viscosan generated similar uptake as the OVA-alone control, while the ViscoGel-formulations resulted in slightly less uptake after 0.5 and 1 hour.
None of the test formulations were able to significantly enhance the in vitro or in vivo uptake by antigen presenting cells or the activation of cervical LN T-cells, in contrast to a positive control (OVA-PSC, i.e. maltodextrin nanoparticle formulated OVA (Razafindratsita et al. 2013, JACI 120:278)). We concluded that covalently linked antigen is not advantageous in this system and set out to design a new set of formulations based on the first results.
Taken together, the screening experiments did not lead to the identification of an obvious SLIT candidate formulation. As there are no absolute experimental parameters defining formulations that will give a successful outcome in SLIT, it was decided to formulate rBet v 1 in 0.2% Viscosan for application in a SLIT model for birch pollen allergy.
Conclusion
The characterization of a number of different Viscosan and ViscoGel formulations with the model antigen OVA for antigen presenting cell (APC) capture in vitro and in vivo did not lead to the identification of any formulation able to significantly enhance the antigen uptake by APCs, a characteristic that is considered to be of importance for efficient immune stimulation. A slight effect on in vivo activation of cervical LN T-cells after sublingual administration of OVA formulated with 0.2% Viscosan or with LTX-315 was observed. We conclude that covalent linkage of the antigen to chitosan has a negative effect on the APC uptake and T-cell stimulation in sublingual antigen administration. Moreover, in the present experiments ViscoGel particles, either of larger size (mean 30 µm) or small size (mean 2 µm), did not have a positive effect on antigen capture by APCs or on T-cell activation. In the final SLIT POC study a tendency to a positive treatment effect was detected for Bet v 1 formulated in 0.2% Viscosan. Since the effect was not statistically significant, we could however not show preclinical POC for Viscosan as adjuvant in therapeutic vaccination.
Milestone 13: Protection of IPR developed in RTD activities
The activities linked to Milestone 13 were dedicated to the management of IPs emanating from VIVAC RTD activities and to ensure proper IPR protection of project results. These WP9 activities are described in the 'Potential impact, Dissemination and Exploitation' section below.
Milestone 14: Exploitation plan and plan for the use and dissemination of knowledge
An exploitation plan handling the VIVAC results has been prepared. It is briefly presented in the 'Potential impact, Dissemination and Exploitation' section below, together with a description on dissemination activities. Milestone 10 was linked to the tasks of WP10.
Overall Summary of S&T results/foregrounds
The VIVAC project has, with a few exceptions, been performed according to plan. The S&T project activities have led to new foregrounds that will form the basis for exploitation of IPs and generate further scientific development.
Key findings, new foregrounds
- Characterisation of Viscosan and ViscoGel: A thorough characterisation of Viscosan revealed important physicochemical properties. Method development provided means for analysing gel properties of ViscoGel and gel stability data were obtained. The data have been included in the regulatory documentation on Viscosan/ViscoGel.
- ViscoGel manufacturing: Process development resulting in a GMP manufacturing process. Having such a process in place is of critical importance for future drug product development and clinical testing.
- Formulation development: ViscoGel could be stably formulated with rBet v 1, nBet v 1 and LTX-315. rBet v 1 was also covalently linked to ViscoGel. A vaccine designed for clinical trial use as a bedside mix of ViscoGel and Act-Hib (Sanofi-Pasteur) that met all regulatory guidelines was successfully manufactured.
- Toxicity data obtained in mice and rabbits: Clean toxicity reports on ViscoGel and ViscoGel-Act-Hib was obtained after evaluation of local and/or systemic effects induced by three intramuscular administrations over a five week period, as well as recovery from any effects or potential delayed systemic toxic or local effects after a six week recovery period.
- Preclinical POC for ViscoGel as adjuvant: Preclinical POC for ViscoGel as adjuvant was obtained with the model vaccine Act-Hib (Sanofi-Pasteur). Data obtained on the innate and adaptive immune response induced by ViscoGel will be of importance for further development of ViscoGel based vaccines.
- POC data in man for ViscoGel as adjuvant: Safety and efficacy data from a Phase I/IIa trial was obtained for ViscoGel alone (safety) and as adjuvant for the model vaccine Act-Hib (safety and efficacy). Safety objectives were fully accomplished, while the primary efficacy objectives could not be fully addressed due to unexpectedly high variations in base-line anti-Hib antibody titers. In subgroup analyses where subjects with the highest base-line anti-Hib titers were excluded a positive effect of ViscoGel could be detected. The clinical trial results are of critical importance for the exploitation of ViscoGel as adjuvant for human vaccines.
Concluding remarks on S&T results
The VIVAC project has mainly been performed according to the plan. An amendment to the Description of Work (DoW) was approved in March 2012. The main change was an extension of the project until the end of December 2012. The extra four months added to the project time were needed to be able to include results from a clinical trial on ViscoGel in the final report. In addition, two new partners, KTA and PCG, joined VIVAC. KTA had been involved in VIVAC from the project start but not as an individual partner. PCG was engaged in the project to ensure that the clinical trial could be successfully performed within the given time frame.
The overall objective of VIVAC to develop and show POC for ViscoGel as a novel adjuvant was fulfilled for prophylactic vaccination, showing safety and efficacy as adjuvant in man. For therapeutic vaccination useful data have been obtained for the use of ViscoGel as adjuvant for Bet v 1 in SCIT application. The data obtained from SLIT formulations will support further development of ViscoGel for mucosal vaccination. The new foregrounds obtained from the VIVAC data are of critical importance for the further development and exploitation of ViscoGel as an adjuvant for human prophylactic and therapeutic vaccines. The project has led to new foregrounds and to potential new collaborations for the benefit of the participating SMEs. In VIVAC, ViscoGel was proven to constitute a simple, safe and versatile adjuvant system applicable for human use.
In a wider perspective, such an adjuvant system may provide solutions to current challenges in the development of therapeutic vaccines to e.g. cancer, autoimmune diseases and allergy, as well as for the development of vaccines to infectious diseases to which efficient protection cannot be provided with present vaccines.
Ethical considerations
When studying vaccines and adjuvants, examination of immune responses generated in vivo is necessary. Thus animal experiments were essential for the successful performance of VIVAC. Furthermore toxicity studies are compulsory for medical application products. When developing therapeutic vaccines, relevant disease models are needed. In VIVAC a mouse model for birch pollen allergy was developed. The animal experiments in VIVAC have been carried out according to the fundamental principle of the 3Rs (Replace, Reduce and Refine) for work with animals. Approvals for animal experiments were obtained from the local ethics committees for animal welfare in France, Spain, Sweden and UK.
Implementation of the 3Rs:
- Replacement: various in vitro methodologies used when possible, e.g. SLIT formulations were screened in human monocyte derived DC cultures.
- Refinement: mice anesthetized appropriately before sacrificing for collection of tissues; animal accommodations meeting the needs of the animals including nesting, 12-/12-hour light/dark cycle and with food and water ad libitum.
- Reduction: the number of animals kept to a minimum by use of inbred strains and standardized procedures for treatment and analysis.
The clinical trial was conducted in accordance with the ethical principles originating in the Declaration of Helsinki in its latest version (the 52nd WMA General Assembly, Edinburgh, Scotland, October 2000), and in consistence with GCP and applicable regulatory requirements.
Swedish laws (in compliance with the Declaration of Helsinki) were followed concerning the collection, storage and experimental use of human material and for electronic data confidentiality, security and integrity. All study subjects gave their informed consent to participate in the study.
Data and safety monitoring was conducted by a data safety monitoring board (DSMB). The trial protocol and amendments to the protocol, the Investigator's Brochure, the study subject information and informed consent form and subject recruitment procedures were evaluated and approved by the local Ethics Committee at Karolinska Institutet in Stockholm. Approval from the medical product agency was required and was obtained from the Swedish MPA.
Potential Impact:
Potential impact of project results
Despite the undisputable success of vaccines and vaccine programs in the battle against infectious diseases several challenges still remain. The unmet needs include both therapeutic vaccines to e.g. cancer, autoimmune diseases and allergy, and prophylactic vaccines to several infectious diseases. Examples of diseases to which efficient vaccines are still lacking include malaria, tuberculosis and HIV- infection/AIDS, collectively responsible for millions of deaths every year. A group of patients with a particular need for efficient vaccines is the worldwide growing elderly population. Individuals over the age of 65 often get insufficient protection from current vaccination to e.g. seasonal influenza and pneumococcal infections. Thus there is a need for vaccines able to elicit efficient and appropriate immune responses.
New vaccines developed today are often based on subunits that do not have a strong effect on the immune system. Moreover, in the situation of a pandemic, shortage of vaccine doses is an actual threat. In the case of therapeutic vaccination, modulation of an established pathological immune response is required. Depending on the indication, the vaccine has to break immune tolerance (cancer vaccines), induce self-tolerance (autoimmune diseases) or elicit appropriate non-pathogenic responses or tolerance (allergy). Thus safe and efficient adjuvants able to promote strong and appropriate immune responses are urgently needed.
Technology platforms for adjuvants fulfilling the requirements listed above have the potential to provide solutions to the unmet needs for novel prophylactic and therapeutic vaccines. This would influence health and quality of life for hundreds of millions of people worldwide, having a great socio-economic impact. Novel innovative adjuvant platforms also offer new opportunities for the vaccine market. Supporting such technology development at the European level will increase Europe's strength and competitiveness in this highly interesting and expanding market.
In VIVAC, the ViscoGel technology was proven to constitute a simple, safe, versatile and clinically applicable adjuvant system matching the requirements for a novel promising adjuvant platform. If successfully implemented the project results may thus contribute to:
- preventing shortage of vaccine supply, by reducing antigen needed per dose;
- improved protection against infectious diseases for which available vaccines have poor efficacy;
- development of therapeutic vaccines leading to improved quality of life, treatment and clinical outcome for patients with allergy or cancer;
- decreasing the societal costs in Europe and world-wide; and
- expand the vaccine/adjuvant market in Europe, leading to new opportunities for employment.
Impact for the participating SMEs
1) Viscogel AB (Partner 1): The successful development of ViscoGel as a medical product approved for clinical use, together with the positive outcome of the clinical trial will facilitate future applications of ViscoGel as adjuvant in human vaccines. In addition, through the preclinical studies performed within VIVAC, important information has been gathered on the mode of action for ViscoGel as adjuvant. This knowledge will promote further research and development on vaccine design. An exploitation plan has been set up for the use of ViscoGel, including a business model for the development of a commercial product(s).
2) Lytix Biopharma AS (Partner 2): Lytix Biopharma contributed to VIVAC with their background technology, a novel type of cationic peptides with cell-penetrating capacity. It was hypothesised that the cationic peptides could enhance the mucoadhesiveness of mucosal vaccine formulations. Furthermore, the cell-penetrating activity would increase the epithelial penetrating capacity of vaccine formulations intended for mucosal administration. In VIVAC the peptide LTX-315 was evaluated for the target application therapeutic allergy vaccination. LTX-315 has so far been applied in cancer treatment, since this type of peptides possesses strong anti tumour activity. In VIVAC LTX-315 was successfully formulated with ViscoGel and Viscosan (Viscogel's proprietary chitosan). Both LTX-315 alone and the ViscoGel/Viscosan formulated peptide were evaluated for potentially advantageous characteristics for application in sublingual allergy vaccination (SLIT). Although LTX-315 generated a slightly enhanced immune stimulation after sublingual delivery of a model allergen, this application of LTX-315 was not considered promising enough to pursue further development. Discussions were initiated between Lytix and Viscogel on other possible collaboration opportunities beyond VIVAC (subject not disclosed) and a dose-finding experiment for ViscoGel and LTX-315 was performed during the VIVAC project. Except for formulation development no new IP had been generated at the end of the project.
3) Inmunotek SL (Partner 3): Inmunotek is focused on the development and commercialization of innovative approaches to allergy diagnosis and treatment using non-recombinant (purified) and recombinant allergens. The key goal is to eliminate the drawbacks of conventional allergy treatment with unpurified natural extracts. In VIVAC Inmunotek's allergen technology was combined with Viscogel's adjuvant technology with the aim to develop new therapeutic allergy vaccines. Preclinical characterisation was performed on the immune response to both recombinant birch pollen allergen Bet v 1 and a purified birch pollen extract enriched for natural Bet v 1 in formulations with ViscoGel. It was found that ViscoGel might be a promising adjuvant candidate for use in subcutaneous allergy vaccination (SCIT). Further development is needed in order to obtain new IPRs in this area. VIVAC has generated scientific collaboration between Inmunotek and Karolinska Institutet (Partner 7) on allergen characterisation and between Inmunotek and Viscogel on a cancer vaccine project.
Dissemination of project results:
VIVAC project results were managed with the following objectives:
- to generate and protect new IPRs
- to present results at scientific conferences and in peer-reviewed journals
- to promote collaboration between VIVAC partners and to attract new collaborators and partners
- to support out-licensing of product candidates
Dissemination of results
All participants in VIVAC are entitled to publish project results after review by the VIVAC steering committee (SC, consisting of representatives for the three SMEs). The SC has the right to delay a publication for a reasonable time period in order to ensure appropriate action if the data to be presented could be the subject matter of intellectual property protection. The funding by the FP7 program 'Research for SMEs' has been, and will be, acknowledged in all publications and presentations of VIVAC results.
VIVAC results have so far been presented at the following vaccine/adjuvant-, allergy- and chitosan conferences:
- IMV (Modern Vaccines Adjuvants & Delivery Systems) in Porto, Portugal, April 6-8, 2011
- EAACI (European Academy of Allergy and Clinical Immunology) meeting in Istanbul, Turkey, June 11-15, 2011
- 4th International Conference on Drug Discovery & Therapy, Dubai, United Arab Emirates, 12-15 February 2012
- IAMV (Modern Vaccines Adjuvants & Delivery Systems), Copenhagen, Denmark, July 4-6, 2012
- 6th IberoAmerican Chitin Symposium / 12th International Conference on Chitin and Chitosan, 2-5 September, Fortaleza, Brazil
One report on VIVAC results has been published in a peer-reviewed journal:
- Neimert-Andersson T., et al. 'Improved immune responses in mice using the novel chitosan adjuvant ViscoGel, with a Haemophilus influenzae type b glycoconjugate vaccine' Vaccine, (2011) 29:8965-73
Additional publications will result from VIVAC. Publications of mechanism of action for ViscoGel as adjuvant and on clinical trial results are planned. Viscogel AB has published three press releases directly related to the VIVAC project.
Scientific /business collaboration
To support the collaboration between the VIVAC project partners three VIVAC project meetings have been organised:
- VIVAC Kick-off meeting in Stockholm, September 2-3, 2010
- VIVAC Half-time meeting, Istanbul, June 10-11, 2011
- VIVAC Final project meeting, Stockholm, April 16-17, 2012
Collaborations have been initiated between the SME partners, as described above. In addition Viscogel has together with Karolinska Institutet received a four years grant from the Swedish Research Council to a PhD student who will be funded during four years to investigate immune mechanisms of action for ViscoGel. These partners (KI and Viscogel) have also started collaboration on the development of allergy vaccines with ViscoGel. The VIVAC project consortium has provided a scientific/business network for potential future collaborations between project participants.
As a result of the presentations and publication of preclinical results on ViscoGel as an adjuvant, collaborative and business agreements have been established between Viscogel and vaccine companies, both within veterinary and human medicine.
IPR management
The IPR strategy to define pre-existing know-how, the establishment and protection of intellectual property (IP) and ensuring confidentiality of information shared in the VIVAC project have been critical activities to ensure a successful commercialization of the results.
The process for handling IPR in VIVAC was regulated by the grant agreement, stating that the ownership of the project results will remain with the SMEs and the RTD performers should be remunerated 100% for their work. During the VIVAC project the results have been carefully evaluated to make sure that novel IPR opportunities will be protected. No applications for novel intellectual property rights (patent applications, trademark rights etc.) have been filed during the VIVAC project. The results/foreground obtained in VIVAC will though constitute a valuable foundation from which new IPRs and out-licensing of products/technologies will be managed according to the business model of each SME.
Exploitation of results:
The target applications of the VIVAC project i.e. i) prophylactic vaccination against common infectious diseases, and ii) therapeutic allergy vaccination, both represent billion EUR markets. A successful outcome of the VIVAC project would significantly improve the competitive situation for the SME partners and create new commercialisation opportunities.
Market segments, vaccine market
Prophylactic vaccines
Expansion of the vaccine market is primarily driven by new innovations and increased market growth, which is in part driven by the focus on infectious diseases and the threat of pandemics from new types of influenza. The market has also proved willing to pay higher prices for more effective products. The rapid growth, approximately 30 percent per year during the period 2004-2007, can be compared with the figure of 8 percent annual growth for the pharmaceutical industry as a whole. CAGR during the period 2007-2017 is expected to be 11.5 percent. Vaccine sales during 2010 are estimated to USD 28 billion according to GBI Research. Following a number of structural deals, the vaccine market has come to be dominated by the major pharmaceutical companies (Big Pharma), which currently account for about 85 percent of the total vaccines market. Sales of vaccines in the veterinary market are estimated at USD 5.9 billion (GBI Research) with annual growth of about 1 percent.
A large part of successful development in the vaccine field has been through the development of more efficient adjuvants. ViscoGel's properties provide the potential for improved adjuvants that can be utilized for improved and entirely new vaccines for both human and veterinary medicine.
Therapeutic vaccines The market for therapeutic vaccines has great potential to add new treatment concepts in many indication areas, including allergies, nicotine addiction, autoimmune and cardiovascular diseases. A substantial number (hundreds) of products are under development and a few of them have reached the market like Provenge, a prostate cancer vaccine approved in the US and Oncophage, a kidney cancer vaccine approved in Russia.
The high incidence of allergic diseases has highlighted the need for efficient treatments, and the allergy vaccine area has been assessed as an interesting market. It is estimated that 10-30% of the population in the US and at least 20% in Europe suffers from allergic rhinitis. According to the World Allergy Organization report in 2008, approximately EUR14 billion are spent globally each year on allergic rhinitis and in 2007, the total incremental cost of asthma to society in the US was $56 billion (Barnett and Nurmagambetov, J Allergy Clin Immunol 2011). Birch pollen allergy affects approximately 20% of the population in exposed areas, e.g. in central and northern Europe (European Community Respiratory Health Survey, 2007).
Safety risks, long treatment time and complex dosages have prevented more widespread use of allergy vaccines. Most patients today exclusively receive symptomatic treatment. Medications in fact represent the largest cost component of direct medical expenditures for asthma and rhinitis. Thus it is of importance to weigh the costs for a lifelong consumption of drugs against the cost for allergy vaccination. Over longer time periods it has been shown that patients treated with SCIT or SLIT vaccination display a lower mean annual cost than patients who only receive symptomatic treatment. The anti-allergy drug market is anticipated to exceed 14.7 BUSD by 2015 in the US alone according to GIA. Worldwide allergy vaccine sales were 642 MUSD in 2010 and could be worth billions if new technologies succeed in achieving long-term relief of symptoms, significant cost advantages compared with medication and more convenient dosage as necessary for practical use. One can anticipate that allergy vaccines will prove cost-effective in the long run and could thus also improve the overall health economics.
Potential partners
The vaccine market is currently dominated by five large players, Merck&Co, Sanofi Pasteur, GlaxoSmithKline, Pfizer and Novartis. MedTrack databases list over 500 vaccine companies with vaccine candidates in development.
While Big Pharma dominates the market for vaccines to end customers, much of innovative technical development is performed by smaller biotechnology companies with which the major companies are interested in creating alliances. Examples of such alliances include the close collaboration between Intercell AG with both Novartis and GSK with regard to the IC-31 adjuvant and the collaboration between Sanofi and Crucell on new production methods for influenza vaccines. Big Pharma has an obvious interest in new market best-sellers and these have been achieved through acquisitions and alliances for specialized vaccines such as Prevnar (Pfizer), Gardasil (Sanofi Merck) and Cervarix (GSK).
Competitors
Several competing adjuvants are in the process of development, but only four adjuvants are currently found in approved vaccines globally. These are:
- Aluminiumhydroxid (alum) has been a standard for adjuvants since the beginning of the 1900s. A consensus exists in the industry that a need exists for improved adjuvants capable to induce cellular responses
- AS03 (GSK), which is based on squalene and used in Pandemrix for H1N1 vaccination. Not approved for use in the US.
- AS04 (GSK), which is based on aluminum hydroxide and monophosphoryl lipid A (MPL) and used in hepatitis and HPV vaccines.
- MF59 (Novartis), which is based on squalene and used in influenza vaccines. Not approved in the US.
The main competition of a novel therapeutic allergy vaccine is conventionally used therapeutic drugs targeting the allergy symptoms. The anti-allergy drug market is currently dominated by antihistamines, which represent the most widely prescribed anti-allergy products, followed by corticosteroids.
VIVAC business model
Exploitation strategy of results
The strategy is to market novel technologies to leading global companies in vaccines, pharmaceuticals and drug delivery. The business model builds on initially demonstrating Proof-of-Concept (PoC) for the selected application areas, that is, clear data to demonstrate that the technology works. Based on this data and the SME's intellectual property rights, potential partners are identified for further evaluation, development and commercialization. The partnerships are facilitated by license or collaboration agreements with a revenue model that includes upfront payments, milestones and royalties.
Profiling and searching for partner opportunities Potential partners are sought within the existing network as well as search databases (e.g. MedTrack, Thompson Pharma) to identify vaccine companies worldwide, with a potential need for novel technologies. Based on the ideal profile of a partner the search strategy is progressively refined. The search results are then segmented into indication areas, development phase, size etc. down to a limited target list of vaccine company contacts that will match the need of an ideal partner to SME.
Evaluation phase
Most likely the Due Diligence phase and business negotiations are preceded by an evaluation phase where the collaboration partner will test the adjuvant technology pre-clinically in combination with their own vaccine candidates, which are in development. These R&D collaborations may enhance the interest of the SME's technologies within the company and also enable identification of novel future product candidates and business opportunities. The evaluation phase will be implemented under Material Transfer Agreements (MTA) as well as R&D Collaboration Agreements. A successful outcome of the evaluation phase will add value to the SME and increase the chances of continued successful term sheet negotiations
Deal management
The final deal or deals can be structured in many ways depending on how to address different complex situations. The main types of structure will be licenses, acquisitions and joint ventures.
Alliance management making the deal work
The most likely outcome during the commercialization is license agreements where the SME's license the IPR related to the technology to a larger vaccine development company with financial capacities to continue the development into a marked product. The license agreement will not only be a plain license but rather a strategic alliance between the companies where the continued collaboration and effective development is of great importance. Successful alliance management is the key to ensure the continued development and commercialization of the new product based on the SME's technologies.
Exploitable results from VIVAC (New/Exploitable foreground; Description, Utilization)
1) Characterisation data on Viscosan and ViscoGel; Supporting the regulatory documentation on Viscosan/ViscoGel.
2) ViscoGel manufacturing; Process development resulting in a GMP manufacturing process.
3) Formulation development; New improved formulation processes and analyses. Data on ViscoGel formulation with Bet v 1, LTX-315, OVA and Act-Hib.
4) Toxicity data obtained in mice and rabbits; Supporting regulatory documentation for clinical use.
5) Preclinical POC for ViscoGel as adjuvant; Data obtained on the innate and adaptive immune response induced by ViscoGel will be of importance for further development of ViscoGel based vaccines.
6) POC data in man for ViscoGel as adjuvant; Exploitation of ViscoGel as adjuvant for human vaccines.
Concluding remarks on potential impact, dissemination and exploitation of results
There is a considerable global need for new vaccines that are able to induce efficient protection to infectious diseases. An adjuvant enhances the efficacy of the vaccine and lower the production cost through reduction in the quantity of antigen. In total only four adjuvants have been licensed in the EU and US. There is thus a significant opportunity for new adjuvants. Indeed, in later years the prospects for the global vaccine market have dramatically improved and significant growth potential is indicated. Vaccination strategies are also sought for therapeutic indications e.g. cancer and allergy, where the adjuvants' immunomodulatory capacity represents a significant exploitation possibility.
In VIVAC, the ViscoGel technology was proven to constitute a simple, safe, versatile and clinically applicable adjuvant system matching the requirements for a novel promising adjuvant platform. Such a platform provides means to increase the efficacy and duration of a vaccine. In addition it will potentially reduce the costs for manufacturers and payers, and improve the supply in a pandemic, which is of interest to governments and global health organizations.
Several new foregrounds were obtained during the VIVAC project, supporting the development of ViscoGel as an adjuvant for prophylactic and therapeutic vaccines. The positive results from the Phase I/II clinical trial for ViscoGel as adjuvant in man have paved the way for new partnering agreements with vaccine companies. Valuable scientific collaborations and potential new partner contacts have been generated for the participating SMEs. The novel results/foregrounds will constitute an important foundation from which new IPRs and out-licensing of products/technologies will be managed.
In conclusion, the VIVAC project has significantly improved the competitive situation for the SME partners and created new commercialisation opportunities. On a societal level, the development of an adjuvant technology applicable in novel prophylactic and therapeutic vaccines will have a potential impact on health and quality of life, as well as a beneficial effect on health economics.
Project website: http://www.vivac.se
