Final Report Summary - MYASTERIX (Clinical safety, immunogenicity and efficacy of a therapeutic vaccine that combines peptides mimicking antigen receptors on autoimmune B and T cells associated with myasthenia gravis)
Executive Summary:
MYASTERIX project aimed to advance a therapeutic vaccine candidate (CV-MG01 with orphan drug status) for the autoimmune disease Myasthenia Gravis (MG) to human proof-of-concept studies. The final goal is to provide a more targeted therapeutic approach with fewer and less severe side effects than the existing therapeutics.
The project was initially divided into 6 main Work Packages, WP1 management, WP2 production, WP3 toxicity study, WP4 phase 1B clinical trial, WP5, phase 2B clinical trial, WP6 exploitation and dissemination.
During the last amendment, the WP7 Additional non-clinical studies, was added.
The WP2, WP3, WP4 were successfully delivered. The WP5 could not be delivered on time and was replaced by the WP7. The WP6 was mainly delivered.
During the course of the project, the consortium was able to manufacture the peptides, the conjugates and the vaccine components (antigen and adjuvant) and demonstrate their stability over three years (WP2). Some unforeseen solubility issues have been solved during the project leading to a more consistent production process.
The GLP regulatory toxicity studies were successfully done on time (WP3).
The very good safety profile of the therapy was documented as part of the phase 1b clinical trial on 24 myasthenic patients (WP4). The recruitment lasted one year in one centre, which represents record high recruitment rates for such a disease. Although lower than expected, immunogenicity to the vaccine components was achieved.
The study design and other factors did not allow drawing any efficacy conclusions on the therapy: meaning that no proof of efficacy could be documented as part of this phase 1b study.
The second clinical study, which should have been a confirmatory trial (WP5) could not take place due to the lack of on-time approval by the ethics committee of the partner that should have carried out the main part of the clinical trial although it was approved by the Belgian regulatory authorities and the UZA Ethics Committee.
Most of the tasks for exploitation and dissemination were successfully delivered: the market study, the communication tools, the contacts with the regulatory authorities (EMA) and the patients’ association and the scientific communications.
For the exploitation part, a term sheet with potential investors is still being negotiated.
In conclusion, the Myasterix project advanced a therapeutic vaccine candidate to first-in-human studies and showed its excellent safety profile. This project allowed opening the way to a proof of concept of this therapy and the future developments.
Project Context and Objectives:
Concept:
The concept developed in this 5-year SME-led project was to advance a therapeutic vaccine candidate (CV-MG01 with orphan drug status) for the autoimmune disease myasthenia gravis (MG) to human proof-of-concept studies.
The objectives were defined as follows:
(1) to manufacture according to the appropriate guidelines, batches of the candidate vaccine for toxicology and clinical studies,
(2) to carry out preclinical toxicity testing of the product following Good Laboratory Practice guidelines and initiate stability testing;
(3) to gain approval for and perform a phase I clinical trial during the third and fourth years to demonstrate safety, tolerability and immunogenicity of the MG therapeutic vaccine candidate
(4) to gain approval for and perform a phase II clinical trial during the fourth and fifth years of the project to demonstrate efficacy and achieve proof of concept of the proposed therapy. In case the phase II trial could not be performed, the goal was to replace it by accumulating proof of mechanism of action data in vitro (with the biological material generated during the phase 1 study) and in vivo on animal models.
Myasthenia gravis
Myasthenia gravis (MG) is a neuromuscular disorder in which functional acetylcholine receptors (AChR) become depleted at neuromuscular junctions due to an antibody-mediated autoimmune attack on the neuromuscular synapse. AChR antibodies can be detected in the serum of ~90% of patients with generalised MG. It is a rare orphan disease with a prevalence of 1.6–2 per 10,000 people and an incidence of 1.2–1.5 per 100,000 people in the EU.
Current treatments include symptomatic pharmacotherapy, immunosuppressive medication, immunomodulating therapies and a surgical procedure (thymectomy). Symptomatic pharmacotherapy using acetylcholinesterase inhibitors increases the availability of acetylcholine (ACh) at the neuromuscular junctions. Immunosuppressive medications include prednisone, cyclosporine, azathioprine, mycophenolate mofetil and occasionally cyclophosphamide. Immunomodulating approaches include plasmapheresis and the use of intravenous immunoglobulin (IVIg).
The pathogenesis of MG can be attributed predominantly to IgG antibodies against the α-chain of the nicotinic AChR, often targeting residues 61-76, which is known as the main immunogenic region (MIR) (Weathington et al., 2003). The T-cell dependency of pathogenic anti-MIR antibodies is supported by: (1) the IgG isotype of anti-AChR antibodies (with an isotype switch from IgM to IgG); (2) the relative benefit of thymectomy; and the ability of antibodies against (3) cluster of differentiation 4 (CD4) and (4) major histocompatibility complex (MHC) class II, to improve experimental autoimmune myasthenia gravis (EAMG) in rats.
Given the central role of autoantibodies in MG pathogenesis, targeted reduction of specific anti-MIR antibodies should considerably improve or even normalise the functionality of the neuromuscular junction in MG patients.
Proposed therapeutic vaccine
The vaccine candidate comprises two synthetic peptides. RhCA 67-16 is designed to generate antibodies (anti-idiotypic Abs) that bind autoantibodies (idiotypic antibodies, Id Abs) and RhCA 611-001 is designed to generate antibodies that bind T-cell receptors (TCRs). Each peptide is separately coupled to CRM197, a genetically detoxified diphtheria toxoid (DT) carrier. The conjugated peptides are mixed with a saline solvent and adsorbed to the alum adjuvant.
Mechanism of action
The proposed treatment follows the molecular logic of antigen receptor mimetic (ARM) vaccination for autoimmune diseases reviewed by Weathington and Blalock (2003). For MG, the autoimmune assault on the nicotinic AChRs of skeletal muscles often causes a severe deficit in muscle function due to the destruction of muscular tissue architecture at the neuromuscular junction. The main B-cell epitope on the AChR (MIR, see above) is probably targeted by molecular mimicry, leading to the loss of self-tolerance for the nicotinic AChR and the generation of Id Abs. T-cell sensitisation to a T-cell epitope on the nicotinic AChR (α-subunit residues 100-116) is thought to promote cytokine-mediated B-cell isotype switching and the production of circulating anti-AChR IgG antibodies (detectable in ~90% of MG patients). By vaccinating with the ARM vaccines for each epitope, we aim to generate antibody responses that react against the pathogenic Id Abs (anti-idiotypic Abs) and to the TCR for T-cell clones reactive to nicotinic AChR (anti-TCR Abs), thus reducing pathogenic anti-MIR antibody responses and restoring function at the neuromuscular junction.
The Abs reactive with the B epitope are reactive to the B cell Ag receptor and bind and annihilate circulating Abs (Araga et al., 1993, 1996 see summary hereunder) while the Abs reactive with the T cell Ag receptor seems to inhibit T cell proliferation and induce regulatory T cells (TREG). The administration of monoclonal Ab (mAb) derived from vaccinated animals and reactive with Vb15+ TCR specific for AChR 100-116 has been shown in vitro to block proliferation of target T cells while also changing cytokine profile, decreasing IFNγ, increasing IL-10 and increasing the percentage of CD4+ CD25 T cells pointing to the action of TREG (Xu et al., 2001).
Why the proposed vaccine should work in MG patients
Myasthenia gravis is a T-cell dependent, B-cell mediated autoimmune disease and therefore both T-cell and B-cell epitopes responsible for anti-MIR antibodies were to be targeted using a combined therapeutic vaccine based on the complementary RhCA 67-16 and RhCA 611-001 peptides.
Treatment with the proposed therapeutic vaccine specifically targets the underlying immune disorder in the EAMG rat model and in the spontaneous MG canine model. The vaccine candidate therefore has the potential to preserve immune system function in MG patients while treating the underlying pathology.
Objectives:
Production of preclinical and clinical GMP batches
Existing SOPs for the manufacture of the human formulation of CV-MG01 were used to produce a preclinical GMP-like batch which has been tested for immunogenicity in healthy rats. It was planned that technology transfer from CuraVac to piCHEM would be implemented, followed by the manufacture of batches for toxicology studies and clinical trials. Stability studies would then be carried out according to the International Conference on Harmonisation (ICH) guidelines on the drug substance and the drug product, on three batches (preclinical, phase I and phase II).
Preclinical toxicity study
A GLP toxicology programme consistent with CPMP/ICH/286/95 and CPMP/SWP/465/95 was planned to be carried out using 40 rats which would receive the highest planned human dose (not per weight ratio) injected four times (one time more that the planned human schedule) using the schedule that yields the best immunisation in rats (15-day intervals between injections). Half of the rats were to be sacrificed the day after the last immunisation and the other half 15 days later for toxicity assessment. Complete necropsy and anatomopathology would then be performed.
Phase I clinical trial
A complete clinical trial application (CTA) compiling the investigational medicinal product dossier (IMPD), the investigator brochure (IB) and the other necessary documents was planned to be submitted to the Dutch ethical and competent authorities. After a refusal by these, a contingency procedure was activated. A new University Hospital partner was integrated in the Consortium (UZA) and the CTA was successfully submitted to the Belgian competent authority and the Ethics Committee of the Hospital (UZA).
A first-in-human clinical trial was to be carried out in MG patients to assess the safety, tolerability and immunogenic response following subcutaneous injections of CV-MG01. The trial was to be designed as a human pharmacology and therapeutic exploratory, dose escalation, parallel group, randomised, placebo-controlled, multiple treatment, single centre, investigator and subject-blind study using adaptive dose and sample size approaches.
It was planned that each subject would receive three subcutaneous injections at weeks 1, 4 and 12 in a study that lasts 16 weeks per subject. Each subject would receive 18 µg of the B peptide and 60µg of the T peptide for the low dose and 60µg of the B peptide and 200 µg of the T peptide for the high dose, the former corresponding to the peptide dose in the dog trial (500 µg of conjugate, ~20 µg of peptide equivalent) and the latter corresponding to a dose that has been used for peptide vaccines in previous clinical studies to elicit strong immunogenicity (Cytos Biotechnology in hypertension, NicVax in nicotine addiction). The placebo was to be the adjuvant alone (making the blinding feasible as the adjuvant and adjuvanted vaccines are both white colloidal suspensions). The aim was to carry out the trial at UZA (University Hospital Antwerp) with partner 5 (Aepodia) managing protocol development, submissions, site management, statistics, data management, pharmacovigilance, clinical study report (CSR) preparation and quality assurance for good clinical practice (GCP) compliance.
Phase II clinical trial
A phase II proof-of-concept (POC) study was planned in MG patients to assess clinical efficacy following subcutaneous injections of CV-MG01.
The trial was designed as a therapeutic confirmatory, parallel group, randomised, placebo-controlled, multiple treatments, single centre, investigator and subject-blind. The dosing scheme (i.e. three injections) will be the same as that in the first-in-man trial, although potentially could be adjusted depending on the findings. The initial objectives were:
• To evaluate the efficacy of the treatment using the MGC scale and clinical evaluation, and to demonstrate the proof of concept of the vaccine.
• To assess the immunogenic response to CV-MG01 by monitoring RhCA 611-001 and RhCA 67-16 antibodies and the effect on the plasma level of AChR Ab, and to demonstrate the expected mechanism of action of the vaccine.
• To monitor the safety and tolerability of CV-MG01.
As a contingency procedure, in case the phase II clinical trial is not approved on time to be finished during the project allocated time, the phase II clinical trial was planned to be replaced by additional non-clinical studies taking into account the results of the phase I and targeting to accumulate proof of concept data in vitro and in vivo.
Dissemination and exploitation
This EC project aimed to address an important funding gap for early-phase therapeutics, especially in orphan diseases, but several investors and pharmaceutical companies have indicated that once the project has reached human proof-of-concept, they are willing to invest in the project or the company, or to licence-in the vaccine. In the first three years of the project, Myasterix aimed to gain more data to consolidate the corresponding business plan whereas in the last two years, once initial results become available, discussions and negotiations with potential investors would commence. This was to guarantee an immediate transition from public to private investment, which is required to finally reach the market.
The vaccine development plan was to be fine-tuned at this stage by contact with patients’ associations and the regulatory authorities (EMA) to validate the anticipated target product profile and define the number of patients needed in phase III trials (currently estimated to be 120). The target product profile (TPP) would also be adapted throughout the project, based on preliminary clinical trial results.
Better production process knowledge will also allow us to evaluate process validation and market manufacturing costs for the vaccine, and thus verify the cost side of the project business plan (clinical development and manufacturing costs). Detailed market analysis will be carried out to provide a robust evaluation of the market size and product reimbursement price, thus verifying the revenue side of the project business plan.
With these studies and reports, the consortium will have confidence in the product valuation which will facilitate contacts with potential licensors and investors (pharmaceutical and biotechnology companies, or venture capitalists).
Project Results:
The main results of the project are described below per Work package.
WP2 Production
WP2 was organized into 8 tasks. The main results of each task are summarized below.
Task 2.a: Process transfer and small-scale test batches
During the first period of the project, the technology transfer from CuraVac to piCHEM was completed. A revised protocol for the conjugation has been evaluated in order to compare the different methods in a comparative immunogenicity study.
Task 2.b: GMP production of peptide antigens
Peptide antigen T-Peptide has been synthesized in R&D-grade and GMP-grade quality at large scale, whereas B-Peptide was synthesized at GMP-grade quality in large scale. For the production of the corresponding conjugates for the toxicity study T-Peptide in R&D-grade and B-Peptide in GMP-grade quality were used.
All synthesized batches were released by piCHEM’s Quality Control (R&D-grade peptide) and Qualified Person (GMP-grade peptides) according to their specifications. CuraVac approved the specifications of the peptide antigens. As sponsor of the clinical trial, CuraVac audited piCHEM for GMP compliance.
Task 2.c: Production and quality control of toxicity batches
For the production of the vaccine for the toxicity study two conjugates (T-Peptide-CRM and B-Peptide-CRM) have been produced and released according to the previous designed method (task 2.a.). Carrier Protein CRM197 has been activated by the heterobifunctional cross-linker GMBS to present a linkage group between the protein and the antigenic peptides. Both, unreacted GMBS and unreacted peptides have been removed by several ultrafiltration and centrifugation steps. The two conjugates (drug substance) have been formulated as lyophilisate without any buffer salts. Swiss company Baccinex was subcontracted for the final fill and finish process of the vaccine (drug product).
The vaccine was designed as a two-component kit:
• Component 1: CV-MG01 Antigen; consists of the mixed conjugate (T-Peptide-CRM and B-Peptide-CRM) freeze dried together with Mannitol
• Component 2: CV-MG01 Adjuvant; consists of Alhydrogel suspended in NaCl solution
Both components were analysed and released by the QC unit of piCHEM.
Task 2.d: Production of the phase I GMP drug substance batch
It was decided that the GMP drug substance batch should be produced and formulated identical to the toxicity batch as a two-component kit: CV-MG01 Antigen and CV-MG01 Adjuvant.
For the clinical phase I study the starting material (carrier protein CRM197 and the two peptides T-Peptide and B-Peptide) were used in GMP-grade quality. The conjugates were produced by piCHEM and both drug substances were shipped to Baccinex for the final fill & finish at the end of Nov 2014.
Task 2.e: Final formulation GMP vaccine for clinical phase 1
Final formulation of the GMP vaccine for the clinical phase I study was subcontracted to the company Baccinex. Some challenges were encountered with filtration and the operation had to be repeated on a second batch with separate filtration of the B-peptide and T-peptide conjugates.
Task 2.f: Stability study of GMP drug product batch for clinical phase I
All QC released intermediates and final products were subjected to stability studies at different temperatures and different durations. piCHEM performed all the stability studies. The stability protocol was checked and agreed by CuraVac.
In the final period of the project, the stability studies were finalized and additional non-GMP batches of the conjugates were manufactured to support the non-clinical studies. The compatibility of more potent adjuvants with the new formulation was tested.
The stability studies enabled the shelf-life extension of the product used in the clinical trial at UZA. The antigen and the adjuvant vials now have a proven stability of three years.
Task 2.g: Production of the phase II GMP drug substance batches
In February 2016 it was decided to start the production of both the B-Peptide and the T-Peptide in GMP-grade quality. These peptides served as starting material for the production of R&D-grade conjugates (B-Peptide-CRM, T-Peptide-CRM) for further solubility and formulation studies.
Both peptides could also have served as starting material for the production of phase II GMP drug substance batches in case of need, but the priority was focused on solving the low solubility of the conjugates with the current formulation.
The production of both peptides was performed by piCHEM; the B-Peptide was released on 27th of July 2016, whereas the T-Peptide was released on 30th of August 2016.
Besides these considerations, it was also decided that the drug substance and product for the clinical phase II could be the same as the ones for the phase I thanks to the good stability data obtained on the products and thanks to the sufficient number of vials (see also task 2.h here under).
Task 2.h: Final formulation GMP vaccine for clinical phase II
No final formulation of the GMP vaccine for phase II was needed.
It was decided to use the left-over vials from the production of the GMP vaccine (CV-MG01 Anti-gen BatchNo AB8-150504 and CV-MG01 Adjuvant BatchNo AB9-141102) manufactured for the clinical phase I also for clinical phase II (which did not take place in the end)
Task 2.i: Stability study of GMP drug product batch for clinical phase II
It was decided that GMP drug product batch produced for clinical phase I would also be used also for clinical phase II, so no new stability study was required. However, data from the stability study of the GMP drug product batch for clinical phase I was to be used. Phase II did not take place.
WP3 Toxicity study
To conduct the toxicity study, the consortium referred to the WHO guidelines for vaccines and adjuvants “Guidelines on the nonclinical evaluation of vaccine adjuvants and adjuvanted vaccines” from October 2013 which was not available at the time the proposal was written.
The toxicology was performed at an Association for Assessment and Accreditation of Laboratory Animal Care (AAALAC) facility with the toxicology batch supplied by piCHEM. Immunogenicity tests showed that the vaccine components generated their intended pharmacological action in the animals.
No adverse events were reported during the in-life phase and no differences were reported between the control group and the groups that received the vaccine or the components in terms of systemic toxicity. After full necropsy, no general adverse findings were reported.
The conclusions of the toxicity report were also used in the Clinical Trial Application for Phase I.
Task 3.a: Final CRO selection
Several CROs were contacted for the toxicity study and CiToxLAB was selected.
Task 3.b: Protocol writing and approval
The in vivo phase protocol was developed on the basis of the new WHO guidelines. Careful consideration was given to the choice of animals. Rats were an obvious choice for the project because many pre-clinical studies assessing the efficacy (the EAMG model) but also the immunogenicity studies of the vaccine were done on rats. The immunological detection tools (ELISA) were also already developed for rat sera. The number of animals was set at 30 per group according to the new guidelines and the number of groups was limited to three because we use the well-known adjuvant aluminium hydroxide which is used in numerous approved vaccines.
The protocol was approved early August 2014.
Task 3.c: Study in-life phase
The in-life phase was managed as planned in the protocol with the first injection on the 11th of August 2014 and the last sacrifice on the 10th of October 2014.
Task 3.d: Final report writing
The final QA approved report was sent by CiToxLAB in April 2015 and was made available to the regulatory authorities.
WP4 Phase 1b clinical trial
Task 4.a: Protocol development and submissions
The first Clinical Trial Application (CTA) prepared by CuraVac, Aepodia, LUMC and piCHEM was presented to the Dutch competent authorities and was refused in July 2015 after an appeal by the Sponsor representing the Consortium.
As a contingency plan, it was decided to include a new University Hospital partner in the Consortium to submit a slightly revised protocol to the Belgian competent authority and UZA, as new Partner, Ethics Committee.
The second Clinical Trial Application (CTA) prepared by CuraVac, UZA, Aepodia, LUMC and piCHEM was accepted in October 2015 by the Belgian competent authority and by the UZA Ethics Committee.The study protocol CV-0002 (phase 1b), EudraCT 2015-002880-41, entitled “A first-in-human and proof-of-concept study” to assess the safety, tolerability and immunogenic response after subcutaneous injections of CV-MG01, acetylcholine receptor mimetic peptides, as potential therapeutic vaccine, in patients with myasthenia gravis was developed and designed to assess the following objectives:
- Primary objectives: To evaluate the safety and tolerability of CV-MG01 after subcutaneous injections in patients with MG and to assess the immunogenic response after subcutaneous injections of CV-MG01 on the plasma levels of B- and T- peptide antibodies.
- Secondary objectives: To assess the effect of CV-MG01 subcutaneous injections on the plasma level of acetylcholine receptors antibodies (AChR Abs) and to perform a preliminary evaluation of efficacy using clinical scales and questionnaires.
- Exploratory objectives: To explore changes in the humoral and cellular immune responses.
The study was divided into 2 parts: Part A (dosing phase) and Part B (safety follow-up phase).
It was necessary to amend the protocol at various stages of the study throughout the project. The Protocol that was originally accepted by the Belgian Competent Authority and the UZA Ethics Committee was protocol version 5. The protocol version 8 (latest version, substantial amendment) was approved by the Belgian Competent Authority and the UZA ethics committee (EC) on 29 and 20 August 2018 respectively.
Task 4.b: Recruitment and study/site set-up
A pilot study using tetanus vaccinations has been set up at LUMC. CME approval for this study was obtained and patients were recruited. The aim was to include 50 AChR MG patients and test the response to a boost with tetanus vaccine. The AChR antibody titers and the T-cell and B-cell responses were tested using the same protocol as for the phase 1b clinical trial using the CV-MG vaccine. The results of the tetanus study were published.
As soon as the consortium obtained Belgian regulatory approvals, part A of phase I clinical trial started at UZA at the beginning of November 2015. The study has been conducted at UZA hospital (Antwerp, Belgium) under the supervision of Prof. Rudy Mercelis as Principal Investigator.
The first patient entered the study on the 3rd of February 2016 with a first dose on the 30th of March 2016.
By September 2016, cohorts 1 and 2 of the CV-002 study were fully recruited (16 patients included from more than 25 patients screened). No serious adverse event was reported. 8 patients were recruited for the 3rd cohort.
In total, 25 patients were recruited in 13 months in one centre which represents a very high rate for a disease like MG. It shows the interest and expectations from the patients for a better therapy than the existing treatments.
Task 4.c: Patient vaccinations and follow-up
On the 12th of August 2016, the Interim Data Review 1 was organized (after visit 4 of the first 6 patients of cohort 1). The low dose of CV-MG01 was firstly tested on a first cohort. This low dose was deemed safe and the Data Review Committee agreed to start the injections using the high dose. The first patient of cohort 2 was injected on the 17th of August a few days after this decision.
Blinded analysis of the first set of available sera from the first cohort of MG patients showed that several patients produced antibodies to either the B-cell or T-cell peptide or both.
A second Interim Data Review meeting was organized in December 2016 to decide which dose level (high or low) will be tested in cohort 3. The first dosing (with the high dose) of this third cohort was scheduled on the 10th of January 2017.
At UZA, a total of 24 patients completed the study Part A with a last patient visit on 13 September 2017 and received the 3 subcutaneous injections (8 patients for each cohort): 6 received the low dose, 12 the high dose and 6 the placebo.
Immunogenicity (antibodies against B- and T-peptides) and safety were assessed as primary endpoints. Secondary endpoints included AChR antibody titre changes and assessment of efficacy using clinical scales and questionnaires.
The database lock for Part A (clinical and safety data) was performed on the 1st December 2017. The CV-MG01 vaccine was well tolerated and no serious adverse event occurred during study Part A.
Data revealed that some patients showed immunoreactivity against the B and T peptide. The titres rose after the first vaccination and continued to increase after the second.
The AChR titers remained stable over time for all patients. CRM197 reactivity clearly confirmed the vaccination as the titres increased throughout the study after the vaccinations.
Overall, the immunogenic response was found to be much lower compared to what was expected from animal studies.
The final results of part A confirm the excellent safety profile of the vaccine. The immunogenicity is relatively low and no conclusion on efficacy can be drawn from this first study.
Task 4.d: Long-term extension study
The first visit of part B took place on 16th of December 2016. The total duration of Part B was reduced from its original duration of two years to fit with the project timelines. All 24 patients who completed the 10 visits of study Part A had accepted to participate in the safety follow-up part of the study (Part B), the long-term extension study.
In total, all patients completed Visit 11 (4-month follow-up); 23 patients completed Visit 12 (8-month follow-up); 21 patients completed Visit 13 (12-month follow-up); 13 patients completed Visit 14 (16-month follow-up); 8 patients completed Visit 15 (20-month follow-up); 2 patients completed Visit 16 (24-month follow-up).
The safety profile of the vaccine is excellent, and no safety concern has been identified. In Part B, 1 patient reported 3 Serious AEs. These Serious AEs were considered as not related to study drug administration, since the events occurred more than 16 months after the last injection of CV-MG01 (low dose).
Task 4.e: Data analysis and clinical study report writing
The Statistical Analysis Plan v1 was prepared by Aepodia and was approved on 29 November 2017. Analyses of the primary and secondary endpoints were performed after database lock.
The Clinical Study Report of Part A was finalized by Aepodia and was approved by the Principal Investigator and Sponsor on 23 and 24 May 2018 respectively.
The last patient last visit (Part B) was performed on 28 September 2018. The Statistical Analysis Plan v2 (Part B) was prepared by Aepodia and approved on October 2018. The Database lock for Part B will be performed in December 2018 and the Clinical Study Report (Part B) is expected to be released in early 2019.
Patients had on average improved at the end of the study part A. However, no significant difference was observed between treatment groups (i.e. study low dose, study high dose and placebo) in each of the 4 scales used (i.e. QMG, MGC, MG-ADL, MG-QoL15). Moreover, 2-point MG-ADL and 3-point QMG responder rates were not different between treatment groups.
This lack of observed difference in clinical efficacy variables might be explained by 2 main limiting factors:
- Immunogenicity factor: The immunogenicity developed (i.e. generation of anti-peptide Abs following vaccine injection) might be too low to generate a significant blockade in auto-antibodies against ACh Receptor, and therefore to induce a clinical effect.
- Methodological factor: The small sample size of each treatment group with high intra-individual variability in clinical scores inherent to MG; Some clinical scores which were very low at baseline and therefore decrease the possibility and probability of detecting an effect; The variability in time of testing and also in last acetylcholinesterase inhibitor (e.g. pyridostigmine) intake (which influences the clinical state of the patient at QMG testing).
There was no significant correlation between the change from baseline in clinical scores and the immunogenic response (i.e. B-peptide and T-peptide Abs).
WP5 Phase 2 clinical trial
Task 5.a: Protocol development and submissions
The study CV-0003 (phase 2) was designed and the protocol, informed consent document (ICD) and associated documents developed and the clinical trial application (CTA) was submitted to Belgian and Dutch competent authorities (CA) and to the respective Ethics Committees (EC) (UZA for Belgium, LUMC for Netherlands). The study was accepted in Belgium but the CTA was withdrawn from the Netherlands by Curavac due to the absence of a decision by the LUMC Ethics Committee within the regulatory timeframe. Since the clinical trial could not be performed at LUMC, the consortium did not initiate the recruitment at UZA because the Belgian site was expected to recruit approximately 10% of the patients needed to complete the study. Due to these circumstances it was concluded that it would be very difficult to complete the study within the timeframe of the current project and the project was amended to generate additional in-vitro and in-vivo non-clinical immunogenicity and efficacy data (WP7). A notification to withdraw the Clinical Trial Application in Belgium was sent to both the Competent Authorities and UZA Ethics Committee on the 1st of June 2018.
Task 5.b: Recruitment and study/site set-up
No subject was screened or included.
Task 5.c: Patients vaccination and follow-up
No subject was vaccinated for the CV-0003 study.
Task 5.d: Long-term extension study
The phase 2/3 study was not performed and therefore there was no long-term extension.
Task 5.e (M56 – M58): Data analysis and clinical study report writing
The phase 2/3 study was not performed and therefore there was no long-term extension.
WP6 Product development, dissemination and exploitation plans
Task 6.a: Corporate tools for MYASTERIX external communication
The visual identity of the project was created and includes a logo, a project website, brochure and a powerpoint template. The public part of the website www.myasterix.eu was set up in 4 languages: English, French, Dutch and German (the languages of the partners) and was regularly updated. 10,227 users viewed the website during the project. The top three user countries were France, the United States and the Netherlands.
A brochure in English presenting the general outlines of the project and its participants was prepared and was distributed widely. The pdf version of the brochure is also downloadable from the MYASTERIX public website.
Press releases were launched throughout the project and can be viewed on the website. In particular, a press release was widely disseminated on the formal start of the phase 1b clinical trial in January 2016. The press release was for instance quoted in the Rhumatos journal La pratique quotidienne en rhumathologie which is read in French hospitals.
A poster for the BIO2014 and BIO2015 congresses was prepared and presented at BIO2014, BIO2015, BIO2016, and BIO2017.
In 2017, a twitter account was created @Myasterix1 and was regularly updated. Myasterix has 68 followers and follows 118 organisations or individuals. Myasterix published 28 tweets in 2017 and 2018.
Task 6.b: Market analysis
The objectives of the study were to know if we could understand if and how patients progress between medications and if we could identify subgroups of patients that are poorly managed on the existing standard of care and hence, bear a large proportion of the costs for insurance and healthcare systems. The main findings and conclusions of the study provided a better understanding of the disease’s socio-economic burden.
Task 6.c: Communication with regulators and patients’ associations
Patients’ associations
The consortium had several interactions with patients’ associations throughout the project
CuraVac (Stéphane Huberty and Nicolas Havelange) was invited to present the Myasterix project at the GRAMY (“Groupe de Réflexion Myasthénie”), organised by the AFM (Association française pour les myopathies), in Paris on the 12th of November 2015 in front of researchers, clinicians and patient associations representatives. Marc de Baets (Myasterix Independent Advisory Board) attended the meeting also.
The consortium – CuraVac with the help of Independent Advisory Board members and UZA – communicated actively with the French patients’ organisation, Les A.M.I.S the Belgian Liga-MG and the Dutch Spierziekten Nederland. Two webinars were organised with the help of these organisations to explain the clinical trial to French, Belgian and Dutch patients and small movies were published on YouTube to explain the mechanism of action of the CV-MG vaccine:
16 April 2016 in French: https://www.youtube.com/watch?v=bVUrkHPa8iY
1June 2016 in Dutch https://www.youtube.com/watch?v=xbuYXqmcDYE
These seminars proved to have greatly facilitated the recruitment for the phase 1b trial at UZA.
In addition, CuraVac was in regular contact with the New Jersey and Alabama patients’ organisations and presented the project in front of these organisations in January 2015.
Another meeting took place just before the annual meeting in Paris in September 2016 between CuraVac and the A.M.I.S. vice-president and some patients interested in the trial.
Regulators
CuraVac had interactions with both the European Medicines Agency and with the US Food and Drug Administration. The advice received has been very useful to adapt and validate the clinical development plan of CV-MG. While writing the briefing documents represented a large amount of work, the output is very valuable during discussions with pharmaceutical companies.
CuraVac decided to go for a first protocol assistance (scientific advice meeting for orphan drugs) at the European Medicines Agency in 2015. The pre-submission meeting took place by phone conference with the EMA, GFA and CuraVac on the 11th of June 2015. The final report from EMA was received on the 28th of October 2015. CuraVac then went through a second protocol assistance procedure with EMA. The regulatory strategy was finalized and CuraVac applied for PRIME status at the EMA for the CV-MG01. The submission date for the final briefing document for the follow-up protocol assistance at the EMA was on the 29th of March 2017. The final answer from the EMA was received on the 29th of June 2017.
A pre-IND meeting with the FDA took place on the 27th of July 2017 via teleconference. A pre-IND meeting report was received from the FDA on the 25th of August 2017. In summary, the FDA asked CuraVac to replace the primary endpoint of the phase 2/3, initially “change from baseline in the QMG score” by a responder analysis on the MG-ADL. The FDA therefore wants to replace a physician reported outcome with a patient reported outcome.
Task 6.d: Scientific communication
The consortium members attended several scientific conferences to present the clinical trial, the intermediate and the final results.
A poster on the first results of the tetanus trial was presented in Oxford at the MGTX meeting on the 8th of January 2016 by the LUMC team.
The MG-QoL, one of the outcome measures, was validated for the Dutch language. A scientific article was published.
Professor Mercelis (UZA) was invited to present the Myasterix phase 1b clinical trial at the 13th International Conference on Myasthenia Gravis and Related Disorders held every 5 years by the New York Academy of Science (NYAS) as a Plenary Speaker on 16th May 2017. Prof. Mercelis (UZA) presented the interim results of the phase 1b. The presentation has subsequently been made available on the Myasterix website, Twitter and Facebook accounts.
Ellen Strijbos (LUMC) also presented the data from the tetanus study at this congress in the form of a poster. LUMC produced two scientific articles that were published in international peer-reviewed journals.
Nicolas Havelange at the BIOVISION congress, June 2014.
Task 6.e: Business development
In order to raise maximum visibility for MYASTERIX from potential investors and patient communities, CuraVac participated in two contests: the BioVision Catalyser where MYASTERIX was elected by a panel of independent experts as the most innovative project in the “Immunotherapies and Vaccines” section and the European Venture Contest where CuraVac received the best presentation award from a jury of investors.
Some business angels also invested or reinvested in CuraVac and, although it is uneasy to verify, it is likely that the awards obtained played a role in these new or renewed confidence placed in the project by these investors and in the visibility towards Asian companies.
CuraVac was very active in business development and participated in BIOVISION 2014 (Lyon, BIO2014 (San Diego), BIO2015 (Philadelphia), BIO2016 (San Francisco), BIO2017 (Boston), BIO2018 (Boston) and Bio-Europe 2014 (Frankfurt), 2015 (Munich), 2016 (Köln). CuraVac participated in the BIO congress in June 2017 in San Diego and met with several companies. During each congress, 20 to 30 pre-organized meetings were held. Some companies are still evaluating the technology and the clinical trial results.
The business development strategy pursued is to grant geographically limited licenses to obtain funds allowing securing and accelerating the clinical developments in Europe and possibly in the USA.
CuraVac was in contact with several companies for an early license agreement on the therapy for a limited territory. Nicolas Havelange (CuraVac) travelled to Korea in April 2015 to meet some Korean companies potentially interested in the CV-MG01 for licensing in the region. CuraVac is in contact with several companies for an early license agreement on the therapy but most of the companies decided to wait until the phase 1b results were available. The final results of the phase 1b were communicated and contacts are ongoing with investors and pharmaceutical companies for the next stages of the CV-MG development.
A formal press release on the results of the phase 1b clinical trial was edited and published in September 2018.
WP7 Additional non-clinical studies
Task 7.1 Additional non-clinical studies:
1) Selection of a more potent adjuvant
SEPPIC adjuvants Montanide ISA51VG and Montanide ISA720VG were selected. With SEPPIC, we investigated the compatibility of the new antigen formulation and their adjuvants. The main conclusion of this study is that the buffer has no negative impact on the vaccine formulation up to 24 hours. With these results, it was possible to plan the animal experiments to study the effect of the dose, the number of injections and the adjuvant.
2) Immunogenicity study in healthy rats
The new formulation (CV-MG02) of the vaccine with more peptide B as developed in WP2, the selected SEPPIC adjuvants and more administrations was tested for immunogenicity in healthy rats and compared to the previous formulation with Alhydrogel as adjuvant.
The study started in July 2018. The rats were injected up to 6 times and the different groups compared the adjuvants (ISA51, ISA720 and Alhydrogel) and two doses of the peptides (20µg and 60µg of each peptide).
Immunogenicity was analysed with an ELISA for antibodies to the B and the T peptides.
The main conclusions are that the SEPPIC adjuvants (ISA51 and ISA720) give higher immunogenicity than Alhydrogel (in a range of 2 to 4-fold depending on the groups). For the Alhydrogel, a plateau is reach and increasing the number of injections from 4 to 6 does not lead to higher antibody levels at the selected antigen doses. Both adjuvants from SEPPIC give relatively similar results and the antibody response to the T peptide is lower than to the B peptide (as it has been consistently observed with similar doses in other animal studies).
This study confirms that the best option to obtain a higher immune response is to use a more potent adjuvant (water in oil) and not to increase the number of injections. In humans, an increased dose of B-peptide makes also sense since the immunogenicity is lower than in animals.
3) EAMG study in rats
The missing piece of information for the clinical development of CV-MG is the protective threshold of anti-peptide antibodies. In the previous non-clinical studies (at the University of Alabama), the level of anti-peptide antibodies was never assayed and a correlation between the clinical effect/efficacy and the concentration of anti-peptide antibodies was never established.
This piece of information, often requested by pharmaceutical companies with which CuraVac had discussions, will be very useful for the next stages of the clinical development of the therapy. It will enable the development of a smart clinical protocol, where we could decide to immunize the patients until a certain response is measured (with some limits given by the toxicity study).
For the second objective of this WP7 (to find a “protective” level of anti-peptide antibodies), it is necessary to use the Experimental Autoimmune MG model (EAMG). We wanted to reproduce the model in GLP-like conditions and find a suitable CRO for that purpose. The CER was selected.
The EAMG experiment started in July 2018. It involved immunising healthy rats with high amounts of the vaccine to mount a high antibody concentration and to passively transfer the sera from these animals at different concentrations in other rats in which the disease would be induced by the purified torpedo extract or a recombinant AChR. Protection against the disease should be a function of the amount of antibodies passively transferred.
For the induction of hyperimmune sera, 6 animals were immunized with the B peptide alone, 6 with the T-peptide alone and 6 with the mixture of B and T peptides. Surprisingly, we observed a synergistic effect when injecting the animals with both peptides because there was no antibody response to the T-peptide alone while there was a clear response when the rats were immunized with both peptides together.
Healthy animals were then injected with the purified Torpedo extract and with the recombinant AChR.
This experiment has not been finalised during the duration of the Myasterix project.
WP1 Management & Coordination
The management of the project was under the responsibility of Inserm Transfert as administrative coordinator and CuraVac as scientific coordinator.
Inserm Transfert was responsible for organizing the project meetings (General meetings and Executive Committee meetings). The Kick-off and 5 General meetings were organized. 18 ExCom meetings were organized. 4 periodic reports were submitted and the payments following the approval of the EC were made to the consortium. 4 Amendments to the original Grant Agreement were made.
Inserm Transfert also managed internal communication: all project documents were uploaded to the project intranet; internal newsletters were prepared on a regular basis and were shared with the consortium.
Potential Impact:
Myasterix planned to achieve an impact on five levels. Below, we have described how Myasterix contributed to the expected impact:
1. on MG patients through the availability of a more targeted therapeutic approach with fewer and less severe side effects;
Since the phase 1b was not designed neither powered to assess efficacy and the immunogenic response was not high enough to induce a significant improvement of Myasthenia Gravis, as assessed by clinical scales, there is currently no impact on the population of patients and on society costs and further clinical trials with an optimized more potent vaccine are needed. However, the safety profile is excellent, and some patients were improved at the end of the study. Additionally, an excellent collaboration was established with the clinical centre (UZA) which demonstrated an extensive expertise in Myasthenia Gravis and a good access to patients. This might be helpful for potential future trials.
The licensing discussions with some companies, notably from South Korea and Japan is likely to allow a faster availability to some patients in parts of the world compared to a situation where only approval in Europe and a stand-alone strategy would have been developed.
2. on innovation and competitiveness as the approach can be used in other autoimmune diseases);
CuraVac, as part of its business plan, still intends to develop the same therapeutic vaccination strategy (based on complementary peptides) for other autoimmune diseases. The diseases still need to be identified but will be with high unmet needs. If the next investment round of CuraVac is successfully completed, the Myasterix project would have allowed to initiate innovative approached to treat or cure other autoimmune diseases in the future.
3. on the participating SMEs by providing out-licensing opportunities and scope for further clinical development of the MG vaccine as well as opportunities to develop related vaccines);
The main impact is on the participating SME CuraVac. CuraVac participated in many business forums such as BIOVISION, BIO and BIO-Europe conferences to meet with pharmaceutical and biotechnology companies. Many licensing discussions took place with different companies and, although no firm licence has been signed yet, it was necessary to “prime” the discussions with these companies. It is expected that one or several of the ongoing discussions will lead to the signature of a collaboration agreement with a larger company and allow the faster development of the CV-MG therapy in different parts of the world.
During the project, Aepodia could develop its expertise in therapeutic vaccines and immunology, and reinforce its knowledge of neurology and gain expertise in myasthenia gravis.
piCHEM further strengthened its position as leader of complex peptide manufacturer and gained additional knowledge in peptide-protein conjugation. During the course of the project, piCHEM moved to larger facilities with additional laboratories and GMP production rooms and the Myasterix project was one amongst many other to contribute to this growth in the piCHEM’s activities.
4. on reducing the cost of MG therapy and the treatment of autoimmune diseases generally; and
This is not yet achieved but will be the case if the therapy is successfully brought to the market. Our market analysis has shown that the current cost of MG patients is very high and, if the CV-MG is efficacious and approved, it could lead to a tremendous reduction of the cost of MG for society.
5. on society by reducing the disease burden of MG on health systems around the world.
If and when the therapy is approved, it would have a tremendous impact on the economic burden as well. Our market analysis has shown that MG is a very expensive disease for the health care systems.
The main dissemination activities in the project were as described below.
- Preparation of a project brochure: A brochure in English presenting the general outlines of the project and its participants was prepared and was distributed widely. The pdf version of the brochure is also downloadable from the MYASTERIX public website reaching over 10,000 users. At mid-term, the brochure was modified and updated.
- Development of a project website www.myasterix.eu was set up in 4 languages: English, French, Dutch and German (the languages of the partners) and was regularly updated.
- Press releases were launched throughout the project and can be viewed on the website. In particular, a press release was widely disseminated on the formal start of the phase 1b clinical trial in January 2016. The press release was for instance quoted in the Rhumatos journal La pratique quotidienne en rhumathologie which is read in French hospitals.
- A twitter account was created @Myasterix1 and was regularly updated. Myasterix has 68 followers and follows 118 organisations or individuals. Myasterix published 28 tweets in 2017 and 2018.
- A poster for the BIO2014 and BIO2015 congresses was prepared and presented at BIO2014, BIO2015, BIO2016, and BIO2017.
- Scientific conferences to present the clinical trial, the intermediate and the final results:
o A poster on the first results of the tetanus trial was presented in Oxford at the MGTX meeting on the 8th of January 2016 by the LUMC team.
o Professor Mercelis (UZA) was invited to present the Myasterix phase 1b clinical trial at the 13th International Conference on Myasthenia Gravis and Related Disorders held every 5 years by the New York Academy of Science (NYAS) as a Plenary Speaker on 16th May 2017. Prof. Mercelis (UZA) presented the interim results of the phase 1b. Ellen Strijbos (LUMC) also presented the data from the tetanus study at this congress in the form of a poster.
- 2 publications were written by LUMC.
o Translation and validation of the 15-item Myasthenia Gravis Quality of life scale in Dutch.
o A prospective, placebo controlled study on the humoral immune response to and safety of tetanus revaccination in myasthenia gravis.
- In addition, the consortium had interactions with patient associations: Les A.M.I.S the Belgian Liga-MG and the Dutch Spierziekten Nederland in order to inform patients of the clinical trial and stimulate recruitment interest.
In total, excluding the many business presentations and meetings, 15 oral presentations at a scientific event were made, 4 presentations to a wider public given, 2 posters were presented, 3 press releases circulated, 2 exhibitions, 1 social network account created, 1 conference was organized.
To pave the way for the exploitation of the project results, the following activities were implemented:
- A Market analysis study: The objectives of the study were to know if we could understand if and how patients progress between medications and if we could identify subgroups of patients that are poorly managed on the existing standard of care and hence, bear a large proportion of the costs for insurance and healthcare systems. The main findings and conclusions of the study provided a better understanding of the disease’s socio-economic burden.
- Interactions with regulators: CuraVac had interactions with both the European Medicines Agency and with the US Food and Drug Administration which were useful in the development of the protocol.
- Business development: CuraVac was very active in business development and participated in BIO2015 (Philadelphia), BIO2016 (San Francisco) and Bio-Europe 2015 (Munich). CuraVac participated in the BIO congress in June 2017 in San Diego and met with several companies. During each congress, 20 to 30 meetings were held. CuraVac also participated in BIO2018 congress in Boston. The Biopartnering system was used to select companies with a potential interest in the CV-MG01 product. 23 one-to-one meetings took place and some companies are still evaluating the technology and the clinical trial results. The business development strategy pursued is to grant geographically limited licenses to obtain funds allowing securing and accelerating the clinical developments in Europe and possibly in the USA. CuraVac was in contact with several companies for an early license agreement on the therapy for a limited territory. Nicolas Havelange (CuraVac) travelled to Korea in April 2015 to meet some Korean companies potentially interested in the CV-MG01 for licensing in the region. CuraVac is in contact with several companies for an early license agreement on the therapy but most of the companies decided to wait until the phase 1b results were available. The final results of the phase 1b were communicated and contacts are ongoing with investors and pharmaceutical companies for the next stages of the CV-MG development.
List of Websites:
www.myasterix.eu
Twitter: @Myasterix1
MYASTERIX project aimed to advance a therapeutic vaccine candidate (CV-MG01 with orphan drug status) for the autoimmune disease Myasthenia Gravis (MG) to human proof-of-concept studies. The final goal is to provide a more targeted therapeutic approach with fewer and less severe side effects than the existing therapeutics.
The project was initially divided into 6 main Work Packages, WP1 management, WP2 production, WP3 toxicity study, WP4 phase 1B clinical trial, WP5, phase 2B clinical trial, WP6 exploitation and dissemination.
During the last amendment, the WP7 Additional non-clinical studies, was added.
The WP2, WP3, WP4 were successfully delivered. The WP5 could not be delivered on time and was replaced by the WP7. The WP6 was mainly delivered.
During the course of the project, the consortium was able to manufacture the peptides, the conjugates and the vaccine components (antigen and adjuvant) and demonstrate their stability over three years (WP2). Some unforeseen solubility issues have been solved during the project leading to a more consistent production process.
The GLP regulatory toxicity studies were successfully done on time (WP3).
The very good safety profile of the therapy was documented as part of the phase 1b clinical trial on 24 myasthenic patients (WP4). The recruitment lasted one year in one centre, which represents record high recruitment rates for such a disease. Although lower than expected, immunogenicity to the vaccine components was achieved.
The study design and other factors did not allow drawing any efficacy conclusions on the therapy: meaning that no proof of efficacy could be documented as part of this phase 1b study.
The second clinical study, which should have been a confirmatory trial (WP5) could not take place due to the lack of on-time approval by the ethics committee of the partner that should have carried out the main part of the clinical trial although it was approved by the Belgian regulatory authorities and the UZA Ethics Committee.
Most of the tasks for exploitation and dissemination were successfully delivered: the market study, the communication tools, the contacts with the regulatory authorities (EMA) and the patients’ association and the scientific communications.
For the exploitation part, a term sheet with potential investors is still being negotiated.
In conclusion, the Myasterix project advanced a therapeutic vaccine candidate to first-in-human studies and showed its excellent safety profile. This project allowed opening the way to a proof of concept of this therapy and the future developments.
Project Context and Objectives:
Concept:
The concept developed in this 5-year SME-led project was to advance a therapeutic vaccine candidate (CV-MG01 with orphan drug status) for the autoimmune disease myasthenia gravis (MG) to human proof-of-concept studies.
The objectives were defined as follows:
(1) to manufacture according to the appropriate guidelines, batches of the candidate vaccine for toxicology and clinical studies,
(2) to carry out preclinical toxicity testing of the product following Good Laboratory Practice guidelines and initiate stability testing;
(3) to gain approval for and perform a phase I clinical trial during the third and fourth years to demonstrate safety, tolerability and immunogenicity of the MG therapeutic vaccine candidate
(4) to gain approval for and perform a phase II clinical trial during the fourth and fifth years of the project to demonstrate efficacy and achieve proof of concept of the proposed therapy. In case the phase II trial could not be performed, the goal was to replace it by accumulating proof of mechanism of action data in vitro (with the biological material generated during the phase 1 study) and in vivo on animal models.
Myasthenia gravis
Myasthenia gravis (MG) is a neuromuscular disorder in which functional acetylcholine receptors (AChR) become depleted at neuromuscular junctions due to an antibody-mediated autoimmune attack on the neuromuscular synapse. AChR antibodies can be detected in the serum of ~90% of patients with generalised MG. It is a rare orphan disease with a prevalence of 1.6–2 per 10,000 people and an incidence of 1.2–1.5 per 100,000 people in the EU.
Current treatments include symptomatic pharmacotherapy, immunosuppressive medication, immunomodulating therapies and a surgical procedure (thymectomy). Symptomatic pharmacotherapy using acetylcholinesterase inhibitors increases the availability of acetylcholine (ACh) at the neuromuscular junctions. Immunosuppressive medications include prednisone, cyclosporine, azathioprine, mycophenolate mofetil and occasionally cyclophosphamide. Immunomodulating approaches include plasmapheresis and the use of intravenous immunoglobulin (IVIg).
The pathogenesis of MG can be attributed predominantly to IgG antibodies against the α-chain of the nicotinic AChR, often targeting residues 61-76, which is known as the main immunogenic region (MIR) (Weathington et al., 2003). The T-cell dependency of pathogenic anti-MIR antibodies is supported by: (1) the IgG isotype of anti-AChR antibodies (with an isotype switch from IgM to IgG); (2) the relative benefit of thymectomy; and the ability of antibodies against (3) cluster of differentiation 4 (CD4) and (4) major histocompatibility complex (MHC) class II, to improve experimental autoimmune myasthenia gravis (EAMG) in rats.
Given the central role of autoantibodies in MG pathogenesis, targeted reduction of specific anti-MIR antibodies should considerably improve or even normalise the functionality of the neuromuscular junction in MG patients.
Proposed therapeutic vaccine
The vaccine candidate comprises two synthetic peptides. RhCA 67-16 is designed to generate antibodies (anti-idiotypic Abs) that bind autoantibodies (idiotypic antibodies, Id Abs) and RhCA 611-001 is designed to generate antibodies that bind T-cell receptors (TCRs). Each peptide is separately coupled to CRM197, a genetically detoxified diphtheria toxoid (DT) carrier. The conjugated peptides are mixed with a saline solvent and adsorbed to the alum adjuvant.
Mechanism of action
The proposed treatment follows the molecular logic of antigen receptor mimetic (ARM) vaccination for autoimmune diseases reviewed by Weathington and Blalock (2003). For MG, the autoimmune assault on the nicotinic AChRs of skeletal muscles often causes a severe deficit in muscle function due to the destruction of muscular tissue architecture at the neuromuscular junction. The main B-cell epitope on the AChR (MIR, see above) is probably targeted by molecular mimicry, leading to the loss of self-tolerance for the nicotinic AChR and the generation of Id Abs. T-cell sensitisation to a T-cell epitope on the nicotinic AChR (α-subunit residues 100-116) is thought to promote cytokine-mediated B-cell isotype switching and the production of circulating anti-AChR IgG antibodies (detectable in ~90% of MG patients). By vaccinating with the ARM vaccines for each epitope, we aim to generate antibody responses that react against the pathogenic Id Abs (anti-idiotypic Abs) and to the TCR for T-cell clones reactive to nicotinic AChR (anti-TCR Abs), thus reducing pathogenic anti-MIR antibody responses and restoring function at the neuromuscular junction.
The Abs reactive with the B epitope are reactive to the B cell Ag receptor and bind and annihilate circulating Abs (Araga et al., 1993, 1996 see summary hereunder) while the Abs reactive with the T cell Ag receptor seems to inhibit T cell proliferation and induce regulatory T cells (TREG). The administration of monoclonal Ab (mAb) derived from vaccinated animals and reactive with Vb15+ TCR specific for AChR 100-116 has been shown in vitro to block proliferation of target T cells while also changing cytokine profile, decreasing IFNγ, increasing IL-10 and increasing the percentage of CD4+ CD25 T cells pointing to the action of TREG (Xu et al., 2001).
Why the proposed vaccine should work in MG patients
Myasthenia gravis is a T-cell dependent, B-cell mediated autoimmune disease and therefore both T-cell and B-cell epitopes responsible for anti-MIR antibodies were to be targeted using a combined therapeutic vaccine based on the complementary RhCA 67-16 and RhCA 611-001 peptides.
Treatment with the proposed therapeutic vaccine specifically targets the underlying immune disorder in the EAMG rat model and in the spontaneous MG canine model. The vaccine candidate therefore has the potential to preserve immune system function in MG patients while treating the underlying pathology.
Objectives:
Production of preclinical and clinical GMP batches
Existing SOPs for the manufacture of the human formulation of CV-MG01 were used to produce a preclinical GMP-like batch which has been tested for immunogenicity in healthy rats. It was planned that technology transfer from CuraVac to piCHEM would be implemented, followed by the manufacture of batches for toxicology studies and clinical trials. Stability studies would then be carried out according to the International Conference on Harmonisation (ICH) guidelines on the drug substance and the drug product, on three batches (preclinical, phase I and phase II).
Preclinical toxicity study
A GLP toxicology programme consistent with CPMP/ICH/286/95 and CPMP/SWP/465/95 was planned to be carried out using 40 rats which would receive the highest planned human dose (not per weight ratio) injected four times (one time more that the planned human schedule) using the schedule that yields the best immunisation in rats (15-day intervals between injections). Half of the rats were to be sacrificed the day after the last immunisation and the other half 15 days later for toxicity assessment. Complete necropsy and anatomopathology would then be performed.
Phase I clinical trial
A complete clinical trial application (CTA) compiling the investigational medicinal product dossier (IMPD), the investigator brochure (IB) and the other necessary documents was planned to be submitted to the Dutch ethical and competent authorities. After a refusal by these, a contingency procedure was activated. A new University Hospital partner was integrated in the Consortium (UZA) and the CTA was successfully submitted to the Belgian competent authority and the Ethics Committee of the Hospital (UZA).
A first-in-human clinical trial was to be carried out in MG patients to assess the safety, tolerability and immunogenic response following subcutaneous injections of CV-MG01. The trial was to be designed as a human pharmacology and therapeutic exploratory, dose escalation, parallel group, randomised, placebo-controlled, multiple treatment, single centre, investigator and subject-blind study using adaptive dose and sample size approaches.
It was planned that each subject would receive three subcutaneous injections at weeks 1, 4 and 12 in a study that lasts 16 weeks per subject. Each subject would receive 18 µg of the B peptide and 60µg of the T peptide for the low dose and 60µg of the B peptide and 200 µg of the T peptide for the high dose, the former corresponding to the peptide dose in the dog trial (500 µg of conjugate, ~20 µg of peptide equivalent) and the latter corresponding to a dose that has been used for peptide vaccines in previous clinical studies to elicit strong immunogenicity (Cytos Biotechnology in hypertension, NicVax in nicotine addiction). The placebo was to be the adjuvant alone (making the blinding feasible as the adjuvant and adjuvanted vaccines are both white colloidal suspensions). The aim was to carry out the trial at UZA (University Hospital Antwerp) with partner 5 (Aepodia) managing protocol development, submissions, site management, statistics, data management, pharmacovigilance, clinical study report (CSR) preparation and quality assurance for good clinical practice (GCP) compliance.
Phase II clinical trial
A phase II proof-of-concept (POC) study was planned in MG patients to assess clinical efficacy following subcutaneous injections of CV-MG01.
The trial was designed as a therapeutic confirmatory, parallel group, randomised, placebo-controlled, multiple treatments, single centre, investigator and subject-blind. The dosing scheme (i.e. three injections) will be the same as that in the first-in-man trial, although potentially could be adjusted depending on the findings. The initial objectives were:
• To evaluate the efficacy of the treatment using the MGC scale and clinical evaluation, and to demonstrate the proof of concept of the vaccine.
• To assess the immunogenic response to CV-MG01 by monitoring RhCA 611-001 and RhCA 67-16 antibodies and the effect on the plasma level of AChR Ab, and to demonstrate the expected mechanism of action of the vaccine.
• To monitor the safety and tolerability of CV-MG01.
As a contingency procedure, in case the phase II clinical trial is not approved on time to be finished during the project allocated time, the phase II clinical trial was planned to be replaced by additional non-clinical studies taking into account the results of the phase I and targeting to accumulate proof of concept data in vitro and in vivo.
Dissemination and exploitation
This EC project aimed to address an important funding gap for early-phase therapeutics, especially in orphan diseases, but several investors and pharmaceutical companies have indicated that once the project has reached human proof-of-concept, they are willing to invest in the project or the company, or to licence-in the vaccine. In the first three years of the project, Myasterix aimed to gain more data to consolidate the corresponding business plan whereas in the last two years, once initial results become available, discussions and negotiations with potential investors would commence. This was to guarantee an immediate transition from public to private investment, which is required to finally reach the market.
The vaccine development plan was to be fine-tuned at this stage by contact with patients’ associations and the regulatory authorities (EMA) to validate the anticipated target product profile and define the number of patients needed in phase III trials (currently estimated to be 120). The target product profile (TPP) would also be adapted throughout the project, based on preliminary clinical trial results.
Better production process knowledge will also allow us to evaluate process validation and market manufacturing costs for the vaccine, and thus verify the cost side of the project business plan (clinical development and manufacturing costs). Detailed market analysis will be carried out to provide a robust evaluation of the market size and product reimbursement price, thus verifying the revenue side of the project business plan.
With these studies and reports, the consortium will have confidence in the product valuation which will facilitate contacts with potential licensors and investors (pharmaceutical and biotechnology companies, or venture capitalists).
Project Results:
The main results of the project are described below per Work package.
WP2 Production
WP2 was organized into 8 tasks. The main results of each task are summarized below.
Task 2.a: Process transfer and small-scale test batches
During the first period of the project, the technology transfer from CuraVac to piCHEM was completed. A revised protocol for the conjugation has been evaluated in order to compare the different methods in a comparative immunogenicity study.
Task 2.b: GMP production of peptide antigens
Peptide antigen T-Peptide has been synthesized in R&D-grade and GMP-grade quality at large scale, whereas B-Peptide was synthesized at GMP-grade quality in large scale. For the production of the corresponding conjugates for the toxicity study T-Peptide in R&D-grade and B-Peptide in GMP-grade quality were used.
All synthesized batches were released by piCHEM’s Quality Control (R&D-grade peptide) and Qualified Person (GMP-grade peptides) according to their specifications. CuraVac approved the specifications of the peptide antigens. As sponsor of the clinical trial, CuraVac audited piCHEM for GMP compliance.
Task 2.c: Production and quality control of toxicity batches
For the production of the vaccine for the toxicity study two conjugates (T-Peptide-CRM and B-Peptide-CRM) have been produced and released according to the previous designed method (task 2.a.). Carrier Protein CRM197 has been activated by the heterobifunctional cross-linker GMBS to present a linkage group between the protein and the antigenic peptides. Both, unreacted GMBS and unreacted peptides have been removed by several ultrafiltration and centrifugation steps. The two conjugates (drug substance) have been formulated as lyophilisate without any buffer salts. Swiss company Baccinex was subcontracted for the final fill and finish process of the vaccine (drug product).
The vaccine was designed as a two-component kit:
• Component 1: CV-MG01 Antigen; consists of the mixed conjugate (T-Peptide-CRM and B-Peptide-CRM) freeze dried together with Mannitol
• Component 2: CV-MG01 Adjuvant; consists of Alhydrogel suspended in NaCl solution
Both components were analysed and released by the QC unit of piCHEM.
Task 2.d: Production of the phase I GMP drug substance batch
It was decided that the GMP drug substance batch should be produced and formulated identical to the toxicity batch as a two-component kit: CV-MG01 Antigen and CV-MG01 Adjuvant.
For the clinical phase I study the starting material (carrier protein CRM197 and the two peptides T-Peptide and B-Peptide) were used in GMP-grade quality. The conjugates were produced by piCHEM and both drug substances were shipped to Baccinex for the final fill & finish at the end of Nov 2014.
Task 2.e: Final formulation GMP vaccine for clinical phase 1
Final formulation of the GMP vaccine for the clinical phase I study was subcontracted to the company Baccinex. Some challenges were encountered with filtration and the operation had to be repeated on a second batch with separate filtration of the B-peptide and T-peptide conjugates.
Task 2.f: Stability study of GMP drug product batch for clinical phase I
All QC released intermediates and final products were subjected to stability studies at different temperatures and different durations. piCHEM performed all the stability studies. The stability protocol was checked and agreed by CuraVac.
In the final period of the project, the stability studies were finalized and additional non-GMP batches of the conjugates were manufactured to support the non-clinical studies. The compatibility of more potent adjuvants with the new formulation was tested.
The stability studies enabled the shelf-life extension of the product used in the clinical trial at UZA. The antigen and the adjuvant vials now have a proven stability of three years.
Task 2.g: Production of the phase II GMP drug substance batches
In February 2016 it was decided to start the production of both the B-Peptide and the T-Peptide in GMP-grade quality. These peptides served as starting material for the production of R&D-grade conjugates (B-Peptide-CRM, T-Peptide-CRM) for further solubility and formulation studies.
Both peptides could also have served as starting material for the production of phase II GMP drug substance batches in case of need, but the priority was focused on solving the low solubility of the conjugates with the current formulation.
The production of both peptides was performed by piCHEM; the B-Peptide was released on 27th of July 2016, whereas the T-Peptide was released on 30th of August 2016.
Besides these considerations, it was also decided that the drug substance and product for the clinical phase II could be the same as the ones for the phase I thanks to the good stability data obtained on the products and thanks to the sufficient number of vials (see also task 2.h here under).
Task 2.h: Final formulation GMP vaccine for clinical phase II
No final formulation of the GMP vaccine for phase II was needed.
It was decided to use the left-over vials from the production of the GMP vaccine (CV-MG01 Anti-gen BatchNo AB8-150504 and CV-MG01 Adjuvant BatchNo AB9-141102) manufactured for the clinical phase I also for clinical phase II (which did not take place in the end)
Task 2.i: Stability study of GMP drug product batch for clinical phase II
It was decided that GMP drug product batch produced for clinical phase I would also be used also for clinical phase II, so no new stability study was required. However, data from the stability study of the GMP drug product batch for clinical phase I was to be used. Phase II did not take place.
WP3 Toxicity study
To conduct the toxicity study, the consortium referred to the WHO guidelines for vaccines and adjuvants “Guidelines on the nonclinical evaluation of vaccine adjuvants and adjuvanted vaccines” from October 2013 which was not available at the time the proposal was written.
The toxicology was performed at an Association for Assessment and Accreditation of Laboratory Animal Care (AAALAC) facility with the toxicology batch supplied by piCHEM. Immunogenicity tests showed that the vaccine components generated their intended pharmacological action in the animals.
No adverse events were reported during the in-life phase and no differences were reported between the control group and the groups that received the vaccine or the components in terms of systemic toxicity. After full necropsy, no general adverse findings were reported.
The conclusions of the toxicity report were also used in the Clinical Trial Application for Phase I.
Task 3.a: Final CRO selection
Several CROs were contacted for the toxicity study and CiToxLAB was selected.
Task 3.b: Protocol writing and approval
The in vivo phase protocol was developed on the basis of the new WHO guidelines. Careful consideration was given to the choice of animals. Rats were an obvious choice for the project because many pre-clinical studies assessing the efficacy (the EAMG model) but also the immunogenicity studies of the vaccine were done on rats. The immunological detection tools (ELISA) were also already developed for rat sera. The number of animals was set at 30 per group according to the new guidelines and the number of groups was limited to three because we use the well-known adjuvant aluminium hydroxide which is used in numerous approved vaccines.
The protocol was approved early August 2014.
Task 3.c: Study in-life phase
The in-life phase was managed as planned in the protocol with the first injection on the 11th of August 2014 and the last sacrifice on the 10th of October 2014.
Task 3.d: Final report writing
The final QA approved report was sent by CiToxLAB in April 2015 and was made available to the regulatory authorities.
WP4 Phase 1b clinical trial
Task 4.a: Protocol development and submissions
The first Clinical Trial Application (CTA) prepared by CuraVac, Aepodia, LUMC and piCHEM was presented to the Dutch competent authorities and was refused in July 2015 after an appeal by the Sponsor representing the Consortium.
As a contingency plan, it was decided to include a new University Hospital partner in the Consortium to submit a slightly revised protocol to the Belgian competent authority and UZA, as new Partner, Ethics Committee.
The second Clinical Trial Application (CTA) prepared by CuraVac, UZA, Aepodia, LUMC and piCHEM was accepted in October 2015 by the Belgian competent authority and by the UZA Ethics Committee.The study protocol CV-0002 (phase 1b), EudraCT 2015-002880-41, entitled “A first-in-human and proof-of-concept study” to assess the safety, tolerability and immunogenic response after subcutaneous injections of CV-MG01, acetylcholine receptor mimetic peptides, as potential therapeutic vaccine, in patients with myasthenia gravis was developed and designed to assess the following objectives:
- Primary objectives: To evaluate the safety and tolerability of CV-MG01 after subcutaneous injections in patients with MG and to assess the immunogenic response after subcutaneous injections of CV-MG01 on the plasma levels of B- and T- peptide antibodies.
- Secondary objectives: To assess the effect of CV-MG01 subcutaneous injections on the plasma level of acetylcholine receptors antibodies (AChR Abs) and to perform a preliminary evaluation of efficacy using clinical scales and questionnaires.
- Exploratory objectives: To explore changes in the humoral and cellular immune responses.
The study was divided into 2 parts: Part A (dosing phase) and Part B (safety follow-up phase).
It was necessary to amend the protocol at various stages of the study throughout the project. The Protocol that was originally accepted by the Belgian Competent Authority and the UZA Ethics Committee was protocol version 5. The protocol version 8 (latest version, substantial amendment) was approved by the Belgian Competent Authority and the UZA ethics committee (EC) on 29 and 20 August 2018 respectively.
Task 4.b: Recruitment and study/site set-up
A pilot study using tetanus vaccinations has been set up at LUMC. CME approval for this study was obtained and patients were recruited. The aim was to include 50 AChR MG patients and test the response to a boost with tetanus vaccine. The AChR antibody titers and the T-cell and B-cell responses were tested using the same protocol as for the phase 1b clinical trial using the CV-MG vaccine. The results of the tetanus study were published.
As soon as the consortium obtained Belgian regulatory approvals, part A of phase I clinical trial started at UZA at the beginning of November 2015. The study has been conducted at UZA hospital (Antwerp, Belgium) under the supervision of Prof. Rudy Mercelis as Principal Investigator.
The first patient entered the study on the 3rd of February 2016 with a first dose on the 30th of March 2016.
By September 2016, cohorts 1 and 2 of the CV-002 study were fully recruited (16 patients included from more than 25 patients screened). No serious adverse event was reported. 8 patients were recruited for the 3rd cohort.
In total, 25 patients were recruited in 13 months in one centre which represents a very high rate for a disease like MG. It shows the interest and expectations from the patients for a better therapy than the existing treatments.
Task 4.c: Patient vaccinations and follow-up
On the 12th of August 2016, the Interim Data Review 1 was organized (after visit 4 of the first 6 patients of cohort 1). The low dose of CV-MG01 was firstly tested on a first cohort. This low dose was deemed safe and the Data Review Committee agreed to start the injections using the high dose. The first patient of cohort 2 was injected on the 17th of August a few days after this decision.
Blinded analysis of the first set of available sera from the first cohort of MG patients showed that several patients produced antibodies to either the B-cell or T-cell peptide or both.
A second Interim Data Review meeting was organized in December 2016 to decide which dose level (high or low) will be tested in cohort 3. The first dosing (with the high dose) of this third cohort was scheduled on the 10th of January 2017.
At UZA, a total of 24 patients completed the study Part A with a last patient visit on 13 September 2017 and received the 3 subcutaneous injections (8 patients for each cohort): 6 received the low dose, 12 the high dose and 6 the placebo.
Immunogenicity (antibodies against B- and T-peptides) and safety were assessed as primary endpoints. Secondary endpoints included AChR antibody titre changes and assessment of efficacy using clinical scales and questionnaires.
The database lock for Part A (clinical and safety data) was performed on the 1st December 2017. The CV-MG01 vaccine was well tolerated and no serious adverse event occurred during study Part A.
Data revealed that some patients showed immunoreactivity against the B and T peptide. The titres rose after the first vaccination and continued to increase after the second.
The AChR titers remained stable over time for all patients. CRM197 reactivity clearly confirmed the vaccination as the titres increased throughout the study after the vaccinations.
Overall, the immunogenic response was found to be much lower compared to what was expected from animal studies.
The final results of part A confirm the excellent safety profile of the vaccine. The immunogenicity is relatively low and no conclusion on efficacy can be drawn from this first study.
Task 4.d: Long-term extension study
The first visit of part B took place on 16th of December 2016. The total duration of Part B was reduced from its original duration of two years to fit with the project timelines. All 24 patients who completed the 10 visits of study Part A had accepted to participate in the safety follow-up part of the study (Part B), the long-term extension study.
In total, all patients completed Visit 11 (4-month follow-up); 23 patients completed Visit 12 (8-month follow-up); 21 patients completed Visit 13 (12-month follow-up); 13 patients completed Visit 14 (16-month follow-up); 8 patients completed Visit 15 (20-month follow-up); 2 patients completed Visit 16 (24-month follow-up).
The safety profile of the vaccine is excellent, and no safety concern has been identified. In Part B, 1 patient reported 3 Serious AEs. These Serious AEs were considered as not related to study drug administration, since the events occurred more than 16 months after the last injection of CV-MG01 (low dose).
Task 4.e: Data analysis and clinical study report writing
The Statistical Analysis Plan v1 was prepared by Aepodia and was approved on 29 November 2017. Analyses of the primary and secondary endpoints were performed after database lock.
The Clinical Study Report of Part A was finalized by Aepodia and was approved by the Principal Investigator and Sponsor on 23 and 24 May 2018 respectively.
The last patient last visit (Part B) was performed on 28 September 2018. The Statistical Analysis Plan v2 (Part B) was prepared by Aepodia and approved on October 2018. The Database lock for Part B will be performed in December 2018 and the Clinical Study Report (Part B) is expected to be released in early 2019.
Patients had on average improved at the end of the study part A. However, no significant difference was observed between treatment groups (i.e. study low dose, study high dose and placebo) in each of the 4 scales used (i.e. QMG, MGC, MG-ADL, MG-QoL15). Moreover, 2-point MG-ADL and 3-point QMG responder rates were not different between treatment groups.
This lack of observed difference in clinical efficacy variables might be explained by 2 main limiting factors:
- Immunogenicity factor: The immunogenicity developed (i.e. generation of anti-peptide Abs following vaccine injection) might be too low to generate a significant blockade in auto-antibodies against ACh Receptor, and therefore to induce a clinical effect.
- Methodological factor: The small sample size of each treatment group with high intra-individual variability in clinical scores inherent to MG; Some clinical scores which were very low at baseline and therefore decrease the possibility and probability of detecting an effect; The variability in time of testing and also in last acetylcholinesterase inhibitor (e.g. pyridostigmine) intake (which influences the clinical state of the patient at QMG testing).
There was no significant correlation between the change from baseline in clinical scores and the immunogenic response (i.e. B-peptide and T-peptide Abs).
WP5 Phase 2 clinical trial
Task 5.a: Protocol development and submissions
The study CV-0003 (phase 2) was designed and the protocol, informed consent document (ICD) and associated documents developed and the clinical trial application (CTA) was submitted to Belgian and Dutch competent authorities (CA) and to the respective Ethics Committees (EC) (UZA for Belgium, LUMC for Netherlands). The study was accepted in Belgium but the CTA was withdrawn from the Netherlands by Curavac due to the absence of a decision by the LUMC Ethics Committee within the regulatory timeframe. Since the clinical trial could not be performed at LUMC, the consortium did not initiate the recruitment at UZA because the Belgian site was expected to recruit approximately 10% of the patients needed to complete the study. Due to these circumstances it was concluded that it would be very difficult to complete the study within the timeframe of the current project and the project was amended to generate additional in-vitro and in-vivo non-clinical immunogenicity and efficacy data (WP7). A notification to withdraw the Clinical Trial Application in Belgium was sent to both the Competent Authorities and UZA Ethics Committee on the 1st of June 2018.
Task 5.b: Recruitment and study/site set-up
No subject was screened or included.
Task 5.c: Patients vaccination and follow-up
No subject was vaccinated for the CV-0003 study.
Task 5.d: Long-term extension study
The phase 2/3 study was not performed and therefore there was no long-term extension.
Task 5.e (M56 – M58): Data analysis and clinical study report writing
The phase 2/3 study was not performed and therefore there was no long-term extension.
WP6 Product development, dissemination and exploitation plans
Task 6.a: Corporate tools for MYASTERIX external communication
The visual identity of the project was created and includes a logo, a project website, brochure and a powerpoint template. The public part of the website www.myasterix.eu was set up in 4 languages: English, French, Dutch and German (the languages of the partners) and was regularly updated. 10,227 users viewed the website during the project. The top three user countries were France, the United States and the Netherlands.
A brochure in English presenting the general outlines of the project and its participants was prepared and was distributed widely. The pdf version of the brochure is also downloadable from the MYASTERIX public website.
Press releases were launched throughout the project and can be viewed on the website. In particular, a press release was widely disseminated on the formal start of the phase 1b clinical trial in January 2016. The press release was for instance quoted in the Rhumatos journal La pratique quotidienne en rhumathologie which is read in French hospitals.
A poster for the BIO2014 and BIO2015 congresses was prepared and presented at BIO2014, BIO2015, BIO2016, and BIO2017.
In 2017, a twitter account was created @Myasterix1 and was regularly updated. Myasterix has 68 followers and follows 118 organisations or individuals. Myasterix published 28 tweets in 2017 and 2018.
Task 6.b: Market analysis
The objectives of the study were to know if we could understand if and how patients progress between medications and if we could identify subgroups of patients that are poorly managed on the existing standard of care and hence, bear a large proportion of the costs for insurance and healthcare systems. The main findings and conclusions of the study provided a better understanding of the disease’s socio-economic burden.
Task 6.c: Communication with regulators and patients’ associations
Patients’ associations
The consortium had several interactions with patients’ associations throughout the project
CuraVac (Stéphane Huberty and Nicolas Havelange) was invited to present the Myasterix project at the GRAMY (“Groupe de Réflexion Myasthénie”), organised by the AFM (Association française pour les myopathies), in Paris on the 12th of November 2015 in front of researchers, clinicians and patient associations representatives. Marc de Baets (Myasterix Independent Advisory Board) attended the meeting also.
The consortium – CuraVac with the help of Independent Advisory Board members and UZA – communicated actively with the French patients’ organisation, Les A.M.I.S the Belgian Liga-MG and the Dutch Spierziekten Nederland. Two webinars were organised with the help of these organisations to explain the clinical trial to French, Belgian and Dutch patients and small movies were published on YouTube to explain the mechanism of action of the CV-MG vaccine:
16 April 2016 in French: https://www.youtube.com/watch?v=bVUrkHPa8iY
1June 2016 in Dutch https://www.youtube.com/watch?v=xbuYXqmcDYE
These seminars proved to have greatly facilitated the recruitment for the phase 1b trial at UZA.
In addition, CuraVac was in regular contact with the New Jersey and Alabama patients’ organisations and presented the project in front of these organisations in January 2015.
Another meeting took place just before the annual meeting in Paris in September 2016 between CuraVac and the A.M.I.S. vice-president and some patients interested in the trial.
Regulators
CuraVac had interactions with both the European Medicines Agency and with the US Food and Drug Administration. The advice received has been very useful to adapt and validate the clinical development plan of CV-MG. While writing the briefing documents represented a large amount of work, the output is very valuable during discussions with pharmaceutical companies.
CuraVac decided to go for a first protocol assistance (scientific advice meeting for orphan drugs) at the European Medicines Agency in 2015. The pre-submission meeting took place by phone conference with the EMA, GFA and CuraVac on the 11th of June 2015. The final report from EMA was received on the 28th of October 2015. CuraVac then went through a second protocol assistance procedure with EMA. The regulatory strategy was finalized and CuraVac applied for PRIME status at the EMA for the CV-MG01. The submission date for the final briefing document for the follow-up protocol assistance at the EMA was on the 29th of March 2017. The final answer from the EMA was received on the 29th of June 2017.
A pre-IND meeting with the FDA took place on the 27th of July 2017 via teleconference. A pre-IND meeting report was received from the FDA on the 25th of August 2017. In summary, the FDA asked CuraVac to replace the primary endpoint of the phase 2/3, initially “change from baseline in the QMG score” by a responder analysis on the MG-ADL. The FDA therefore wants to replace a physician reported outcome with a patient reported outcome.
Task 6.d: Scientific communication
The consortium members attended several scientific conferences to present the clinical trial, the intermediate and the final results.
A poster on the first results of the tetanus trial was presented in Oxford at the MGTX meeting on the 8th of January 2016 by the LUMC team.
The MG-QoL, one of the outcome measures, was validated for the Dutch language. A scientific article was published.
Professor Mercelis (UZA) was invited to present the Myasterix phase 1b clinical trial at the 13th International Conference on Myasthenia Gravis and Related Disorders held every 5 years by the New York Academy of Science (NYAS) as a Plenary Speaker on 16th May 2017. Prof. Mercelis (UZA) presented the interim results of the phase 1b. The presentation has subsequently been made available on the Myasterix website, Twitter and Facebook accounts.
Ellen Strijbos (LUMC) also presented the data from the tetanus study at this congress in the form of a poster. LUMC produced two scientific articles that were published in international peer-reviewed journals.
Nicolas Havelange at the BIOVISION congress, June 2014.
Task 6.e: Business development
In order to raise maximum visibility for MYASTERIX from potential investors and patient communities, CuraVac participated in two contests: the BioVision Catalyser where MYASTERIX was elected by a panel of independent experts as the most innovative project in the “Immunotherapies and Vaccines” section and the European Venture Contest where CuraVac received the best presentation award from a jury of investors.
Some business angels also invested or reinvested in CuraVac and, although it is uneasy to verify, it is likely that the awards obtained played a role in these new or renewed confidence placed in the project by these investors and in the visibility towards Asian companies.
CuraVac was very active in business development and participated in BIOVISION 2014 (Lyon, BIO2014 (San Diego), BIO2015 (Philadelphia), BIO2016 (San Francisco), BIO2017 (Boston), BIO2018 (Boston) and Bio-Europe 2014 (Frankfurt), 2015 (Munich), 2016 (Köln). CuraVac participated in the BIO congress in June 2017 in San Diego and met with several companies. During each congress, 20 to 30 pre-organized meetings were held. Some companies are still evaluating the technology and the clinical trial results.
The business development strategy pursued is to grant geographically limited licenses to obtain funds allowing securing and accelerating the clinical developments in Europe and possibly in the USA.
CuraVac was in contact with several companies for an early license agreement on the therapy for a limited territory. Nicolas Havelange (CuraVac) travelled to Korea in April 2015 to meet some Korean companies potentially interested in the CV-MG01 for licensing in the region. CuraVac is in contact with several companies for an early license agreement on the therapy but most of the companies decided to wait until the phase 1b results were available. The final results of the phase 1b were communicated and contacts are ongoing with investors and pharmaceutical companies for the next stages of the CV-MG development.
A formal press release on the results of the phase 1b clinical trial was edited and published in September 2018.
WP7 Additional non-clinical studies
Task 7.1 Additional non-clinical studies:
1) Selection of a more potent adjuvant
SEPPIC adjuvants Montanide ISA51VG and Montanide ISA720VG were selected. With SEPPIC, we investigated the compatibility of the new antigen formulation and their adjuvants. The main conclusion of this study is that the buffer has no negative impact on the vaccine formulation up to 24 hours. With these results, it was possible to plan the animal experiments to study the effect of the dose, the number of injections and the adjuvant.
2) Immunogenicity study in healthy rats
The new formulation (CV-MG02) of the vaccine with more peptide B as developed in WP2, the selected SEPPIC adjuvants and more administrations was tested for immunogenicity in healthy rats and compared to the previous formulation with Alhydrogel as adjuvant.
The study started in July 2018. The rats were injected up to 6 times and the different groups compared the adjuvants (ISA51, ISA720 and Alhydrogel) and two doses of the peptides (20µg and 60µg of each peptide).
Immunogenicity was analysed with an ELISA for antibodies to the B and the T peptides.
The main conclusions are that the SEPPIC adjuvants (ISA51 and ISA720) give higher immunogenicity than Alhydrogel (in a range of 2 to 4-fold depending on the groups). For the Alhydrogel, a plateau is reach and increasing the number of injections from 4 to 6 does not lead to higher antibody levels at the selected antigen doses. Both adjuvants from SEPPIC give relatively similar results and the antibody response to the T peptide is lower than to the B peptide (as it has been consistently observed with similar doses in other animal studies).
This study confirms that the best option to obtain a higher immune response is to use a more potent adjuvant (water in oil) and not to increase the number of injections. In humans, an increased dose of B-peptide makes also sense since the immunogenicity is lower than in animals.
3) EAMG study in rats
The missing piece of information for the clinical development of CV-MG is the protective threshold of anti-peptide antibodies. In the previous non-clinical studies (at the University of Alabama), the level of anti-peptide antibodies was never assayed and a correlation between the clinical effect/efficacy and the concentration of anti-peptide antibodies was never established.
This piece of information, often requested by pharmaceutical companies with which CuraVac had discussions, will be very useful for the next stages of the clinical development of the therapy. It will enable the development of a smart clinical protocol, where we could decide to immunize the patients until a certain response is measured (with some limits given by the toxicity study).
For the second objective of this WP7 (to find a “protective” level of anti-peptide antibodies), it is necessary to use the Experimental Autoimmune MG model (EAMG). We wanted to reproduce the model in GLP-like conditions and find a suitable CRO for that purpose. The CER was selected.
The EAMG experiment started in July 2018. It involved immunising healthy rats with high amounts of the vaccine to mount a high antibody concentration and to passively transfer the sera from these animals at different concentrations in other rats in which the disease would be induced by the purified torpedo extract or a recombinant AChR. Protection against the disease should be a function of the amount of antibodies passively transferred.
For the induction of hyperimmune sera, 6 animals were immunized with the B peptide alone, 6 with the T-peptide alone and 6 with the mixture of B and T peptides. Surprisingly, we observed a synergistic effect when injecting the animals with both peptides because there was no antibody response to the T-peptide alone while there was a clear response when the rats were immunized with both peptides together.
Healthy animals were then injected with the purified Torpedo extract and with the recombinant AChR.
This experiment has not been finalised during the duration of the Myasterix project.
WP1 Management & Coordination
The management of the project was under the responsibility of Inserm Transfert as administrative coordinator and CuraVac as scientific coordinator.
Inserm Transfert was responsible for organizing the project meetings (General meetings and Executive Committee meetings). The Kick-off and 5 General meetings were organized. 18 ExCom meetings were organized. 4 periodic reports were submitted and the payments following the approval of the EC were made to the consortium. 4 Amendments to the original Grant Agreement were made.
Inserm Transfert also managed internal communication: all project documents were uploaded to the project intranet; internal newsletters were prepared on a regular basis and were shared with the consortium.
Potential Impact:
Myasterix planned to achieve an impact on five levels. Below, we have described how Myasterix contributed to the expected impact:
1. on MG patients through the availability of a more targeted therapeutic approach with fewer and less severe side effects;
Since the phase 1b was not designed neither powered to assess efficacy and the immunogenic response was not high enough to induce a significant improvement of Myasthenia Gravis, as assessed by clinical scales, there is currently no impact on the population of patients and on society costs and further clinical trials with an optimized more potent vaccine are needed. However, the safety profile is excellent, and some patients were improved at the end of the study. Additionally, an excellent collaboration was established with the clinical centre (UZA) which demonstrated an extensive expertise in Myasthenia Gravis and a good access to patients. This might be helpful for potential future trials.
The licensing discussions with some companies, notably from South Korea and Japan is likely to allow a faster availability to some patients in parts of the world compared to a situation where only approval in Europe and a stand-alone strategy would have been developed.
2. on innovation and competitiveness as the approach can be used in other autoimmune diseases);
CuraVac, as part of its business plan, still intends to develop the same therapeutic vaccination strategy (based on complementary peptides) for other autoimmune diseases. The diseases still need to be identified but will be with high unmet needs. If the next investment round of CuraVac is successfully completed, the Myasterix project would have allowed to initiate innovative approached to treat or cure other autoimmune diseases in the future.
3. on the participating SMEs by providing out-licensing opportunities and scope for further clinical development of the MG vaccine as well as opportunities to develop related vaccines);
The main impact is on the participating SME CuraVac. CuraVac participated in many business forums such as BIOVISION, BIO and BIO-Europe conferences to meet with pharmaceutical and biotechnology companies. Many licensing discussions took place with different companies and, although no firm licence has been signed yet, it was necessary to “prime” the discussions with these companies. It is expected that one or several of the ongoing discussions will lead to the signature of a collaboration agreement with a larger company and allow the faster development of the CV-MG therapy in different parts of the world.
During the project, Aepodia could develop its expertise in therapeutic vaccines and immunology, and reinforce its knowledge of neurology and gain expertise in myasthenia gravis.
piCHEM further strengthened its position as leader of complex peptide manufacturer and gained additional knowledge in peptide-protein conjugation. During the course of the project, piCHEM moved to larger facilities with additional laboratories and GMP production rooms and the Myasterix project was one amongst many other to contribute to this growth in the piCHEM’s activities.
4. on reducing the cost of MG therapy and the treatment of autoimmune diseases generally; and
This is not yet achieved but will be the case if the therapy is successfully brought to the market. Our market analysis has shown that the current cost of MG patients is very high and, if the CV-MG is efficacious and approved, it could lead to a tremendous reduction of the cost of MG for society.
5. on society by reducing the disease burden of MG on health systems around the world.
If and when the therapy is approved, it would have a tremendous impact on the economic burden as well. Our market analysis has shown that MG is a very expensive disease for the health care systems.
The main dissemination activities in the project were as described below.
- Preparation of a project brochure: A brochure in English presenting the general outlines of the project and its participants was prepared and was distributed widely. The pdf version of the brochure is also downloadable from the MYASTERIX public website reaching over 10,000 users. At mid-term, the brochure was modified and updated.
- Development of a project website www.myasterix.eu was set up in 4 languages: English, French, Dutch and German (the languages of the partners) and was regularly updated.
- Press releases were launched throughout the project and can be viewed on the website. In particular, a press release was widely disseminated on the formal start of the phase 1b clinical trial in January 2016. The press release was for instance quoted in the Rhumatos journal La pratique quotidienne en rhumathologie which is read in French hospitals.
- A twitter account was created @Myasterix1 and was regularly updated. Myasterix has 68 followers and follows 118 organisations or individuals. Myasterix published 28 tweets in 2017 and 2018.
- A poster for the BIO2014 and BIO2015 congresses was prepared and presented at BIO2014, BIO2015, BIO2016, and BIO2017.
- Scientific conferences to present the clinical trial, the intermediate and the final results:
o A poster on the first results of the tetanus trial was presented in Oxford at the MGTX meeting on the 8th of January 2016 by the LUMC team.
o Professor Mercelis (UZA) was invited to present the Myasterix phase 1b clinical trial at the 13th International Conference on Myasthenia Gravis and Related Disorders held every 5 years by the New York Academy of Science (NYAS) as a Plenary Speaker on 16th May 2017. Prof. Mercelis (UZA) presented the interim results of the phase 1b. Ellen Strijbos (LUMC) also presented the data from the tetanus study at this congress in the form of a poster.
- 2 publications were written by LUMC.
o Translation and validation of the 15-item Myasthenia Gravis Quality of life scale in Dutch.
o A prospective, placebo controlled study on the humoral immune response to and safety of tetanus revaccination in myasthenia gravis.
- In addition, the consortium had interactions with patient associations: Les A.M.I.S the Belgian Liga-MG and the Dutch Spierziekten Nederland in order to inform patients of the clinical trial and stimulate recruitment interest.
In total, excluding the many business presentations and meetings, 15 oral presentations at a scientific event were made, 4 presentations to a wider public given, 2 posters were presented, 3 press releases circulated, 2 exhibitions, 1 social network account created, 1 conference was organized.
To pave the way for the exploitation of the project results, the following activities were implemented:
- A Market analysis study: The objectives of the study were to know if we could understand if and how patients progress between medications and if we could identify subgroups of patients that are poorly managed on the existing standard of care and hence, bear a large proportion of the costs for insurance and healthcare systems. The main findings and conclusions of the study provided a better understanding of the disease’s socio-economic burden.
- Interactions with regulators: CuraVac had interactions with both the European Medicines Agency and with the US Food and Drug Administration which were useful in the development of the protocol.
- Business development: CuraVac was very active in business development and participated in BIO2015 (Philadelphia), BIO2016 (San Francisco) and Bio-Europe 2015 (Munich). CuraVac participated in the BIO congress in June 2017 in San Diego and met with several companies. During each congress, 20 to 30 meetings were held. CuraVac also participated in BIO2018 congress in Boston. The Biopartnering system was used to select companies with a potential interest in the CV-MG01 product. 23 one-to-one meetings took place and some companies are still evaluating the technology and the clinical trial results. The business development strategy pursued is to grant geographically limited licenses to obtain funds allowing securing and accelerating the clinical developments in Europe and possibly in the USA. CuraVac was in contact with several companies for an early license agreement on the therapy for a limited territory. Nicolas Havelange (CuraVac) travelled to Korea in April 2015 to meet some Korean companies potentially interested in the CV-MG01 for licensing in the region. CuraVac is in contact with several companies for an early license agreement on the therapy but most of the companies decided to wait until the phase 1b results were available. The final results of the phase 1b were communicated and contacts are ongoing with investors and pharmaceutical companies for the next stages of the CV-MG development.
List of Websites:
www.myasterix.eu
Twitter: @Myasterix1