Final Report Summary - IHIVARNA (Therapeutic TriMix / mRNA based Vaccine in Chronic HIV-1 Infected Patients Receiving Antiretroviral Therapy)
Executive Summary:
Currently, over 30 million people worldwide are infected with HIV, most of them living in developing countries. Although combined antiretroviral therapy (cART) has proven to be highly effective to prevent clinical progression and death, by itself it is unable to eradicate the infection, thus necessitating therapy throughout life. Therefore, for an effective control of the HIV epidemic new cost-effective and viable therapeutic strategies need to be evaluated.
A small proportion of HIV infected patients show a lack of clinical progression associated with strict control of viral replication in the absence of any treatment (they have referred as elite controllers). This so-called “functional cure” has been linked with potent HIV-specific immune responses observed in these patients.
Therapeutic vaccinations have emerged as one of the most promising strategies that could restore HIV-specific T-cell responses in HIV infected patients and help them control viral replication without cART. IDIBAPS has reported the most striking results in this field to date, demonstrating that a DC-based vaccine (European patent application number EP12382078.9) was able to significantly control viral load in vaccinated subjects (mean peak reduction of viral load of 94%).
Partner #1 in a double-blind placebo controlled study reported some of the best, most solid data showing that HIV-1 specific immune responses elicited by therapeutic dendritic cell (DC) vaccines pulsed ex vivo with inactivated autologous whole virus could significantly change pVL set-point (mean peak drop of -1.2 log10 copies/ml). Similar efficacy has been found in a preliminary non controlled clinical trial using DC electroporated with mRNA encoding autologous HIV-1 antigens. However, the logistics of developing a specific vaccine by ex vivo manipulating autologous DC for each patient may be prohibitive. Therefore, iHIVARNA consortium propose that in vivo targeting of DC by direct administration of a rational designed HIV mRNA encoding immunomodulating proteins might be an attractive alternative to target DCs in situ. Our candidate is highly innovative: 1. It is a mRNA based immunogen: it is expected to have a good safety profile, it is classified as nongene therapy by the American and German authorities, is easier to produce and to store regardless of the encoded antigen and is not restricted to a defined HLA type of individuals. 2. The HIV antigen encoded by mRNA has been selected with a rational design: based on our previous works selecting viral targets of protective HIV-1 specific T cell responses in 3 large cohorts of HIV infected individuals. 3. The candidate includes TriMix to target DC in vivo: our data suggest that mRNA encoding a mixture of antigen presenting cells activation molecules (CD40L, a constitutive active variant of TLR4 and CD70) significantly enhanced the induction of antigen-specific T cells. If this candidate would be able to obtain the functional cure in at least a proportion of patients it could be applicable to developing countries and would improve the care and cost of HIV infection.
The principal aim of iHIVARNA is to successfully immunize antiretroviral-treated HIV-infected patients with 3 injections of the candidate universal HIV-TriMix-mRNA as an mRNA-based therapeutic vaccine with the final objective of achieving a functional cure of HIV infection (i.e. control of viral load to levels below the threshold of 50 copies/ml and maintenance of high CD4+ T-cell count after discontinuation of antiretroviral therapy). In order to fulfil this aim, the planned steps are:
- To manufacture HIV-TriMix-mRNA in GMP conditions.
- To perform a phase I dose escalation clinical trial and a phase IIa-proof-of-concept clinical trial to test safety, efficacy and immunogenicity.
To ascertain immune and viral predictors and correlates of protection.
Project Context and Objectives:
The primary objective of the iHIVARNA project is to successfully immunize antiretroviral treated HIV-infected patients with an mRNA-based therapeutic vaccine with the final aim of obtaining a functional cure of the patient. The vaccine candidate (HIV-TriMix-mRNA) is a combination of rationally designed HIV antigen, TriMix, and mRNA, and will be tested in a phase I and phase II clinical trial during the project.
The project is tackled by a program of seven workpackages (WPs). Specific objectives of the WPs are as follows:
WP1: Scientific coordination
- To provide overall scientific direction and to drive the progress of the project, steering efforts of the partners for the achievement of milestones and ensuring that the work is undertaken with appropriate quality levels.
- To provide a unified scientific, technological and strategic view throughout the project implementation.
- To continuously assess the degree of fulfilment of the project objectives.
- To ensure that the project is not hampered by ethical problems and respects all relevant international and national regulations in this regard.
WP2: Clinical Trials management and development
- To undertake the non-clinical studies.
- To Manufacture GMP-grade messenger RNA for the phase I and phase II clinical trials. (Achieved for phase I)
WP3: Clinical Trial phase I Implementation
- To perform a phase I, open label dose escalation.
- To evaluate the safety of intranodal (IN) injection of HIV-TriMix-mRNA in order to select the optimal dose for the phase IIa clinical trial.
- To assess preliminary data of immunogenicity in humans.
WP4: Clinical Trial fase lla implementation
- To assess the safety and toxicity of immunotherapy using iHIVARNA and TriMix mRNA for 70 patients (40 HIV/TriMix, 15 control/TriMix, and 15 control/saline)
- To determine the immunogenicity of the vaccine preparation
- To determine the effects of treatment interruption after immunotherapy on blood values, plasma viral load and patients’ clinical well-being.
WP5: Data Analysis
- To study the effect of HIV-TriMix-mRNA as compared to control vaccination on:
• CD8/CD4+ T-cell cytokine responses (ELISPOT and ICS)
• CD8+ T-cell HIV suppressive capacity
• Proviral DNA reservoir and intracellular unspliced and multiple spliced HIV RNA
• Cultivability and fitness of HIV
• Emergence of viral escape mutations in sieve effect analyses
WP6: Dissemination and exploitation
- To design a plan that allows for optimal communication within the project and the dissemination of information and knowledge generated by the project to relevant stakeholders.
- To design and deploy the tools that needed to implement the plan.
- To undertake extensive dissemination activities according to the communication plan.
- To facilitate the take-up and use of results, in particular by promoting the definition of exploitation strategies, IPRs management policies and knowledge management activities and addressed to:
o Support participating partners -and specially the SMEs- in the use and protection of the project results in order to maximise their potential for market uptake.
o Conclude and follow-up on suitable arrangements with respect to results ownership and access rights so as to maximise their use without hampering its exploitation prospective.
o Devise specific exploitation/business plans for the resulting foreground with special emphasis on increasing the competitiveness of the participant SMEs.
WP7: Project Management
- To set-up a project management structure that ensures an efficient operational management, including administrative, financial and legal issues, and appropriate liaison with the European Commission.
- To ensure that the project is appropriately managed according to the work plan, supporting the Scientific Coordination in organising and supervising the work.
- To compile resources, procedures and tools to ensure that all results are delivered on time, with an adequate quality level and within cost, including quality control procedures on deliverables and interim and final review of the project achievements from a management perspective.
- To enable appropriate communication and work dynamics to help drive the whole Consortium as a team towards successful completion.
Project Results:
1.3.1. Development of a naked mRNA HIV-1 therapeutic vaccine.
For the iHIVARNA vaccine Drug Products (DP) two Drug Substances (DS) are produced namely:
- HIVACAT: Chimeric RNA containing different HIV antigens
- TriMix: A mixture of three mRNAs CD70, CD40L and a constitutively active TLR4 at a ratio of 1:1:1, which induces maturation and stimulation of dendritic cells
Different combinations and concentrations of these DS are being prepared as Drug Product (DP) for use in the phase I clinical trial:
- TriMix_100: 100 µg TriMix RNA per injection
- TriMix_300: 300 µg TriMix RNA per injection
- iHIVARNA-01.1: 300 µg TriMix RNA + 300 µg HIVACAT RNA per injection
- iHIVARNA-01.2: 300 µg TriMix RNA + 600 µg HIVACAT RNA per injection
- iHIVARNA-01.3: 300 µg TriMix RNA + 900 µg HIVACAT RNA per injection
Given the results of the phase I study, iHIVARNA-01-3 has been selected to perform the phase II clinical trial.
1.3.2. Preclinical assessment
In addition to a toxicological assessment, a preclinical assessment has been performed.
We evaluated a new mRNA-based therapeutic vaccine against HIV-1-encoding activation signals (TriMix: CD40LþCD70þcaTLR4) combined with rationally selected antigenic sequences [HIVACAT T-cell immunogen (HTI)] sequence: comprises 16 joined fragments from Gag, Pol, Vif, and Nef). For this purpose, peripheral blood mononuclear cells from HIV-1-infected individuals on cART, lymph node explants from noninfected humans, and splenocytes from immunized mice were collected and several immune functions were measured. Electroporation of immature monocyte-derived dendritic cells from HIV- infected patients with mRNA encoding HTI þ TriMix potently activated dendritic cells which resulted in upregulation of maturation markers and cytokine production and T-cell stimulation, as evidenced by enhanced proliferation and cytokine secretion (IFN-g). Responses were HIV specific and were predominantly targeted against the sequences included in HTI. These findings were confirmed in human lymph node explants exposed to HTI þ TriMix mRNA. Intranodal immunizations with HTI mRNA in a mouse model increased antigen-specific cytotoxic T-lymphocyte responses. The addition of TriMix further enhanced cytotoxic responses. Our results suggest that uptake of mRNA, encoding strong activation signals and a potent HIV antigen, confers a T-cell stimulatory capacity to dendritic cells and enhances their ability to stimulate antigen-specific immunity. These findings may pave the way for therapeutic HIV vaccine strategies based on antigen-encoding RNA to specifically target antigen-presenting cells.
1.3.3. Evaluation of other co-formulations based on iHIVARNA
In order to facilitate the use of iHIVARNA.01 as a preventive vaccine against HIV infection, we have tested over 130 formulations of iHIVARNA.01 in our initial screening. We have selected coformulations with 5 nanoparticles and they are being tested in vitro (gold particles, dendrimers, PLA, polymers and nanocapsules of polyarginine and protamine) Preliminary results are available.
1.3.4. Phase I. Final results
We performed the first-in-human clinical trial with naked mRNA (iHIVARNA) encoding HIV antigenic sequences (HTI sequence: comprising 16 joined fragments from Gag, Pol, Vif and Nef) rationally selected to redirect the responses to the most vulnerable viral targets combined with DC activation signals (TriMix:CD40L+CD70+caTLRA4). A dose scalating phase I clinical trial was performed in 21 chronic HIV-1 infected patients who received 3 intranodal doses of mRNA at weeks 0, 2 and 4 as follow: TriMix 100μg (n=3), TriMix 300μg (n=3), TriMix 300μg+HTI 300μg (n=3), TriMix 300 μg+HTI 600μg (n=6), TriMix 300 μg+HTI 900μg (n=6). Primary end-point was safety and secondary-exploratory end-points were immunogenicity (ELISPOT), changes in reservoir (caHIV-DNA and caHIV-RNA), ultrasensitive plasma RNA (usVL) and transcriptome (limma). Overall, the vaccine was safe and well tolerated. No serious adverse events (AEs) were observed. There were 31 grade 1/2 and 1 grade 3 AEs, from which half of grade 1/2 and the grade 3 were definitely not related to the vaccination. Patients who received the highest dose showed a moderate increase in T cell responses spanning HTI sequence (IN) at week 8 whereas no changes were observed in responses against the rest of the HIV-1 proteome (OUT). In addition, the proportion of responders receiving any dose of iHIVARNA (n= 15) increased from 31% at w0 to 80% post-vaccination. This increase was not observed in patients receiving TriMix alone (n=6, from 50% to 67%). Vaccination did no impact on caHIV-DNA levels in any of the studied arms. However, caHIV-RNA expression and usVL were transiently increased in patients receiving the higher doses of TriMix.HTI at weeks 5 and 6. We did not observed differentially expressed genes in any of the groups-wise comparisons, although gene set analysis indicates some effect on pathways such as RNA metabolism and host response to viruses, but with very low significance levels. This phase I exploratory dose-escalating trial showed that iHIVARNA was safe and well tolerated, was able to induce moderate HIV-specific immune responses and transiently increased caHIV-RNA expression. These data support further exploration of iHIVARNA in a phase II study.
1.3.5. Phase IIa preliminary results
Interim analysis : After the inclusion of 34 patients, and the vaccination of 33 patients, recruitment was halted, as decided in the amendment for interim analysis. In the analysis the primary endpoint immunogenicity was tested. For this PBMC were sent to IDIBAPS for a peptide Elispot assay (WP5). The unblinded statistician of the data safety monitoring board (DSMB) calculated that the arm that had received the IMP did not have 0.7log increase in immunogenicity as compared to the baseline and compared to the placebo arm (which received WFI). Since no significant improvement of immunogenicity was observed in the vaccine group as opposed to the placebo group, further recruitment and inclusion was stopped, for futility which was according to the amendment.
Regretfully, final results will not be available before the end of the project. However, the phase IIa clinical trial will end the first week of February. An evaluation of the impact of the vaccine on immune responses (assessed not only by ELISPOT, but also by other CD8 T cell mediated HIV suppression capacity), reservoir, transcriptome and microbiome is ongoing. The results will be analyzed after the unblinding of the study and we hope that the final results will be available for the second half of 2018. We expect that these results could improve our knowledge of the impact of mRNA vaccine in HIV pathogenesis and could help to prepare future strategies of functional cure.
Potential Impact:
There is a growing interest in developing curative strategies to tackle HIV infection. A safe, affordable and scalable cure could address both the individual and public health limitations that are associated with lifelong antiretroviral therapy, as recognized by the European Parliament on the EU response to HIV/AIDS in the EU and neighbouring countries, mid-term review of Commission Communication COM(2009)569:
“...having regard to the Rome Statement adopted at the International Aids Society Conference 2011, which calls for more funding for the development of a functional cure for HIV ... Calls on the Commission and Council to provide the resources needed to guarantee equitable access to HIV prevention, testing, treatment, care and support, to address stigma and other barriers to timely access to counselling, testing and early care, to increase investment in research to achieve an effective cure and to improve instruments and actions to address co-infections such as tuberculosis or hepatitis B and C, among others, through improved access to screening and effective access to treatment ...”
iHIVARNA directly addresses this question as it is aimed at developing an innovative therapeutic vaccine against HIV infection with the final objective of inducing HIV specific immune responses to achieve a long-term control of viral replication without antiretroviral therapy (functional cure).
The iHIVARNA new immunogen has characteristics that are aimed at overcoming some of the problems of other therapeutic vaccines against HIV and to be potentially applicable to other diseases:
1. It is an mRNA-based immunogen. Compared with other gene-based approaches such as recombinant viruses or plasmids, mRNA is expected to have a better safety profile because it is a molecule that is only transiently present within the cell and is naturally and quickly degraded. Thus, it was classified as non-gene therapeutic by the American (Food and Drug Administration) and German (Paul Ehrlich Institute) authorities. Compared with proteins, mRNAs are easier to produce and to store regardless of the encoded antigen. In contrast to peptide-based vaccination, mRNA-based vaccination offers the advantage of not being restricted to a defined human leukocyte antigen type of individuals and is thus readily applicable to patients with any human leukocyte antigen haplotype.
2. The HIV antigen selection was based on a rational design and the same approach could be used for other pathogens.
3. The vaccine candidate also includes TriMix to activate DC in vivo. The use of mRNA encoding immunomodulating proteins might be an attractive alternative to potentiate DCs in vivo in other vaccines.
In summary, all efforts in iHIVARNA are devoted to obtain results relevant for the advancement of an HIV functional cure. Final results of phase II clinical trial will be available 2nd half of 2018.
List of Websites:
Project coordinator: Dr. Felipe García, Consorci Institut d'Investigacions Biomediques August Pi i Sunyer
Project website: www.ihivarna.org
List of partners:
• Consorci Institut d’Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS)
• Instituut voor Tropische Geneeskunde (ITM)
• Vrije Universiteit Brussel (VUB)
• eTheRNA NV (eTheRNA)
• Erasmus Universitair Medisch Centrum Rotterdam (EMC)
• Institut de Recerca de la Sida – Caixa (IRSICAIXA)
• Synapse Research Management Partners S.L. (SYNAPSE)
• Asphalion, S.L. (ASPHALION)
Currently, over 30 million people worldwide are infected with HIV, most of them living in developing countries. Although combined antiretroviral therapy (cART) has proven to be highly effective to prevent clinical progression and death, by itself it is unable to eradicate the infection, thus necessitating therapy throughout life. Therefore, for an effective control of the HIV epidemic new cost-effective and viable therapeutic strategies need to be evaluated.
A small proportion of HIV infected patients show a lack of clinical progression associated with strict control of viral replication in the absence of any treatment (they have referred as elite controllers). This so-called “functional cure” has been linked with potent HIV-specific immune responses observed in these patients.
Therapeutic vaccinations have emerged as one of the most promising strategies that could restore HIV-specific T-cell responses in HIV infected patients and help them control viral replication without cART. IDIBAPS has reported the most striking results in this field to date, demonstrating that a DC-based vaccine (European patent application number EP12382078.9) was able to significantly control viral load in vaccinated subjects (mean peak reduction of viral load of 94%).
Partner #1 in a double-blind placebo controlled study reported some of the best, most solid data showing that HIV-1 specific immune responses elicited by therapeutic dendritic cell (DC) vaccines pulsed ex vivo with inactivated autologous whole virus could significantly change pVL set-point (mean peak drop of -1.2 log10 copies/ml). Similar efficacy has been found in a preliminary non controlled clinical trial using DC electroporated with mRNA encoding autologous HIV-1 antigens. However, the logistics of developing a specific vaccine by ex vivo manipulating autologous DC for each patient may be prohibitive. Therefore, iHIVARNA consortium propose that in vivo targeting of DC by direct administration of a rational designed HIV mRNA encoding immunomodulating proteins might be an attractive alternative to target DCs in situ. Our candidate is highly innovative: 1. It is a mRNA based immunogen: it is expected to have a good safety profile, it is classified as nongene therapy by the American and German authorities, is easier to produce and to store regardless of the encoded antigen and is not restricted to a defined HLA type of individuals. 2. The HIV antigen encoded by mRNA has been selected with a rational design: based on our previous works selecting viral targets of protective HIV-1 specific T cell responses in 3 large cohorts of HIV infected individuals. 3. The candidate includes TriMix to target DC in vivo: our data suggest that mRNA encoding a mixture of antigen presenting cells activation molecules (CD40L, a constitutive active variant of TLR4 and CD70) significantly enhanced the induction of antigen-specific T cells. If this candidate would be able to obtain the functional cure in at least a proportion of patients it could be applicable to developing countries and would improve the care and cost of HIV infection.
The principal aim of iHIVARNA is to successfully immunize antiretroviral-treated HIV-infected patients with 3 injections of the candidate universal HIV-TriMix-mRNA as an mRNA-based therapeutic vaccine with the final objective of achieving a functional cure of HIV infection (i.e. control of viral load to levels below the threshold of 50 copies/ml and maintenance of high CD4+ T-cell count after discontinuation of antiretroviral therapy). In order to fulfil this aim, the planned steps are:
- To manufacture HIV-TriMix-mRNA in GMP conditions.
- To perform a phase I dose escalation clinical trial and a phase IIa-proof-of-concept clinical trial to test safety, efficacy and immunogenicity.
To ascertain immune and viral predictors and correlates of protection.
Project Context and Objectives:
The primary objective of the iHIVARNA project is to successfully immunize antiretroviral treated HIV-infected patients with an mRNA-based therapeutic vaccine with the final aim of obtaining a functional cure of the patient. The vaccine candidate (HIV-TriMix-mRNA) is a combination of rationally designed HIV antigen, TriMix, and mRNA, and will be tested in a phase I and phase II clinical trial during the project.
The project is tackled by a program of seven workpackages (WPs). Specific objectives of the WPs are as follows:
WP1: Scientific coordination
- To provide overall scientific direction and to drive the progress of the project, steering efforts of the partners for the achievement of milestones and ensuring that the work is undertaken with appropriate quality levels.
- To provide a unified scientific, technological and strategic view throughout the project implementation.
- To continuously assess the degree of fulfilment of the project objectives.
- To ensure that the project is not hampered by ethical problems and respects all relevant international and national regulations in this regard.
WP2: Clinical Trials management and development
- To undertake the non-clinical studies.
- To Manufacture GMP-grade messenger RNA for the phase I and phase II clinical trials. (Achieved for phase I)
WP3: Clinical Trial phase I Implementation
- To perform a phase I, open label dose escalation.
- To evaluate the safety of intranodal (IN) injection of HIV-TriMix-mRNA in order to select the optimal dose for the phase IIa clinical trial.
- To assess preliminary data of immunogenicity in humans.
WP4: Clinical Trial fase lla implementation
- To assess the safety and toxicity of immunotherapy using iHIVARNA and TriMix mRNA for 70 patients (40 HIV/TriMix, 15 control/TriMix, and 15 control/saline)
- To determine the immunogenicity of the vaccine preparation
- To determine the effects of treatment interruption after immunotherapy on blood values, plasma viral load and patients’ clinical well-being.
WP5: Data Analysis
- To study the effect of HIV-TriMix-mRNA as compared to control vaccination on:
• CD8/CD4+ T-cell cytokine responses (ELISPOT and ICS)
• CD8+ T-cell HIV suppressive capacity
• Proviral DNA reservoir and intracellular unspliced and multiple spliced HIV RNA
• Cultivability and fitness of HIV
• Emergence of viral escape mutations in sieve effect analyses
WP6: Dissemination and exploitation
- To design a plan that allows for optimal communication within the project and the dissemination of information and knowledge generated by the project to relevant stakeholders.
- To design and deploy the tools that needed to implement the plan.
- To undertake extensive dissemination activities according to the communication plan.
- To facilitate the take-up and use of results, in particular by promoting the definition of exploitation strategies, IPRs management policies and knowledge management activities and addressed to:
o Support participating partners -and specially the SMEs- in the use and protection of the project results in order to maximise their potential for market uptake.
o Conclude and follow-up on suitable arrangements with respect to results ownership and access rights so as to maximise their use without hampering its exploitation prospective.
o Devise specific exploitation/business plans for the resulting foreground with special emphasis on increasing the competitiveness of the participant SMEs.
WP7: Project Management
- To set-up a project management structure that ensures an efficient operational management, including administrative, financial and legal issues, and appropriate liaison with the European Commission.
- To ensure that the project is appropriately managed according to the work plan, supporting the Scientific Coordination in organising and supervising the work.
- To compile resources, procedures and tools to ensure that all results are delivered on time, with an adequate quality level and within cost, including quality control procedures on deliverables and interim and final review of the project achievements from a management perspective.
- To enable appropriate communication and work dynamics to help drive the whole Consortium as a team towards successful completion.
Project Results:
1.3.1. Development of a naked mRNA HIV-1 therapeutic vaccine.
For the iHIVARNA vaccine Drug Products (DP) two Drug Substances (DS) are produced namely:
- HIVACAT: Chimeric RNA containing different HIV antigens
- TriMix: A mixture of three mRNAs CD70, CD40L and a constitutively active TLR4 at a ratio of 1:1:1, which induces maturation and stimulation of dendritic cells
Different combinations and concentrations of these DS are being prepared as Drug Product (DP) for use in the phase I clinical trial:
- TriMix_100: 100 µg TriMix RNA per injection
- TriMix_300: 300 µg TriMix RNA per injection
- iHIVARNA-01.1: 300 µg TriMix RNA + 300 µg HIVACAT RNA per injection
- iHIVARNA-01.2: 300 µg TriMix RNA + 600 µg HIVACAT RNA per injection
- iHIVARNA-01.3: 300 µg TriMix RNA + 900 µg HIVACAT RNA per injection
Given the results of the phase I study, iHIVARNA-01-3 has been selected to perform the phase II clinical trial.
1.3.2. Preclinical assessment
In addition to a toxicological assessment, a preclinical assessment has been performed.
We evaluated a new mRNA-based therapeutic vaccine against HIV-1-encoding activation signals (TriMix: CD40LþCD70þcaTLR4) combined with rationally selected antigenic sequences [HIVACAT T-cell immunogen (HTI)] sequence: comprises 16 joined fragments from Gag, Pol, Vif, and Nef). For this purpose, peripheral blood mononuclear cells from HIV-1-infected individuals on cART, lymph node explants from noninfected humans, and splenocytes from immunized mice were collected and several immune functions were measured. Electroporation of immature monocyte-derived dendritic cells from HIV- infected patients with mRNA encoding HTI þ TriMix potently activated dendritic cells which resulted in upregulation of maturation markers and cytokine production and T-cell stimulation, as evidenced by enhanced proliferation and cytokine secretion (IFN-g). Responses were HIV specific and were predominantly targeted against the sequences included in HTI. These findings were confirmed in human lymph node explants exposed to HTI þ TriMix mRNA. Intranodal immunizations with HTI mRNA in a mouse model increased antigen-specific cytotoxic T-lymphocyte responses. The addition of TriMix further enhanced cytotoxic responses. Our results suggest that uptake of mRNA, encoding strong activation signals and a potent HIV antigen, confers a T-cell stimulatory capacity to dendritic cells and enhances their ability to stimulate antigen-specific immunity. These findings may pave the way for therapeutic HIV vaccine strategies based on antigen-encoding RNA to specifically target antigen-presenting cells.
1.3.3. Evaluation of other co-formulations based on iHIVARNA
In order to facilitate the use of iHIVARNA.01 as a preventive vaccine against HIV infection, we have tested over 130 formulations of iHIVARNA.01 in our initial screening. We have selected coformulations with 5 nanoparticles and they are being tested in vitro (gold particles, dendrimers, PLA, polymers and nanocapsules of polyarginine and protamine) Preliminary results are available.
1.3.4. Phase I. Final results
We performed the first-in-human clinical trial with naked mRNA (iHIVARNA) encoding HIV antigenic sequences (HTI sequence: comprising 16 joined fragments from Gag, Pol, Vif and Nef) rationally selected to redirect the responses to the most vulnerable viral targets combined with DC activation signals (TriMix:CD40L+CD70+caTLRA4). A dose scalating phase I clinical trial was performed in 21 chronic HIV-1 infected patients who received 3 intranodal doses of mRNA at weeks 0, 2 and 4 as follow: TriMix 100μg (n=3), TriMix 300μg (n=3), TriMix 300μg+HTI 300μg (n=3), TriMix 300 μg+HTI 600μg (n=6), TriMix 300 μg+HTI 900μg (n=6). Primary end-point was safety and secondary-exploratory end-points were immunogenicity (ELISPOT), changes in reservoir (caHIV-DNA and caHIV-RNA), ultrasensitive plasma RNA (usVL) and transcriptome (limma). Overall, the vaccine was safe and well tolerated. No serious adverse events (AEs) were observed. There were 31 grade 1/2 and 1 grade 3 AEs, from which half of grade 1/2 and the grade 3 were definitely not related to the vaccination. Patients who received the highest dose showed a moderate increase in T cell responses spanning HTI sequence (IN) at week 8 whereas no changes were observed in responses against the rest of the HIV-1 proteome (OUT). In addition, the proportion of responders receiving any dose of iHIVARNA (n= 15) increased from 31% at w0 to 80% post-vaccination. This increase was not observed in patients receiving TriMix alone (n=6, from 50% to 67%). Vaccination did no impact on caHIV-DNA levels in any of the studied arms. However, caHIV-RNA expression and usVL were transiently increased in patients receiving the higher doses of TriMix.HTI at weeks 5 and 6. We did not observed differentially expressed genes in any of the groups-wise comparisons, although gene set analysis indicates some effect on pathways such as RNA metabolism and host response to viruses, but with very low significance levels. This phase I exploratory dose-escalating trial showed that iHIVARNA was safe and well tolerated, was able to induce moderate HIV-specific immune responses and transiently increased caHIV-RNA expression. These data support further exploration of iHIVARNA in a phase II study.
1.3.5. Phase IIa preliminary results
Interim analysis : After the inclusion of 34 patients, and the vaccination of 33 patients, recruitment was halted, as decided in the amendment for interim analysis. In the analysis the primary endpoint immunogenicity was tested. For this PBMC were sent to IDIBAPS for a peptide Elispot assay (WP5). The unblinded statistician of the data safety monitoring board (DSMB) calculated that the arm that had received the IMP did not have 0.7log increase in immunogenicity as compared to the baseline and compared to the placebo arm (which received WFI). Since no significant improvement of immunogenicity was observed in the vaccine group as opposed to the placebo group, further recruitment and inclusion was stopped, for futility which was according to the amendment.
Regretfully, final results will not be available before the end of the project. However, the phase IIa clinical trial will end the first week of February. An evaluation of the impact of the vaccine on immune responses (assessed not only by ELISPOT, but also by other CD8 T cell mediated HIV suppression capacity), reservoir, transcriptome and microbiome is ongoing. The results will be analyzed after the unblinding of the study and we hope that the final results will be available for the second half of 2018. We expect that these results could improve our knowledge of the impact of mRNA vaccine in HIV pathogenesis and could help to prepare future strategies of functional cure.
Potential Impact:
There is a growing interest in developing curative strategies to tackle HIV infection. A safe, affordable and scalable cure could address both the individual and public health limitations that are associated with lifelong antiretroviral therapy, as recognized by the European Parliament on the EU response to HIV/AIDS in the EU and neighbouring countries, mid-term review of Commission Communication COM(2009)569:
“...having regard to the Rome Statement adopted at the International Aids Society Conference 2011, which calls for more funding for the development of a functional cure for HIV ... Calls on the Commission and Council to provide the resources needed to guarantee equitable access to HIV prevention, testing, treatment, care and support, to address stigma and other barriers to timely access to counselling, testing and early care, to increase investment in research to achieve an effective cure and to improve instruments and actions to address co-infections such as tuberculosis or hepatitis B and C, among others, through improved access to screening and effective access to treatment ...”
iHIVARNA directly addresses this question as it is aimed at developing an innovative therapeutic vaccine against HIV infection with the final objective of inducing HIV specific immune responses to achieve a long-term control of viral replication without antiretroviral therapy (functional cure).
The iHIVARNA new immunogen has characteristics that are aimed at overcoming some of the problems of other therapeutic vaccines against HIV and to be potentially applicable to other diseases:
1. It is an mRNA-based immunogen. Compared with other gene-based approaches such as recombinant viruses or plasmids, mRNA is expected to have a better safety profile because it is a molecule that is only transiently present within the cell and is naturally and quickly degraded. Thus, it was classified as non-gene therapeutic by the American (Food and Drug Administration) and German (Paul Ehrlich Institute) authorities. Compared with proteins, mRNAs are easier to produce and to store regardless of the encoded antigen. In contrast to peptide-based vaccination, mRNA-based vaccination offers the advantage of not being restricted to a defined human leukocyte antigen type of individuals and is thus readily applicable to patients with any human leukocyte antigen haplotype.
2. The HIV antigen selection was based on a rational design and the same approach could be used for other pathogens.
3. The vaccine candidate also includes TriMix to activate DC in vivo. The use of mRNA encoding immunomodulating proteins might be an attractive alternative to potentiate DCs in vivo in other vaccines.
In summary, all efforts in iHIVARNA are devoted to obtain results relevant for the advancement of an HIV functional cure. Final results of phase II clinical trial will be available 2nd half of 2018.
List of Websites:
Project coordinator: Dr. Felipe García, Consorci Institut d'Investigacions Biomediques August Pi i Sunyer
Project website: www.ihivarna.org
List of partners:
• Consorci Institut d’Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS)
• Instituut voor Tropische Geneeskunde (ITM)
• Vrije Universiteit Brussel (VUB)
• eTheRNA NV (eTheRNA)
• Erasmus Universitair Medisch Centrum Rotterdam (EMC)
• Institut de Recerca de la Sida – Caixa (IRSICAIXA)
• Synapse Research Management Partners S.L. (SYNAPSE)
• Asphalion, S.L. (ASPHALION)