HIV vaccine research supported by the agency: a progress update
The Vaccine Research Institute (VRI) – the laboratory of excellence established by ANRS and Paris-Est Créteil University (UPEC) – and the agency are currently involved in two Phase I vaccine trials in HIV/AIDS (vaccines CD40.HIVRI.Env and DREP-HIV-PT1). Each is evaluating a novel vaccine candidate that uses innovative technologies. The clinical trials are identical in their design. In the first phase, the novel vaccine candidate is studied on its own to ensure that it is well tolerated. The vaccines are then studied alone or in combination with other vaccines in so-called heterologous prime-boost strategies considered optimal in the context of the development of a HIV vaccine, combining protein vaccines (CD40.HIVRI.Env and CN54gp140 vaccines) and DNA vaccines (DNA-HIV-PT123).
In this trial, vaccine candidate CD40.HIVRI.Env is a protein vaccine (HIV envelope protein) coupled with an antibody that enables it to target key immune system cells known as dendritic cells. The VRI has been developing this new platform for several years. This vaccine candidate is administered alone or in combination with another vaccine that is in development (albeit already used in many volunteers), DNA-HIV-PT123 (a DNA vaccine).
The recruitment in France and Switzerland of the 72 healthy volunteers necessary for the trial ended in October 2022. The initial results show the vaccine to be well tolerated and that it induces noteworthy and interesting immune responses. An initial presentation of these results will be made at an upcoming international congress. In light of these results, the team is planning to supplement the ongoing trial by proposing the administration of an additional dose of the vaccine candidate CD40.HIVRI.Env in volunteers who are already vaccinated, and will propose the conduct of larger-scale trials with this vaccine internationally.
The EHVA P01/ANRS VRI08 trial is conducted within the framework of the EHVA (European HIV Vaccine Alliance) consortium, a project funded by the European Union (Horizon 2020 programme) and the Swiss government, for which ANRS | Emerging Infectious Diseases is the sponsor. It involves the use of a vaccine candidate based on another technology, a DNA type vaccine using the DREP platform. The vaccine, called DREP-HIV-PT1, enables expression of the HIV Gp140 envelope protein and is likely to trigger strong and lasting immune responses against this protein.
The first part of Phase I, which is currently taking place in the United Kingdom, is evaluating the safety of the vaccine, which will be injected in 10 healthy volunteers aged 18 to 55 years, at a dose of 0.2 mg or 1 mg. If well tolerated, as the initial results suggest, the second part will commence. This will take place in France and Switzerland and will measure the immune response induced by the vaccine and its duration, while comparing them with those induced by DNA-HIV-PT123. Both vaccines will be combined with CN54gp140: another protein vaccine that is also being evaluated in other clinical trials. The process to recruit the 60 volunteers for this second part is expected to begin at the end of 2022.