In January 2024 IAVI announced a collaboration with ReiThera Srl and the Ragon Institute to develop a novel HIV vaccine candidate. This work will be funded by the Bill & Melinda Gates Foundation, with each partner bringing expertise and experience; the vaccine will comprise ReiThera’s GRAd vector and T-cell epitopes identified by the Ragon Institute. The collaboration has entered the “manufacturing phase” to produce the clinical trial material.
The partners will cover different aspect of the programme:
- ReiThera will perform vector engineering and generation, process development, and good manufacturing practice manufacture and release for the clinical use of the vaccine.
- The Ragon Insititute will lead preclinical development.
- IAVI will sponsor and execute a Phase I clinical trial to evaluate the safety and immunogenicity of the candidate.
“The research is aimed to primarily benefit those in lower- and middle-income countries, particularly in Africa, who are disproportionately impacted by HIV and lack access to suitable prevention options.”
Key partners include teams from the Africa Health Research Institute (AHRI) and the National Institute for Communicable Diseases (NICD) in South Africa and the Mutala Trust and Charles River Medical Group (CRMG) in Zimbabwe.
Ragon’s research meets ReiThera’s platform
IAVI states that “prior findings” by the Ragon Institute have shown that “mutation of residues at important network positions disproportionately impaired viral replication and occurred with high frequency in epitopes presented by protective human leukocyte antigen (HLA) class I alleles”. Furthermore, CD8+ T-cell targeting of “highly networked epitopes” distinguished people who “naturally control” HIV, even in the absence of protective HLA alleles.
The target, therefore, is the development of a vaccine component that generates a “broadly protective potent CD8 T-cell response” for “mutationally constrained” epitopes. This will be applied with ReiThera’s novel platform, which uses a proprietary replication-defective Gorilla adenoviral (GRAd) vector. This belongs to species C adenoviruses, considered “among the most potent vaccine carriers” for the purpose of inducing CD8 T-cell responses to encoded antigens, with a low seroprevalence in humans.
The platform was chosen based on evidence from preclinical and clinical studies, in which it demonstrated a “strong” induction of T-cell responses to the encoded antigens and a “very low” frequency of anti-GRAd pre-existing immunity in humans.
Dr Stefano Colloca is ReiThera’s Chief Technology Officer and co-Founder and looks forward to “collaborating with IAVI and the Ragon Institute” to continue to “advance our shared vaccine commitment to address the global challenges posed by HIV”.
“The funding validates the potential of our novel GRAd vector technology to develop vaccine candidates stimulating a strong T-cell response.”
Dr Gaurav Gaiha from the Ragon Institute is “thrilled to have the opportunity to collaborate with ReiThera and IAVI” to take the GRAd-HIV highly networked T-cell vaccine candidate “towards clinical evaluation”.
“We are particularly pleased that this takes place with partners in sub-Saharan Africa, given the immense need for new solutions to curtail the ongoing HIV epidemic.”
Dr Sangeetha Sagar, IAVI’s Vice President of Product Development, said that IAVI’s Product Development Centre (PDC) is “so pleased to be able to partner with ReiThera and the Ragon Institute”.
“The PDC’s purpose is to advance promising biomedical innovations across the global health field by supporting clinical testing and product development, and we are excited to have the opportunity to support this new approach to HIV vaccine development.”
We were glad to speak to Dr Gaiha about his efforts with the Ragon Institute at the Congress in Washington last April; you can check out his interview here. Do join us for this year’s event by getting your tickets at this link, or subscribe for more insights here.
