January 22, 2024

ReiThera Srl, the Ragon Institute and IAVI announce collaboration to advance highly networked T-cell HIV vaccine candidate towards Phase 1 clinical evaluation 

Novel HIV vaccine candidate based on Gorilla adenoviral vector (GRAd-HIV) funded by the Bill & Melinda Gates Foundation to alleviate the disease burden and improve the lives of the millions who lack access to prevention options.

Reithera Ragon IAVI logos

ROME, ITALY, NEW YORK and CAMBRIDGE, USA — January 22, 2024 — ReiThera Srl, the Ragon Institute of Mass General, MIT, and Harvard, and IAVI are pleased to announce a collaboration to develop a novel HIV vaccine candidate that will be composed of ReiThera’s GRAd vector and HIV T-cell epitopes identified by the Ragon Institute, funded by the Bill & Melinda Gates Foundation.

Each partner will be responsible for a different aspect of the program:

  • ReiThera will perform vector engineering and generation, process development, and good manufacturing practice (GMP) manufacture and release for the clinical use of GRAd-HIV vaccine.
  • The Ragon Institute will lead GRAd-HIV preclinical development.
  • IAVI will be the sponsor and execute a Phase 1 clinical trial to evaluate the safety and immunogenicity of the GRAd-HIV vaccine candidate.

ReiThera, a contract development manufacturing organization (CDMO) dedicated to technology and process development and GMP manufacturing for advanced therapies and genetic vaccines; IAVI, an international nonprofit research organization focused on developing vaccines and antibodies against infectious and neglected diseases; and the Ragon Institute, a leading research institute focused on harnessing the immune system to prevent and cure human disease, have entered the manufacturing phase of the collaboration, to begin production of the clinical trial material.

The program will be focused on supporting two key goals:

  1. Development and production of a novel T cell-based HIV vaccine component
  2. Evaluation of the safety and immunogenicity of the novel vaccine in clinical trials in sub-Saharan Africa

The combined expertise of IAVI, ReiThera, and the Ragon Institute will contribute to the development of a novel HIV vaccine component designed to generate a broadly protective potent CD8 T-cell response toward mutationally constrained (‘highly networked’) HIV epitopes. 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. Moreover, CD8+ T-cell targeting of highly networked epitopes distinguished individuals who naturally control HIV, even in the absence of protective HLA alleles.1

ReiThera’s vaccine platform uses a novel proprietary replication-defective Gorilla adenoviral (GRAd) vector, belongingto species C adenoviruses that are considered among the most potent vaccine carriers for the induction of CD8 T-cell responses to the encoded antigens and having a low seroprevalence in humans.

The choice of the GRAd vaccine platform was selected based on evidence generated in preclinical and clinical studies demonstrating a strong induction of T-cell responses to the encoded antigens and a very low frequency of anti-GRAd pre-existing immunity in humans.2

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.

Stefano Colloca, ReiThera’s Chief Technology Officer and co-Founder, said, “We look forward to collaborating with IAVI and the Ragon Institute and continuing 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.”

“We are thrilled to have the opportunity to collaborate with ReiThera and IAVI, with the support of the Bill & Melinda Gates Foundation, to advance the GRAd-HIV highly networked T-cell vaccine candidate towards clinical evaluation,” said Gaurav Gaiha, Ragon faculty member. “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.” Key partners in this program include researchers at the Africa Health Research Institute (AHRI) and the National Institute for Communicable Diseases (NICD) in South Africa, and Mutala Trust and Charles River Medical Group (CRMG) in Zimbabwe.

Sangeetha Sagar, IAVI’s Vice President of Product Development, said, “IAVI’s Product Development Center [PDC] is so pleased to be able to partner with ReiThera and the Ragon Institute to advance the clinical testing of the GRAd-HIV vaccine candidate through a Phase 1 clinical trial. 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.”


About ReiThera Srl
ReiThera Srl is a CDMO company dedicated to technology and process development and GMP manufacturing, providing support for the clinical translation of genetic vaccines and medicinal products for advanced therapies. The company has extensive expertise in developing scalable processes for viral-vector manufacturing and a consolidated experience in GMP production of Adeno-Associated Vector (AAV), Lentivirus, Adeno Viral vector (AdV), Modified Vaccinia Ankara and Herpes Simplex Vector. ReiThera’s core manufacturing capacity is based in a state-of-the-art facility, which includes stirred-tank bioreactors at scales of 50L, 200L, 1000L, and 2000L, as well as fixed-bed bioreactors for cell growth in adherence. The GMP facility also comprises a filling suite and quality control laboratories. ReiThera’s headquarters, R&D laboratories, and GMP facilities are located in Rome, Italy. For more information, visit www.reithera.com.

About the Ragon Institute
The Ragon Institute of Mass General, MIT, and Harvard was established in 2009 with a gift from the Phillip T. and Susan M. Ragon Foundation, with a collaborative scientific mission among these institutions to harness the immune system to combat and cure human disease. The Ragon Institute draws scientists, clinicians and engineers from diverse backgrounds and areas of expertise to study and understand the immune system with the goal of benefiting patients. For more information, visit www.ragoninstitute.org

About IAVI
IAVI is a non-profit scientific research organization dedicated to addressing urgent, unmet global health challenges including HIV, tuberculosis, and emerging infectious diseases. Its mission is to translate scientific discoveries into affordable, globally accessible public health solutions. Read more at iavi.org.

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1 Gaurav D. Gaiha et al. , Structural topology defines protective CD8+ T cell epitopes in the HIV proteome.Science364,480-484 (2019).DOI:10.1126/science.aav5095
2 Stefania Capone et al. , GRAd-COV2 vaccine provides potent and durable humoral and cellular immunity to SARS-CoV-2 in randomized placebo-controlled phase 2 trial.Cell Rep Med. (2023) Jun 20;4(6):101084. DOI: 10.1016/j.xcrm.2023.101084

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Heather Teixeira