NIH Launches Study to Evaluate Three mRNA Vaccines for HIV

The National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health (NIH), has launched a Phase I clinical trial evaluating three experimental HIV vaccines based on a messenger RNA (mRNA) platform — a technology used in several approved COVID-19 vaccines. NIAID is sponsoring the study, called HVTN 302, conducted by the NIAID-funded HIV Vaccine Trials Network (HVTN) based at Fred Hutchinson Cancer Research Center in Seattle.

The HVTN 302 study will examine whether the following three experimental HIV mRNA vaccines are safe and can induce an immune response: 1) BG505 MD39.3 mRNA, 2) BG505 MD39.3 gp151 mRNA and 3) BG505 MD39.3 gp151 CD4KO mRNA. Each investigational vaccine candidate is designed to present the spike protein found on the surface of HIV that facilitates entry into human cells. Each of the experimental vaccines encodes for different but highly related, stabilized proteins. None of the three vaccine candidates can cause HIV infection.

Led by principal investigators Jesse Clark, MD, of the University of California Los Angeles, and Sharon Riddler, MD, of the University of Pittsburgh, the HVTN 302 study will enroll up to 108 adults ages 18 years to 55 years at 11 sites in Birmingham, Ala., Boston, Los Angeles, New York City, Philadelphia, Pittsburgh, Rochester, N.Y., and Seattle. Each participant will be randomly assigned to one of six groups each receiving three vaccinations of one of the experimental vaccines. The first three groups (18 participants each), called Group A, will receive intramuscular injections of 100 micrograms (mcg) of their assigned vaccine candidate at the initial visit, at month two and again at month six. Participants in Group A will be evaluated two weeks after initial vaccination to ensure safety criteria have been met. If so, the remaining three groups of 18 participants each (Group B) will be vaccinated with 250 mcg of the assigned investigational vaccine, followed by injections two months and six months after the initial vaccination.

Safety and immune responses will be examined via blood and lymph node fine-needle aspiration samples taken at specified timepoints throughout the trial. Clinical staff will closely monitor participant safety throughout the study. The clinical trial is expected to be completed by July 2023.
More information about the HVTN 302 study is available on ClinicalTrials.gov using the identifier NCT05217641.