On Feb. 3, 2021, IAVI and Scripps Research announced a phase 1 clinical trial testing a novel vaccine approach to prevent HIV that produced promising results.

The vaccine showed success in stimulating production of rare immune cells needed to start the process of generating antibodies against the fast-mutating virus; the targeted response was detected in 97 percent of participants who received the vaccine.

The study sets the stage for additional clinical trials that will seek to refine and extend the approach—with the long-term goal of creating a safe and effective HIV vaccine. As a next step, IAVI and Scripps Research are partnering with the biotechnology company Moderna to develop and test an mRNA-based vaccine that harnesses the approach to produce the same beneficial immune cells. Using mRNA technology could significantly accelerate the pace of HIV vaccine development.

HIV, which affects more than 38 million people globally, is known to be among the most difficult viruses to target with a vaccine, in large part because it constantly evolves into different strains to evade the immune system.

The strategy of targeting naïve B cells with specific properties is called “germline-targeting,” as these young B cells display antibodies encoded by unmutated, or “germline” genes. Researchers believe the approach could also be applied to vaccines for other challenging pathogens such as influenza, dengue, Zika, hepatitis C viruses and malaria.