J&J Stops Work on HIV Vaccine After Failure in Phase 3 Clinical Trial

An experimental Johnson & Johnson vaccine for preventing HIV infection has failed a late-stage clinical trial, leading the pharmaceutical giant to stop further work on the program.

Specific clinical trial results were not disclosed. But J&J’s Janssen subsidiary announced Wednesday that the independent data and safety monitoring board for the study concluded that compared to a placebo, the vaccine was not effective in preventing HIV infection and the study was unlikely to meet the main goal of showing efficacy. No safety issues were reported with the vaccine regimen.

J&J developed the vaccine with different immunogens, which are vaccine components that feature parts of many HIV subtypes. The vaccine delivers those immunogens via a strain of adenovirus that’s engineered so that it does not cause infection. The hope was the “mosaic” immunogens would spark immunity against a wide variety of HIV strains from around the world.

The Phase 3 clinical trial, which began in 2019, enrolled 3,900 cisgender men as well as transgender individuals who have sex cisgender men and/or transgender people. This study population represents groups vulnerable to HIV. Participants were enrolled at more than 50 sites in Argentina, Brazil, Italy, Mexico, Peru, Poland, Puerto Rico, Spain, and the U.S.

The vaccine regimen was four injections administered over the course of one year. The third and fourth shots in the regimen included an adjuvant, an ingredient that boosts the immune response. Vaccination of trial participants was completed last October. J&J said participants are being notified of the decision to stop the study and further analyses of the data are underway.

“We are disappointed with this outcome and stand in solidarity with the people and communities vulnerable to and affected by HIV,” Penny Heaton, global therapeutic area head, vaccines, at Janssen Research & Development, said in a prepared statement.

The Phase 3 failure comes nearly 17 months after the J&J HIV vaccine candidate failed a mid-stage clinical trial enrolling young, heterosexual women in southern Africa. That study employed a vaccine regimen similar to that of the Phase 3 trial. Despite the Phase 2 failure, J&J continued the Phase 3 study because that trial included strains from different regions and evaluated a different study population.

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