Trials halted after potential HIV vaccine found to be ineffective
Leiden-based pharmaceutical company Janssen halted a trial with an HIV vaccine after concluding that the vaccine was not effective in preventing an HIV infection. The Johnson & Johnson subsidiary stressed that there were no safety issues with the vaccine used in the Mosaico study and that all participants who contracted HIV received prompt treatment and care.
“We are disappointed with this outcome and stand in solidarity with the people and communities vulnerable to and affected by HIV,” said Penny Heaton, a medical doctor and head of vaccines at Janssen Research & Development. “Though there have been significant advances in prevention since the beginning of the global epidemic, 1.5 million people acquired HIV in 2021 alone, underscoring the high unmet need for new options.”
During this last phase of the Mosaico study, approximately 3,900 cisgender men and transgender people who have sex with cisgender men or transgender people received the Janssen vaccine or a placebo at over 50 trial sites in various countries. The phase ran from 2019 to October 2022. The participants were then monitored for their immune response, among other things.
The researchers concluded that the vaccine does not protect against HIV. “No safety issues with the vaccine were identified. In light of this, the study will be discontinued,” Janssen said.
“We remain steadfast in our commitment to advancing innovation in HIV, and we hope that data from Mosaico will provide insights for future efforts to develop a safe and effective vaccine,” Heaton said.