J&J is discontinuing its HIV vaccine after it failed a phase 3 trial, the latest setback in a decades-long quest to prevent one of the world's most heinous diseases.

The world’s largest pharma by revenue said on Wednesday that the trial’s data safety monitoring board found that the shot did not perform any better than placebos. As a result, the Mosaico study will end.

In a statement, Penny Heaton, M.D., Janessen's global vaccine lead, said that the company was disappointed, adding that "we remain steadfast in our commitment to advancing innovation in HIV, and we hope the data from Mosaico will provide insights for future efforts to develop a safe and effective vaccine."

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This is considered a major setback for the company and the millions of advocates, activists and global health officials who have worked to tackle HIV once and for all.

J&J discovered that the vaccine was about 25% effective, but the lower end of the confidence interval was less than 0. The Mosaico experiment used a one-year regimen that included four doses of the company's adenovirus vector vaccine, as well as a soluble protein in the third and fourth visits.

The National Institutes of Health and the United States Army Medical Research and Development Command collaborated on this research.

Aside from the public health implications, J&J's failure is the latest in a string of poor vaccine performances. First, the company's one-shot COVID vaccine has nearly vanished from global use; it is one of three shots approved in the United States. Moderna has also surpassed the company in the race to develop an RSV vaccine.

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