Global HIV vaccine trial ends in disappointment

Experimental vaccine called safe but ineffective

By LOU CHIBBARO JR. | lchibbaro@washblade.com

A worldwide clinical trial of an experimental HIV vaccine involving 3,900 volunteer men who have sex with men and transgender people that some researchers were hopeful would finally result in an effective HIV vaccine was found to be safe but ineffective in preventing HIV infection.

According to a Jan. 18 statement released by the U.S. National Institute of Allergy and Infectious Diseases, which partially funded and helped organize the trial, the vaccine trial is being discontinued and participants were being notified of the findings, with further analysis of the study data planned.

The NIAID statement says the Janssen pharmaceutical company developed the experimental vaccine based on what researchers call “mosaic” immunogens or vaccine components featuring elements of multiple HIV subtypes. It says the goal was to induce immune responses against a wide variety of global HIV strains.

The statement says the investigational vaccine regimen consisted of four injections over a period of one year for the volunteers, who were based in the U.S., Latin America, and Europe. It says an independent data and safety monitoring board, referred to as DSMB, analyzed the data obtained from the vac-

CONTINUED FROM PAGE 10 cine trial, which began in 2019.

“In its scheduled data review, the DSMB determined there were no safety issues with the experimental vaccine regimen,” the statement says. “However, the number of HIV infections were equivalent between the vaccine and placebo arms of the study,” the statement continues. “During the clinical trial, all participants were offered comprehensive HIV prevention tools, including pre-exposure prophylaxis or PrEP,” it says.

“Study staff ensured that participants who acquired HIV during the trial were promptly referred for medical care and treatment,” according to the NIAID statement.

The NIAID study findings prompted the United Nations Program on HIV/AIDS, known as UNAIDS, to issue its own statement this week calling for the aggressive deployment of existing HIV prevention and treatment options as efforts to develop a vaccine continue.

“The disappointment of the vaccine trial further underlies the importance of rolling out available HIV treatment and prevention innovations, including oral PrEP, long acting injectables and the vaginal ring,” UNAIDS Executive Director Winnie Byanyima said in the UNAIDS statement.