The Desmond Tutu HIV Foundation greets with great disappointment yesterday’s announcement from Johnson & Johnson and partners that the Imbokodo study, a large-scale HIV vaccine proof-of-concept study (HVTN 705) did not show sufficient levels of efficacy to continue the trial to completion. The results showed that the Adenovirus26-based mosaic vaccine regimen, while safe, did not significantly reduce the overall risk of HIV acquisition. The Data Safety Monitoring Board recommended that whilst no safety issues, the vaccine regimen in this trial was unlikely to show sufficient prevention benefit to merit ongoing investigation. The trial had enrolled over 2600 young women in 5 sub-Saharan African countries from communities with a high risk of acquiring HIV.
Dr Katherine Gill, Principal Investigator at the Masiphumelele Research Site, said that while disappointing, the news did not signal an end to the search for an HIV vaccine: “We are sad about this result but will continue to keep young women front and centre of our efforts to combat this devastating virus. We would like to acknowledge our trial participants for volunteering in this important research. Although we didn’t get the answer we were looking for, we understand that we are one step further in our pursuit of a global vaccine to end HIV.”
Study participants will be notified of the results, unblinded and informed whether they were in the study group who received the vaccine or the group who received placebo. Further analysis of the Imbokodo study is ongoing, and the study has provided enough data to progress with key immunological correlates research.
In parallel to the Phase 2b Imbokodo HIV vaccine trial, Janssen is sponsoring the ongoing Phase 3 Mosaico study (HVTN 706/HPX3002) which is testing the safety and efficacy of a different composition of the HIV vaccine regimen among men who have sex with men (MSM) and transgender individuals. This study is being conducted in the Americas and Europe where different strains of HIV are circulating. Given these differentiating factors and following consultations with the Mosaico study independent Data and Safety Monitoring Board (DSMB), it was decided that the Mosaico study will continue at this time. We wish those participants and the trial team best wishes as they proceed.