An HIV/AIDS vaccine trial Johnson & Johnson has failed to reduce the overall risk of HIV among women in five sub-Saharan African countries.
The Imbokodo study which has been on for a number of years was tried mainly in Southern African countries.
But Johnson & Johnson and partners today announced that the Imbokodo study or known as HVTN 705/ HPX2008, did not significantly reduce the overall risk of HIV acquisition among over 2,600 women. A statement featured by AVAC- a Global Advocacy For HIV Prevention said while the Imbokodo results were disappointing, HIV vaccine research must continue.
Findings indicate that the Adenovirus26-based mosaic vaccine regimen was shown to be safe, but it did not meet pre-defined criteria for efficacy to warrant moving forward for longer follow-up.
“AVAC recognizes the enormous contribution of the 2,637 women from five countries in Southern Africa who participated in the trial, and we congratulate the trial teams at sites and across the globe for their work on a superbly run study,” said Nandisile Luthuli,
The Imbokodo study evaluated whether an Adenovirus26-based mosaic vaccine regimen could safely and effectively reduce the rate of new HIV infections among 2,637 cisgender women in 23 sites in Malawi, Mozambique, South Africa, Zambia and Zimbabwe.
Participants received a total of four doses over 12 months of either a prime-boost vaccine regimen of a mosaic viral-vectored vaccine, Adeno26.Mos4.
HIV (Ad26 prime) and an aluminum phosphate-adjuvanted clade C gp140 protein (boost), or a placebo.
Johnson & Johnson reported today in a press release that primary analysis of the data showed an efficacy estimate of 25.2 percent, but with a wide confidence interval that crossed zero (-10.5% to 49.3%).
The press release also noted high HIV incidence rates among the women in the trial.
A companion study, the Phase III Mosaico trial, will continue. The Mosaico study uses a similar regimen with the same Ad26 platform for the prime vaccine, but using a different form of protein boost.
The Phase III study, also known as HVTN 706/HPX3002, is currently enrolling 3,800 men and transgender people in eight countries in the Americas and Europe.
While the Imbokodo study did not provide sufficient protection to continue, there were no safety concerns with the Adenovirus26-based mosaic vaccine candidate.
The Ad26 platform delivers a protein, known as an antigen, to stimulate an immune response. The platform has proven effective in other successful vaccines, including for Ebola and COVID-19.
There is every reason to have confidence in the effectiveness of the Ad26-based Ebola and COVID-19 vaccines that have been important in helping to curb Ebola outbreaks and blunt the current COVID-19 pandemic.