HIV vaccine: Johnson & Johnson 'Imbokodo' trial faces blow in Sub-Saharan Africa

Johnson & Johnson's (J&J) HIV vaccine regimen has failed to produce expected results in the clinical trials conducted in Sub-Saharan Africa. As per reports, the final stage "Imbokodo" trials conducted on approximately 2,600 participants rendered ineffective protection against the virus, the company informed US Health Officials. As per the primary analysis, the data reflected an efficacy estimate of 25.2%, but with a wide confidence interval that crossed zero (-10.5% to 49.3%), J&J informed in a statement on Wednesday. Despite the safety, the Adenovirus26-based Mosiac vaccine did not produce the anticipated reduction in the overall risk of HIV.

"HIV remains a global threat, and a safe, efficacious and accessible HIV vaccine is still needed to contribute towards curbing new infections and providing a durable end to the pandemic,” Mitchell Warren, Director of AVAC

As per the Global Advocacy for HIV Prevention (AVAC) press release, the clinical trials were conducted on 2,637 cisgender women from five Sub-Sahara African countries namely, 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,” AVAC informed. However, the highly-anticipated concept trial HVTN 705/HPX2008 did not display the pre-determined criteria for efficacy against the Human Immunodeficiency Virus (HIV) strain in sub-Saharan Africa.

J&J joined hands with AVAC to conduct the phase 3 trials in the Sub-Saharan population. "It is very disappointing that this particular vaccine candidate did not work in this trial, but the trial was well-conducted and got an answer quickly," said Mitchell Warren, Executive Director of AVAC.

Meanwhile, AVAC and J&J expressed gratitude towards the 2000+ women for their "enormous contribution" to the trial. The statement by AVAC also informed that J&J has decided to continue the HIV vaccine Mosaico trial, which is a companion study to be conducted on homosexuals and transgender in America and Europe.

'Will continue efforts to find HIV vaccine'

To achieve complete success in the ongoing quest, Anthony Fauci (Director of US National Institute of Allergy and Infectious Diseases and patron of project) asserted that the follow-up trials will be based on the "knowledge learned" from the Imbokodo trial. "Will continue our efforts to find a vaccine that will be protective against HIV," Fauci told the reporters. Warren too echoed a similar determination. "This is in no way the end of the search for HIV vaccine. We hope for a positive outcome for the ongoing Mosaico and PrEPVacc studies," she said.

The battle against morbid HIV continues

After four decades of the first-ever HIV AIDS case, scientists have made incredible progress in treatment and prevention from the virus. As per reports, medicines like OralPrep have produced 99% protection against the virus. However, the challenges continue to manifold as HIV has thousands of variants inside each person. Additionally, the "retrovirus" characteristics allow it to launch itself on the host cell and convert into an irreversible malignant form.

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