Based on the results from phase 1 and phase 2a clinical trials that involved almost 400 healthy adults in Rwanda, South Africa, Thailand, Uganda and the United States, a phase 2b trial has been initiated in southern Africa to determine the safety and efficacy of the HIV-1 vaccine candidate in 2,600 women at risk for acquiring HIV.
The new candidate study is being dubbed "HVTN705" or "Imbokodo," which is the isiZulu word for "rock".
Indeed, the NHP 13-19 study of 72 rhesus monkeys assigned one of five vaccine regimens or placebo found that Ad26/Ad26 plus gp140 not only induced similar types of immune responses in humans, but 67% protection against acquisition of SHIV (two-sided Fisher's exact test P=0.007).
This is 1 of only 5 experimental HIV-1 vaccine concepts that have progressed to efficacy trials in humans over 35 years.
RV144 was reported in 2009 to reduce the risk of HIV infection among 16,000 Thai volunteers by 31.2 per cent - deemed insufficient for the drug to be pursued.
For the experiment, the researchers recruited 393 healthy (non-HIV infected) adults ranging in age from 18 to 50 from 12 clinics in East Africa, South Africa, Thailand, and the United States.
They were given four vaccinations over the course of 48 weeks.
This study was funded by Janssen Vaccines & Prevention BV along with International AIDS Vaccine Initiative among others.
Previous attempts at HIV vaccines have been limited to specific strains of the virus found in certain parts of the world.
The vaccine was also safe and well-tolerated, with mild-to-moderate pain at the injection site as the most common adverse event.
This further phase of testing - called a "2b trial" - will hopefully bring promising results. "We have to acknowledge that developing an HIV vaccine is an unprecedented challenge, and we will not know for sure whether this vaccine will protect humans".
"I can not emphasise how badly we need to have a vaccine.to get rid of HIV in the next generation altogether", said Francois Venter of the University of the Witwatersrand Reproductive Health and HIV Institute in South Africa.
Comparatively, the new HIV vaccine yielded better immunization rate and virtually no side effects. At present around 37 million individuals are living with HIV/AIDS with 1.8 million new infections and 1 million deaths annually says the World Health Organization. Every year there are about 1.8 million new cases. Nearly 21 million people were receiving antiretroviral treatment by mid-2017. However, because the mosaic vaccine attacks multiple strains of the virus, doctors would be able to administer it on a much broader scale, and it could potentially be a powerful weapon against HIV if all goes well.
For now, people infected with HIV rely on lifelong virus-suppressing anti-retroviral treatment (ART) to stay healthy.