Injectable HIV drug Cabotegravir has been found effective in offering protection against the disease if taken by HIV negative person as a form of Pre-Exposure Prophylaxis (PrEP).
In a large scale study code-named HPTN 083 that has been halted because of the coronavirus pandemic, a bi-monthly injection was found to be safe and effective in preventing infection among cisgender men and transgender women who have sex with men.
The study was conducted among 4,500 participants at sites in the Americas, Asia and South Africa. While this study will continue after the pandemic, this efficacy data was revealed after a review by the study data and safety monitoring board (DSMB) who also recommended that instead of some study participants being given a placebo (a medicine-less mimic of the drug), they should now be told that they will either be given Cabotegravir or the oral drugs combination of Tenofovir/ Emtricitabine (TDF/FTC) and Truvada to compare efficacy.
According to a statement released on Monday by the HIV Prevention Trials Network (HPTN), Cabotegravir lowered HIV incidence among the participants.
“Demonstrating conclusively that long-acting injectable Cabotegravir is highly effective almost two years earlier than originally expected is exciting news”, said HPTN 083 protocol chair Raphael J Landovitz, “It's inspiring that we may soon have additional HIV prevention options for at risk individuals who have difficulty with or prefer not to take pills."
Overall, the study that started in December 2016 enrolled 4,570 cisgender men and transgender women in South Africa, Vietnam, Peru, Brazil, Argentina, the US and Thailand among others. Two-thirds of the study participants were under 30 years of age.
A total of 50 incident HIV infections occurred with 38 happening to those that were taking oral PrEP and 12 were enrolled on Cabotegravir, in other words approximately three times the number of incident infections by those on oral treatment.
Now, as soon as they resume the study, the statement notes that participants will be informed about what drug they were enrolled on initially and those on oral treatment will be shifted to the injectable. Those that were receiving the injectable will continue with it.
“Until we have a safe and effective vaccine for HIV, we must continue to find innovative prevention strategies”, said Myron Cohen, the co-principal investigator of the study adding that increasing the number of options for prevention will give people a choice of what works best for them.
However, a sister study HPTN 084 which exclusively enrolled women on the injectable drug is on-going. Uganda is among the participating countries.