GSK’s anti-HIV drug better at preventing infection, trial finds

A GlaxoSmithKline anti-HIV drug given every two months is significantly better at preventing infection than the current standard of care, an international trial has found.

The drug, called cabotegravir, is given by injection as “pre-exposure prophylaxis” or PrEP, a regimen that aims to prevent infection in people who are exposed to HIV.

It is made by ViiV Healthcare, a company that is majority-owned by GSK and also backed by Pfizer and Shionogi.

Public health experts hope that large-scale use of PrEP, along with early and widespread treatment of those infected with HIV, would do more to prevent the virus from being passed on and eventually wipe out a disease that has been around for nearly four decades.

The HPTN 083 trial enrolled 4,566 men and transgender women in the US, Brazil, Peru and elsewhere. It found that cabotegravir was 65 per cent more effective at preventing HIV infection than a daily dose of Truvada, a drug made by Gilead Sciences. Truvada can also be taken intermittently but this regimen was not assessed in the HPTN 083 trial.

The final data analysis reported 52 cases of HIV among participants: 13 in those taking cabotegravir and 39 for people taking Truvada.

Two-thirds of the participants were under 30 and 12 per cent were transgender women. Half of the US participants identified as black or African American, demographic groups that are at higher risk of contracting the virus in the US.

“Taking a daily pill is hard, or stigmatising, or there are other complexities in people’s lives,” said Raphael Landovitz, a University of California Los Angeles doctor who was part of the investigating team.

Truvada is now widely available as a cheaper generic drug, though Gilead hopes patients will switch to Descovy, a pill that has been shown to be as effective, but not superior.

A further study of the efficacy and safety of cabotegravir in women is being conducted.

The news comes as data unveiled at this week’s 23rd International Aids Conference show the Covid-19 pandemic has significantly affected the care received by patients with HIV and increased susceptibility to the disease among those who are at risk.

The study was jointly funded by the US National Institutes of Health and ViiV Healthcare, which along with Gilead provided the drugs.

Cabotegravir is currently not approved anywhere for preventive use.