GSK's Long-Acting Injectable Defeats Truvada in HIV Prevention Trial

As it stands, there are two drugs that have been approved by the Food and Drug Administration to be prescribed as PrEP, an HIV prevention strategy that when taken routinely makes it virtually impossible to contract the virus.

Both of these daily drugs, Truvada and Descovy, are manufactured by Gilead. In the last couple years, however, GlaxoSmithKline has been trailing behind Gilead in the HIV treatment market. Soon, they may top them. 

In a recent drug trial involving approximately 4,600 gay and bisexual men and transgender women, ViiV Healthcare’s long-acting injectable, cabotegravir, was found to be 69 percent more effective than Truvada.

In fact, cabotegravir was so effective that the trial was stopped early by an independent monitoring board.

As ViiV Healthcare’s head of research Kimberly Smith noted, a major reason why long-acting injectables are more effective is because it’s administered every two months, whereas once-a-day strategies like Truvada and Descovy must be taken daily.

Daily drugs make users more susceptible to skip doses, or neglect them altogether. That will not be a concern for people who take injectables given that treatment is given every two months. 

“These study results demonstrate that long-acting injectable cabotegravir dosed every two months can successfully reduce HIV acquisition in at-risk MSM and transgender women,” said Kimberly Smith, M.D., Head of Research & Development at ViiV Healthcare. “We are thrilled with the results not only because of the high efficacy of cabotegravir but also because we have demonstrated high efficacy in a study that adequately represents some of the populations most disproportionately impacted by HIV — black MSM in the U.S., young MSM globally and transgender women.”

A spokesperson from GSK told the New York Times that the company will be speaking to drug regulators about speeding up the FDA’s approval of cabotegravir based on the success of the prevention trial.

Cabotegravir is already approved to take in Canada as one of two ingredients in long-acting PrEP strategies. A similar prevention trial testing cabotegravir in cis women is ongoing. It's unclear whether a similar trial will be held for transgender men.