ViiV Study Shows Investigational HIV Prevention Drug is 66% More Effective than Truvada

ViiV Healthcare announced an injection of cabotegravir given every two months was 66% more effective at preventing HIV infection when compared to Gilead Sciences’ Truvada, according to the final analysis of the HPTN-083 study.

ViiV, an HIV-focused company established through a partnership of GlaxoSmithKline, Pfizer and Shinogi Limited, presented the final data from the HPTN-083 study during AIDS 2020, the international AIDS conference. In the final data analysis, 52 documented cases of HIV were observed in the HPTN 083 trial, with 13 cases occurring in the long-acting cabotegravir arm and 39 cases occurring in the daily Truvada arm. That translates into an HIV contraction rate of 0.41% for cabotegravir and 1.22% for Truvada, the company announced. ViiV said the results from this study will be used to support a submission for regulatory approval of cabotegravir in this indication.

HPTN 083 is a Phase IIb/III randomized, double-blind, clinical trial that is evaluating the safety and efficacy of long-acting, injectable cabotegravir for HIV pre-exposure prophylaxis (PrEP) among men who have sex with men (MSM) and transgender women who have sex with men. In May, ViiV halted the blinded phase of the study following a pre-planned independent Data and Safety Monitoring Board review, which showed that long-acting cabotegravir was highly effective at preventing HIV in the study population. The medication was also well-tolerated by the study participants, ViiV reported.

The HIV Prevention Trials Network (HPTN) 083 study included 4,600 participants across more than 40 sites in North and South America, Asia, and Africa and is one of the first trials to directly compare two active prevention agents. Two-thirds of study participants were under 30 years of age, and 12% were transgender women. Half of the participants in the United States identified as black or African American.

Kimberly Smith, head of research and development at ViiV Healthcare, touted the data. Smith said the data demonstrated cabotegravir’s superiority over Truvada at preventing HIV infection in the study population has the potential to be a game-changing medication in HIV prevention. She said cabotegravir offers a high rate of effectiveness with a greater convenience of dosing every two months as opposed to a daily intake of oral drugs.

“We are thrilled with the results not only because of the high effectiveness of cabotegravir but also because this study adequately represents some of the populations most disproportionately impacted by HIV -- black MSM in the US, young MSM globally and transgender women,” Smith said.

The positive results from the analysis were a shot in the arm for ViiV, which received a Complete Response Letter from the U.S. Food and Drug Administration in December for its combination treatment of cabotegravir and rilpivirine as a long-acting regimen for treatment of HIV-1 infection in virologically suppressed adults. The company sought approval based on non-inferiority data announced in August.

With the HPTN-083 study in the books, eyes are now on the 084 companion study, which began one year after 083. The 084 study is expected to provide data on HIV transfer among females. More than 3,000 sexually active women in seven African countries have enrolled in HPTN 084.