GSK Touts HIV Prevention Breakthrough with Long-Acting Injection

A global HIV prevention study found that the long-acting injection cabotegravir was 69 percent more effective than among key patient populations compared to the current standard of care, a daily oral preventative.

The news of the major HIV breakthrough comes from ViiV Healthcare, a global specialist HIV company owned by GlaxoSmithKline (GSK) and Pfizer that recently announced the results of the interim analysis evaluating the safety and efficiency of long-acting investigational injectable cabotegravir for HIV prevention. 

“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,” Kimberly Smith, MD, head of research & development at ViiV Healthcare, stated in the announcement. 

“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 US, young MSM globally and transgender women,” she said.

The study, HIV Prevention Trials Network (HPTN) 083, consisted of nearly 4,600 men who have sex with men (MSM) and transgender women who have sex with men. The study was conducted at research centers in Argentina, Brazil, Peru, United States, South Africa, Thailand, and Vietnam. Each participant received a maximum of three years of blinded study medication. 

Researchers found that cabotegravir was significantly more effective in preventing HIV acquisition in the study group when compared to the current standard of care, emtricitabine/tenofovir disoproxil fumarate 200 mg and 300 mg (FTC/TDF) tablets. 

Gilead earned FDA approval for a daily oral medication for HIV prevention called Truvada in 2012, making the California-based pharmaceutical company a leader in the HIV drugs market.

“Each year, an estimated 1.7 million people are newly diagnosed with HIV. To lower that number, we believe more prevention options are needed in addition to currently available oral tablets for daily use,” Myron S. Cohen, MD, co-principal investigator of the HPTN and the yeargan-bate distinguished professor of medicine, microbiology and immunology and epidemiology at the University of North Caroline (UNC) at Chapel Hill, said in the announcement. 

“If approved, a new injectable agent, such as long-acting cabotegravir administered every two months, could play an important role in reducing HIV transmission and helping to end the HIV epidemic.”

The independent Data and Safety Monitoring Board (DSMB) found that among 50 individuals who contracted HIV, 12 were randomized to the cabotegravir arm and 38 were randomized to the FTC/TDF arm. 

This meant that HIV incident rate was 0.38 percent in the cabotegravir group and 1.21 percent in the FTC/TDF group, GSK stated. Individuals tended to adhere to the FTC/TDF in 87 percent of samples tested.

The study achieved its goal of non-inferiority with the difference approaching superiority in favor of caboegravir, which is pending the final analysis, GSK stated.

Following analysis of the study results, the DSMB recommended the blinded, randomized part of the study be halted and results released. 

Participants who were in the FTC/TDF arm would be offered CAB LA and participants in the CAB LA arm will continue to receive it, GSK stated. Participants who do not want to receive CAB LA will be offered FTC/TDF until the end of the originally planned blinded component of the study. 

GSK noted that currently, more than 3,000 sexually active women in seven African countries have enrolled in HPTN 084 and additional results from HPTN 083 will be presented at an upcoming scientific meeting.

“We continue to be focused on the completion of the companion HPTN 084 study, which will give us important information about the effectiveness of cabotegravir in women. New options are needed for HIV prevention that offers an effective alternative to daily oral PrEP. If approved, this long-acting injectable has the potential to be a game-changer for HIV prevention by reducing the frequency of dosing from 365 days to six times per year,” Smith concluded.