Gilead Sciences has reported that additional results from the Phase II/III CAPELLA trial showed its investigational lenacapavir maintained high rates of virologic suppression in heavily treatment-experienced individuals with multi-drug resistant HIV-1.

A long-acting HIV-1 capsid inhibitor, lenacapavir is developed for treating and preventing HIV infection.

The randomised, double-blinded, placebo-controlled global multi-centre study is analysing the antiviral activity of lenacapavir in heavily treatment-experienced people with multi-drug resistant HIV-1 at research centres in North America, Europe, and Asia.

In the trial, 36 subjects with multi-class HIV drug resistance and a detectable viral load who are on a failing regimen were randomised in 2:1 ratio into a blinded manner to receive oral lenacapavir or placebo for 14 days (randomised cohort).

They also continued their failing regimen (functional monotherapy).

An additional 36 participants were part of the non-randomised group.

The study demonstrated that a significantly higher percentage of subjects in the randomised group receiving lenacapavir achieved a clinically meaningful viral load reduction of at least 0.5 log10 copies/mL from baseline versus placebo during the 14-day functional monotherapy period, meeting its primary endpoint.

According to the latest interim efficacy data, subcutaneous administration of lenacapavir every six months maintained increased rates of virologic suppression for 26 weeks in hard-to-treat patients with limited options of therapy and high unmet medical need.

Furthermore, analysis of lenacapavir plus an optimised background regimen showed that 73% of the subjects who reached week 26 after receiving its first subcutaneous dose achieved undetectable viral load (< 50 copies/ml).

Gilead Sciences Virology Therapeutic Area senior vice-president Diana Brainard said: “When treated with lenacapavir plus an optimised background regimen in this study, the majority of participants achieved virologic suppression at 26 weeks of treatment.

“These interim results from the CAPELLA trial demonstrate lenacapavir’s potential to be a foundational, long-acting agent of future HIV treatment regimens.”

Prior to this, Gilead Sciences reported that new long-term data from open-label extensions (OLE) of two Phase III studies (Study 1489 and 1490) of Biktarvy showed sustained efficacy and safety profile for treating treatment-naïve adults with HIV-1.