GSK Provides Insight Into Potential HIV Treatment Data

GSK’s ViiV Healthcare has disclosed clinical data about three prospective long-acting HIV therapies, offering insight into the development of its six-month therapy regimen.

ViiV, primarily owned by GSK with Shionogi and Pfizer as stakeholders, has recognized the desire for long-acting HIV therapies that impose fewer constraints on patients. As Gilead aggressively competes for market share, ViiV is rapidly advancing on many fronts to satisfy demand. The corporation utilized the 2025 Conference on Retroviruses and Opportunistic Infections (CROI) in San Francisco to convey information about three components of its plan of action.

ViiV released phase 2b information regarding its experimental widely neutralizing antibody N6LS. The trial randomized 134 individuals with HIV to get a CD4-binding antibody either orally or via the skin, or to maintain their pre-baseline standard-of-care antiretroviral medication. Patients in the N6LS cohorts got the antibody biannually and long-acting cabotegravir monthly.

After six months, 96% of individuals receiving intravenous N6LS, commonly known as VH109, sustained HIV-1 RNA levels under 50 copies/mL. The outcome in the standard of care cohort was identical. Nonetheless, just 88% of those receiving subcutaneous N6LS sustained HIV-1 RNA levels within the threshold. Virologic failure was determined in two individuals from each N6LS group.

Tolerability was inferior in the subcutaneous cohort, with 16% of the participants exhibiting grade 3 or 4 erythema. The findings guided ViiV’s choice to advance a six-month intravenous dosage of N6LS into the second phase of the study. Halozyme supplied the technology for subcutaneous administration.

ViiV disseminated the N6LS findings the day after the publication of findings from tests on two more compounds that may constitute its six-month therapy regimen. The N6LS study utilized monthly cabotegravir long-acting as its integrase strand transfer inhibitor (INSTI), while ViiV may eventually merge the antibody with its third-generation contender VH184.

At CROI, ViiV presented data showing that 22 grownups who did not previously take antiretroviral therapy experienced a decrease in viral load after starting VH184. This study gave preliminary proof that the INSTI can reduce viral load without leading to drug resistance mutations or serious adverse reactions. However, further research is needed to confirm that the asset can form the basis of ViiV’s regimen, beginning with a phase 1 study of long-acting formulations.

ViiV is thinking about N6LS and its capsid inhibitor VH499 as possible partners for VH184 in its intended six-month treatment regimen. At CROI, the company provided information on VH499, which linked the asset to decreases in viral loads in 23 older individuals who got the candidate in a phase 2 trial. One individual on the low dose had a single mutation tied to decreased susceptibility to HIV.

ViiV said that the findings support the future growth of VH499 as a prospective long-acting antiviral for HIV therapy. A Phase 1 study is evaluating long-acting versions of the capsid inhibitor. Findings from the investigations of VH499 and N6LS will guide the selection of the molecule to be combined with VH184.