ViiV Healthcare’s first-in-class attachment inhibitor fostemsavir has shown promise as a treatment for heavily pre-treated HIV patients failing on current antiretroviral regimens.

According to data from the BRIGHTE study, fostemsavir, in combination with optimised background treatment (OBT), maintained virologic suppression from Week 24 to Week 48 in this “difficult-to-treat” population.

Results showed that 54% of patients in the randomised cohort achieved virologic suppression (<40 copies/mL) at 48 weeks of treatment with fostemsavir plus optimised background therapy, and also showed immunologic improvement, the firm noted.

On the safety side, most patients who received fostemsavir experienced at least one adverse event (AE) by week 48, the most commonly reported being diarrhoea, nausea and headache.

Thirty-five percent of participants had one or more serious adverse events, most commonly related to infections, and these occurred in the most immunocompromised patients.

John Pottage, chief scientific and medical officer of ViiV, which is majority owned by GSK, said the firm is excited by the results of the study.

“People living with HIV who participated in this study were failing on their current antiretroviral regimens and had few treatment options left available to them; we were encouraged to see that treatment with fostemsavir resulted in both meaningful reductions in viral load and improvements in the health of their immune systems.”

ViiV acquired rights to fostemsavir through its acquisition of Bristol-Myers Squibb’s HIV assets in 2016.