GSK's once-monthly HIV treatment proves trial success

GlaxoSmithKline has seen positive results from clinical trials of its once-monthly injectable treatment for HIV.

GSK's ViiV Healthcare subsidiary's global, phase III 'Atlas' study showed a two-drug regime, cabotegravir and rilpivirine, injected once a month had similar efficacy to a standard daily, oral three-drug regimen after 48 weeks of treatment.

The drug combination, which is being co-developed as part of a collaboration with Janssen Sciences, is not approved by regulatory authorities anywhere in the world.

The Atlas trial was designed to establish if HIV-1-infected adults who had maintained viral suppression for at least six months, on a daily oral regimen comprised of two nucleoside reverse transcriptase inhibitors (NRTIs) plus a third agent, maintained similar rates of viral suppression upon switching from the three-drug oral regime to the investigational, two-drug, long-acting, injectable treatment.

Results showed the two-drug injectable option met the primary endpoint for non-inferiority in terms of viral loads in the blood, while overall safety, virologic response and drug resistance results for the injectable regimen were also consistent with results from the phase II studies.

Headline results from a second trial of the same two-drug regimen, but in treatment-naïve individuals, are expected later this year.

ViiV chief scientific and medical officer John Pottage said: "If approved, this regimen would give people living with HIV one month between each dose of antiretroviral therapy, changing HIV treatment from 365 dosing days per year, to just 12."

ViiV is majority owned by GSK, with minority stakes owned by Pfizer and Shionogi.