ViiV Healthcare has unveiled encouraging mid-stage data backing a long-acting formulation of its two-drug regimen cabotegravir and rilpivirine for the treatment of HIV

According to long-term data from the Phase II LATTE-2 trial, the injectable regimen - administered either every eight weeks or every four weeks - showed "high rates of virologic response, long-term durability of virologic response and good overall tolerability," the firm noted.

At 160 weeks, 90% and 83% of the patients receiving the injectable cabotegravir/rilpivirine every eight and four weeks, respectively, remained virally suppressed.

Of the patients on the oral comparator arm who elected to switch to the injectable regimen at Week 96, 97% and 100% remained virally suppressed on every eight- and four-week dosing schedule, respectively, at Week 160.

The firm did note that through Week 48, two patients developed protocol-defined virologic failure (PVDF) on the every-eight-week dosing arm, one with treatment-emergent, non-nucleoside reverse transcriptase inhibitor and integrase inhibitor resistance. However, no additional PVDF cases were observed on any arm between Week 48 and Week 160.

"The LATTE-2, three-year data show cabotegravir and rilpivirine as a long-acting injectable regimen may provide an alternative to daily pills, reducing the number of annual doses from 365 to 12. It is encouraging to see these long-term results," noted John Pottage, chief scientific and medical officer at ViiV Healthcare.

The long-acting regimen of cabotegravir and rilpivirine is also being investigated in three Phase III studies: FLAIR, ATLAS and ATLAS-2M. The ATLAS studies are evaluating the safety and efficacy of the four-week and eight-week dosing regimen in people living with HIV who are suppressed on any three-drug oral regimen with two NRTIs, while FLAIR is looking at people living with HIV who are suppressed on Triumeq (DTG/ABC/3TC).