GSK's Dovato Matches Gilead's Biktarvy with Less Weight Gain in Spanish Study

Gilead Sciences' leading HIV treatment drug, Biktarvy, has set a high standard in the field. A recent study named PASO DOBLE has revealed that GlaxoSmithKline’s (GSK) two-drug regimen, Dovato, demonstrates similar effectiveness to Gilead's three-drug formula in managing HIV.

The Phase 4 trial took place across 30 research centers in Spain and included 553 patients who had successfully suppressed HIV. The findings indicated that after 48 weeks, both Dovato and Biktarvy were effective in maintaining viral suppression. Specifically, 2.2% of the 277 patients on Dovato had viral RNA levels rising to 50 copies/ml or more, whereas only 0.7% of the 276 patients on Biktarvy experienced this increase. This 1.4% difference met the pre-determined non-inferiority margin of 4%.

An important secondary outcome revealed that patients on Biktarvy experienced significantly more weight gain compared to those on Dovato. Over the 48-week period, the average weight increase in the Biktarvy group was 1.81 kg, whereas it was 0.89 kg in the Dovato group. Additionally, 29.9% of patients using Biktarvy had more than a 5% weight gain, compared to 20% in the Dovato group. This trend was especially noticeable among patients transitioning from tenofovir disoproxil fumarate (TDF) regimens.

Harmony Garges, chief medical officer of ViiV Healthcare at GSK, highlighted the significance of these findings, noting that weight gain is a prevalent concern among individuals living with HIV. Weight gain is a recognized side effect of certain HIV medications, including integrase inhibitors present in both Dovato and Biktarvy. The use of TAF can also contribute to weight gain, suggesting a combined mechanism might be responsible for the increased weight observed.

Lead researcher Dr. Esteban Martinez noted the significance of these findings, emphasizing the need to examine the broader impacts of HIV treatments beyond viral suppression, such as weight gain. He stressed that as HIV drugs become more effective, the focus is shifting toward minimizing side effects and reducing administration frequency. GSK's Dovato aims to decrease long-term toxicity by using a two-drug formula, marking a step in this direction.

The competition between GSK and Gilead is intensifying, particularly in the development of long-acting therapies based on dual-drug formulations. GSK's Cabenuva, a bimonthly injection, has gained some acceptance, but the company acknowledges the need for longer dosing intervals to achieve a substantial impact. Gilead has a slight advantage in this domain with the launch of Sunlenca, a biannual drug, and is actively working on comprehensive therapies utilizing capsid protein inhibitors.

As the landscape of HIV treatment continues to evolve, both companies are striving to balance efficacy with patient quality of life, focusing on reducing side effects and improving the convenience of drug administration. The results of the PASO DOBLE study provide important insights into the future direction of HIV treatment strategies.