Gilead Sciences and Merck have announced positive results from a Phase 2 clinical trial evaluating a once-weekly oral combination of islatravir and lenacapavir for the treatment of HIV. The study demonstrated that the regimen maintained viral suppression in adults living with HIV after 48 weeks, suggesting it could become the first once-weekly oral treatment option for the disease.
The open-label study, presented at IDWeek, involved 104 virologically suppressed adults who were randomized to either the once-weekly regimen (n=52) or continued their daily Biktarvy regimen (n=52). The results showed that 94.2% of participants who switched to the weekly treatment maintained viral suppression, defined as HIV-1 RNA levels below 50 copies/mL. Notably, no participants in the weekly treatment group had detectable viral loads at the 48-week mark.
Efficacy and Safety
According to Jared Baeten, Gilead’s Senior Vice President of Virology, the study results are promising for maintaining viral suppression in individuals with HIV. He noted that the primary outcome at week 48 indicates that the regimen is poised to advance to Phase 3 trials. Secondary endpoints of the study showed comparable rates of viral suppression between the two groups, further supporting the efficacy of the investigational regimen.
Regarding safety, adverse events were reported in 19.2% of the islatravir-lenacapavir group, with the majority being mild, such as dry mouth and nausea. In comparison, only 5.8% of participants on Biktarvy reported treatment-related adverse events. No severe adverse events related to the study drugs were reported in either group. Baeten emphasized that the combination demonstrated a favorable safety and tolerability profile, further supporting its progression.
Future Development
The combination regimen is currently under further investigation in two Phase 3 studies to evaluate its safety and efficacy in a broader population of virologically suppressed individuals. Both islatravir and lenacapavir are investigational compounds, and ongoing studies are assessing their long-term potential as treatment options.
The collaboration between Gilead and Merck is crucial for the development and potential commercialization of this HIV treatment regimen. Baeten highlighted that both organizations are dedicated to advancing new and effective options for HIV treatment. With HIV continuing to pose public health challenges, these developments offer hope for more flexible and accessible treatment solutions for those living with the virus.
