Shionogi-ViiV Healthcare LLC announced that initial results from its Phase 3 study SINGLE (ING114467) show superiority of its investigational HIV medication dolutegravir plus Epzicom over Atripla, one of the most widely prescribed antiviral medications in the country. At 48 weeks, 88% of study participants on the dolutegravir regimen achieved undetectable viral load (less than 50 copies/mL) vs. 81% of those on Atripla, a statistically significant difference. The company said the difference was primarily driven by a higher rate of discontinuation due to adverse events in the Atripla arm. All individuals in the study were taking antiviral therapy for the first time, a group that does the best in HIV treatment. There were 414 individuals put on dolutegravir and 419 put on Atripla. Overall, 2% of those on the dolutegravir-based regimen discontinued due to adverse events vs. 10% of those receiving the Atripla regimen. The most common adverse events while on Atripla were neurological (reported by 41% of Atripla recipients vs. 15% of participants receiving the dolutegravir), while the most common drug-related adverse events with dolutegravir were in the gastrointestinal system (reported by 22% of people on dolutegravir vs. 22% of those given Atripla).
Dolutegravir is an investigational integrase inhibitor (INSTI), the same class as Isentress, the only INSTI currently on the market.