ViiV Healthcare and Shionogi have presented promising initial late-stage data which suggests that dolutegavir is superior to Gilead Sciences' big-selling Atripla as a treatment for HIV.

ViiV, a joint venture between GlaxoSmithKline and Pfizer. and the Japanese drugmaker, noted at 48 weeks, 88% of study participants on the dolutegravir regimen were virologically suppressed versus 81% on Atripla (efavirenz/emtricitabine/tenofovir)  However, ViiV and Shionogi said that differences in efficacy were primarily driven by a higher rate of discontinuation due to adverse events on the Atripla arm.

Tsutae Nagata, chief medical officer at Shionogi,said that taken together with the results of an earlier trial (called SPRING-2), the latest findings "suggest that, if approved by regulators, a treatment regimen containing dolutegravir may offer people living with HIV an important additional first line option in the future". His counterpart at ViiV, John Pottage, added that the study represents "an important milestone in the development of dolutegravir-based regimens, including a single-tablet regimen".

He went on to say that the firms are awaiting further safety and efficacy data from two Phase III studies in treatment-experienced patients "to continue to build a comprehensive picture of the role of dolutegravir". Full results of the study, the second of four Phase III trials, will be presented at upcoming scientific meetings.