In a move that counters some of August’s product offloading, GlaxoSmithKline announced Sunday that it was increasing its financial stake in an experimental AIDS treatment it developed with Shionogi and Pfizer.

Under the new deal, Shinogi gets at 10% stake in ViiV Healthcare, the GSK/Pfizer HIV collaboration, and space on Viiv’s Board of Directors. The company will also “continue to have ongoing involvement in the formulation of the development and commercialization plans for the integrase inhibitor portfolio” as well as royalty payments, said GSK. Glaxo and Pfizer created ViiV in 2009 when the two companies merged their HIV businesses. At the time, the split was 85% GSK, 15% Pfizer. As of October 31, the ViiV split will be 76.5% GSK, 13.5% Pfizer and 10% Shionogi. In exchange, ViiV gets global rights to the integrase portfolio, which includes the Phase III, once-a-day dolutegravir. According to Reuters, this shift boosts GSK’s financial interest in the drug to between 60% and 66%, compared to the 40% stake it had in dolutegravir under the previous agreement. 

Integrase inhibitors interfere with the virus’ ability to be encoded into a cell’s DNA. Merck’s Insentress is an integrase inhibitor, as is Gilead’s Gilead’s elvitegravir, which is part of the FDA-approved Quad pill.

ViiV Chair David Redfern said in a statement that the deal will help streamline R&D and help avoid duplicative efforts. Redfern also noted the timing – the deal closes just before the the end of the year, by which time it expects to file the drug for regulatory review.