GSK: HIV Presentation Highlights Long-Duration Dosing Options to Help Mitigate 2028 Patent Losses

GSK hosted an analyst presentation on its HIV segment (close to 20% of total sales) signaling increased focus on developing longer-duration therapies. While the updates don’t have an impact on our fair value estimate, the development of longer-duration treatments should help mitigate the 2028-29 patent losses on GSK’s key HIV drugs Tivicay, Triumeq, and Dovato (collectively representing close to 15% of total sales), which should reinforce the firm’s wide moat.

GSK’s strategy to extend its every-two-month HIV therapy Cabenuva/Apretude to longer duration should work well, given many patients’ preference for less-frequent dosing. The patents on Cabenuva/Apretude last until 2031 and beyond, offering a pathway to mitigate generic pressures on other older HIV drugs. In the PrEP setting (prophylaxis), GSK expects to launch four-month dosing of Apretude in 2026 followed by six-month dosing in 2028-30. We think these timelines are reasonable and the probability of success is high, given how well the drug has done in previous studies. However, Gilead’s competitive HIV drug Sunlenca should have six-month phase 3 PrEP data in 2024, potentially beating GSK to the market by several years.

In the treatment setting, GSK is also working to extend dosing of Cabenuva with a four-month dose expected to launch in 2027 followed by a six-month dose in 2028-30. The timeline for Sunlenca in this area is less clear, but the drug could be on a more similar timeline as Cabenuva in this setting, if ongoing early-stage combination trials are successful.

While Cabenuva/Apretude has already created a much larger dataset of successful clinical studies versus Sunlenca, if Sunlenca’s phase 3 studies are successful, its first-mover advantage with longer duration dosing will likely support the drug gaining the majority of new patients until GSK catches up.