Gilead Sciences, Inc. ( GILD ) recently announced encouraging 48-week data from a phase II study (study 102) on its HIV single tablet regimen (STR). The STR includes tenofovir alafenamide (TAF), a pro drug of Gilead's HIV drug Viread. The randomized, double-blind study compared the safety and efficacy of a once-daily STR of TAF 10 mg, elvitegravir 150 mg, cobicistat 150 mg and Emtriva 200 mg with Stribild.
We remind investors that Gilead gained approval from the U.S. Food and Drug Administration (FDA) for Stribild in Aug 2012 as a first-line therapy for treating adults with HIV-1 infection. European approval came in May 2013.
Stribild is a combination of elvitegravir, cobicistat and Truvada. We note that Truvada itself is a combination of Viread and Emtriva. Data from the above study revealed that the TAF-based regimen worked as effectively as Stribild for treating treatment-naïve HIV infected adults. Moreover, the candidate was found to be safe in the study.
We are impressed with the encouraging data on the HIV candidate. Successful development and commercialization of the TAF-based regimen would further strengthen its HIV portfolio.
Although pleased with the progress of the TAF-based regimen, we believe that investor focus will remain on sofosbuvir, which is being developed for treating patients suffering from chronic hepatitis C virus (HCV). The HCV candidate is under priority review in the U.S. (target date: Dec 8, 2013). Sofosbuvir is also under review in the EU. Gilead is also seeking approval for the candidate in other countries such as Canada, Switzerland, Turkey and Australia.
Approval of sofosbuvir would not only boost Gilead's top line but also strengthen its position in the lucrative HCV market. A sizeable population suffers from HCV globally. However, the treated population is much lower, thus leaving the field open for new treatments.