To put the Abbott results released Monday in perspective, consider that hepatitis C cure rates for treatment-naive patients have risen from approximately 45% with long-acting interferon and ribavirin to 75-80% when
(VRTX - Get Report)
Incivek is added to interferon/ribavirin.
The Abbott data in null responders is even more dramatic given that only about 5% of these hard-to-treat patients were cured by interferon and ribavirin alone. Adding Vertex's Incivek increased null responder cure rates to about 30%.
Among more recent all-oral hepatitis C regimens currently being studied, a combination of
(BMY - Get Report)
daclatasvir plus Gilead's GS-7997 dosed for 24 weeks achieved an
SVR4 rate of 100%
in genotype 1, treatment-naive patients. Bristol may present updated SVR12 cure rates from this very promising regimen at the AASLD meeting, but future studies are not planned because
Gilead refused to cooperate
Instead, Gilead is pushing ahead with its own, all-oral regimen consisting of 12 weeks of GS-7977, GS-5885 (a NS5A inhibitor just like Bristol's daclatasvir) with and without ribavirin. Early SVR4 cure data in treatment-naive patients may be announced today but certainly at the AASLD meeting.
Gilead has already starting enrolling patients in phase III studies that could see its hepatitis C regimens approved late next year. Abbott's
phase III studies have not opened for patient enrollment
, which means approval may not come until late 2014.
Gilead's other advantage is convenience. The GS-7977/GS-5885 regimen is being co-formulated into a single, once-daily pill. Abbott's combination regimen consists of pills that must be taken either once a day or twice a day, making compliance more complicated.
-- Reported by Adam Feuerstein in Boston.