has received a US license for its direct-acting antiviral combination of
grazoprevir and elbasvir, to be marketed as Zepatier. The combination of grazoprevir (an HCV
protease inhibitor) and elbasvir (an NS5A inhibitor) is dosed once daily for 12
weeks or 16 weeks with or without ribavirin.
The combination has been approved for the treatment of
genotypes 1 and 4. Approval is based on results of studies in previously
untreated and treatment-experienced
patients. It has not been approved for use in people with moderate or
severe hepatic impairment (Child Pugh B or C stages).
A 12-week treatment course is recommended for all patients
apart from those with genotype 4 who have previous experience of pegylated
interferon and ribavirin, or people with genotype 1a and baseline NS5A mutations
indicating possible resistance to NS5A inhibitors. These groups of patients
should receive a 16-week course of treatment.
Use in combination with ribavirin is recommended for the
following groups of people:
- Genotype 1a: previously untreated people and
people previously treated with pegylated interferon and ribavirin if they have
baseline NS5A mutations indicating possible resistance to NS5A inhibitors
- Genotype 1a and 1b: people previously treated
with pegylated interferon, ribavirin and a protease inhibitor (boceprevir,
simeprevir or telaprevir)
- Genotype 4: people previously treated with
pegylated interferon and ribavirin.
Testing for NS5A resistance-associated polymorphisms
(positions 28, 30, 31 or 93) is recommended for GT1a-infected patients prior to
Merck has priced its regimen at a list price of $54,600, significantly
below the list price established for its chief competitor product, Gilead’s
Merck’s price compares with a list price of $94,500 for Harvoni in the United
States, although Gilead is believed to have agreed discounts of up to 30% with
The European Medicines Agency is reviewing a licensing
application for the combination and a decision is expected in 2016.