Reuters (04.19.12) - Friday, April 20, 2012
New results from a clinical study of a hepatitis C treatment
combining Gilead Sciences Inc.'s GS-7977 with Bristol-Myers
Squibb (BMS) Co.'s daclatasvir showed a 100 percent response
rate in treatment-naive patients with the most common, and
difficult to treat, form of the virus. Interim data from the
mid-stage trial were presented Thursday at the International
Liver Congress 2012 in Barcelona.
GS-7977 is a nucleotide polymerase inhibitor. Daclatasvir is
an NS5A inhibitor, a new drug class. Both are designed to
block enzymes hepatitis C needs to replicate. Neither
interferon, an injected drug known to cause significant side
effects, nor ribavirin - an older, common antiviral, was used
in the combination.
All 44 study patients with hepatitis C genotype 1 had
undetectable levels of the virus in their blood four weeks
post-treatment, compared to 40 of 44 patients with genotypes 2
or 3. Cured patients are considered those who still have
undetectable levels 12 weeks following treatment's end; a
sustained viral response at four weeks is considered to be a
fairly accurate predictor of cure. Complete trial results are
expected later this year.
The combination was found to be well tolerated, with side
effects including fatigue, headache, and nausea. Reasons for
two patients leaving the study are not believed to be due to
the drugs, BMS said.
Despite the impressive data, BMS spokesperson Cristi Barnett
said Gilead is "not interested" in a phase III collaboration.
Gilead is set to start a trial of GS-7977 with its own
experimental NS5A inhibitor, while BMS is testing daclatasvir
with a drug similar to GS-7977.