* Treatment combines VX-222, Incivek and 2 older drugs
* Half of patients on treatment rid of virus in 12 weeks
* Vertex shares fall 0.6 percent
(Adds analyst comment, safety details, background, updates
CHICAGO, July 26 As many as half of hepatitis C
patients in a small midstage trial who received a four-drug
combination, including two Vertex Pharmaceuticals (VRTX.O)
medicines, were able to stop treatment after just 12 weeks,
according to interim results from the study.
Vertex on Tuesday released preliminary results of the
trial, which added the company's experimental oral drug VX-222
to its recently approved Incivek pill and the traditional
standard treatments of pegylated interferon and ribaviron.
Interim results of the study, dubbed Zenith, showed that 50
percent of patients (15 of 30) who received the four-drug
combination including 400 milligrams of VX-222, were able to
stop all treatment at 12 weeks, and that 93 percent of those
patients had undetectable virus 12 weeks after treatment
Patients whose response did not make them eligible to halt
treatment at 12 weeks, received the two older drugs for another
12 weeks. Of those who continued in the trial, all 13 appeared
to be cured after 24 weeks of treatment, Vertex said.
"The patient numbers are relatively small in this study,
and the results incomplete, but they are more encouraging than
we would have expected," Sanford Bernstein analyst Geoffrey
Porges said in a research note.
However, Porges cautioned, "it is still too early to
declare that VX-222 is a viable drug deserving of significant
value in Vertex's stock price today. The tolerability and
safety will need to be established in much larger trials."
About 130 million to 170 million people worldwide are
chronically infected with hepatitis C virus, and more than
350,000 people die from hepatitis C-related liver diseases each
year, according to the World Health Organization.
Incivek is widely forecast to become a multibillion-dollar
seller and part of the new standard of care for the serious
liver disease. It, and a similar new drug from Merck & Co
(MRK.N) called Victrelis, are expected to transform treatment
for millions of patients by significantly raising cure rates,
while cutting the 48-week treatment regimen needed with the
older drugs by as much as half for many patients.
Researchers and several companies are hoping that
combination therapies with even newer drugs can further cut
treatment duration since interferon often causes flu-like
symptoms that leave patients feeling miserable.
With a combination that included 100 mg of VX-222 for 12
weeks, a sustained viral response was achieved by 82 percent of
patients, or nine of 11.
"The results from this study are the first to show the
potential for a combination of multiple direct-acting antiviral
medicines to help people with hepatitis C clear the virus with
as few as 12 and no more than 24 weeks of treatment," Robert
Kauffman, chief medical officer of Vertex, said in a
Patients in the study had the most common and more
difficult to treat genotype 1 form of the disease and had not
received prior treatment.
VX-222 belongs to a class of drugs called polymerase
inhibitors and works through a different mechanism than
Incivek, a protease inhibitor that directly blocks an enzyme
essential for viral replication.
The most common side effects from the four-drug regimen
were fatigue, nausea, diarrhea, anemia, itchiness and rash. Six
patients discontinued treatment because of adverse reactions.
JPMorgan analyst Geoff Meacham called the preliminary
safety profile "encouraging," noting no cases of kidney failure
or severe diarrhea.
Vertex shares were down 28 cents, or 0.6 percent, at $49.17
in midday trading on the Nasdaq.
The company is due to report second-quarter results on
Thursday, including the first few weeks of sales of Incivek,
its first commercial product.
(Reporting by Susan Kelly; additional reporting by Bill
Berkrot in New York; Editing by Gerald E. McCormick, Derek
Caney and Steve Orlofsky)