Hepatitis C patients won another option to treat the dangerous liver disease Monday, as the Food and Drug administration approved a once-a-week drug called Peg-Intron .
Peg-Intron is a version of the longtime hepatitis treatment
interferon-alpha made with new "pegylation" technology that
cloaks it from the immune system so it stays active longer.
Manufacturer Schering-Plough Corp. said once-a-week injections
of Peg-Intron are about twice as effective as taking regular
interferon three times a week.
But there's a caveat: Today's top hepatitis C treatment is
another Schering drug called Rebetron, which combines interferon
with the medicine Ribavirin. The Food and Drug Administration
didn't approve combining Peg-Intron with Ribavirin.
Peg-Intron is administered subcutaneously once weekly for one year. The
dose should be administered on the same day of each week and may be
self-administered by patients.
"Chronic hepatitis C is one of the most prevalent and serious
public health problems in the United States," said Richard W. Zahn,
president of Schering Laboratories. "Peg-Intron offers convenient
once weekly dosing that may enhance patient compliance, an important
factor in determining optimal clinical outcome," Zahn said.
"While combination therapy with alpha interferon and ribavirin is
a recognized standard of care for chronic hepatitis C, Peg-Intron
monotherapy offers an alternative to patients in whom combination therapy
may be a contraindication or who are intolerant of this therapy,"
said John G. McHutchison, M.D., medical director, liver transplantation,
division of gastroenterology and hepatology, Scripps Clinic and Research
Foundation, La Jolla, Calif. "As the first pegylated interferon
product approved for marketing, Peg-Intron provides a valuable addition to
the therapies available to physicians for treating this serious
disease," McHutchison said.
The safety and efficacy of Peg-Intron has been demonstrated in a
randomized, controlled clinical study involving 1,219 adult patients with
chronic hepatitis C who were not previously treated with alpha interferon.
The study compared Peg-Intron (0.5, 1.0 or 1.5 mcg/kg) administered
subcutaneously once weekly to Schering-Plough’s INTRON A (interferon
alfa-2b, recombinant) Injection (3 MIU) administered subcutaneously three
times weekly. Patients were treated for 48 weeks and were followed for 24
weeks post-treatment. In the study, patients receiving the 1.0 mcg/kg dose
of Peg-Intron achieved a 24 percent treatment response rate of sustained
virologic response and ALT1 normalization as compared to a 12
percent treatment response rate in patients receiving INTRON A. The safety
and efficacy of Peg-Intron in combination with ribavirin have not been
Schering hasn't directly compared combination therapy to the new
drug. But some data suggest Rebetron may work somewhat better, said
Dr. Bill Schwieterman, FDA's hepatitis chief. On the other hand,
Peg-Intron may cause fewer side effects than combination therapy
because Ribavirin itself raises risks of hemolytic anemia, heart
dysfunction and other effects, he said.
"You have to weigh the benefits of not receiving the Ribavirin
versus the risk of having what appears to be a somewhat lesser
response rate with the Peg-Intron ," he explained.
Peg-Intron and regular interferon cause similar side effects,
including flu-like symptoms and depression. But Peg-Intron patients
are about 1 1/2 times more likely to have mild bone-marrow
suppression, Schwieterman said, something FDA suggested doctors