Schering-Plough Corp. said Thursday that U.S. regulators agreed to let it sell the antiviral drug Rebetol as an individual treatment for the liver disease hepatitis C, a decision long awaited by patients seeking a more effective way to use the medicine.
Rebetol capsules, which are made by ICN Pharmaceuticals Inc. in Costa Mesa, have been available only in a combination package with a Schering-Plough injectable interferon drug. The packages, marketed under the brand name Rebetron, are the Kenilworth, N.J., firm's second-biggest product and have been considered the gold standard of treatment.
Doctors, though, have recently held off on prescribing Rebetron, waiting for the chance to write separate prescriptions for Rebetol and Schering-Plough's new and longer-acting form of interferon called Peg-Intron, which the company sells as a treatment for chronic hepatitis C.
The Food and Drug Administration might rule as early as next month on the application to market Rebetol and Peg-Intron together.
"The approval today gives us more hope they'll get the Peg-Intron approval in early August," said analyst Kenneth Nover at A.G. Edwards & Sons Inc., who estimated the combination could have U.S. sales of $2 billion a year.
Doctors may begin to prescribe Rebetol with Peg-Intron, some analysts said, though the FDA approval permits Schering-Plough to market Rebetol capsules for use only with Intron-A.
"Doctors are allowed to prescribe any drug for any purpose, within reason, so they don't have to wait for FDA approval" to combine Rebetol and Peg-Intron, Nover said. "Doctors know there's clinical data to show Peg-Intron with Rebetol works best of all to treat hepatitis."
Richard Evans, a Sanford Bernstein drug analyst, estimated that 100,000 Americans have had unsuccessful interferon therapy for hepatitis C and that at least 75,000 of them will now begin taking the improved Schering-Plough combination therapy over the next four years.
"The demand is substantial and will be a profit driver for Schering-Plough in the fourth quarter and into 2002 and 2003," Evans said.
Sales will skyrocket, he said, despite expected competition from a similar interferon using the PEG technology that has been developed by Swiss drug maker Roche Holding Ltd.
Roche expects FDA approval for its competing product, Pegasys, by early next year. Evans said the drug will probably be as effective and safe as Peg-Intron.
Schering-Plough licenses Peg-Intron from biotechnology company Enzon Inc., which helped develop the drug.
Both ICN's and Enzon's stock rose solidly. ICN's stock rose $2.03 a share, or 7%, to $30.93 a share on the New York Stock Exchange, and Enzon's stock shot up $7.02, or 12%, to $62 a share on Nasdaq. Schering-Plough gained 80 cents to close at $38 a share, also on the New York Stock Exchange.
Bloomberg News and Reuters were used in compiling this report.