Schering-Plough Corp. and Enzon Inc. have won U.S. Food and Drug Administration approval to sell Peg-Intron, a hepatitis C drug that analysts say could have more than $2 billion in annual sales.
The injectable drug is a once-weekly version of Schering-Plough's Intron A, the world's top-selling hepatitis medication, and is considered by analysts to be key to increased sales for Schering-Plough over the next five years.
While the FDA approved Peg-Intron for use on its own, analysts say the drug will mainly be used with another drug, Costa Mesa-based ICN Pharmaceuticals Inc.'s ribavirin.
The top hepatitis C treatment, also sold by Schering-Plough, is a combination of Intron A and ribavirin that's marketed as Rebetron. The combination treatment is significantly more effective against hepatitis C than Intron A alone, and recent studies have suggested the combination of Peg-Intron and ribavirin works better than either Rebetron or Peg-Intron alone.
Data on the combination of Peg-Intron and ribavirin was so compelling that some doctors appear to be waiting for the improved combination before treating newly diagnosed patients, prompting ICN last week to warn that earnings for 2000 were less than expected.
"They've presented the data publicly and it was very good--and it's because it was so good that doctors are waiting," said Carl Seiden, an analyst with J.P. Morgan Chase & Co. "There is really a growing body of evidence that doctors are delaying treatment. . . . Their sales of [Rebetron] appear to be suffering in the near term."
Schering-Plough is expected to seek FDA approval for the combination using Peg-Intron later this year. The company has already filed an FDA application to sell ribavirin on its own, which would enable doctors to combine it with Peg-Intron if they choose.
Hepatitis C affects about 4 million people in the U.S.