By Randall Osborne

West Coast Editor

Hoffmann-La Roche submitted a biologics license application (BLA) for Pegasys (peginterferon alfa-2a) as a treatment for chronic hepatitis C in non-cirrhotic and cirrhotic patients with compensated liver disease.

Data showing efficacy of the drug, which is made with polyethylene glycol (¿peg¿) licensed from Huntsville, Ala.-based Shearwater Polymers Inc., show particularly good results in cirrhotic patients, said Kellie McLaughlin, spokeswoman for Hoffmann-La Roche, of Nutley, N.J.

¿They¿re the toughest hepatitis C patients to treat, and we have about a 30 percent efficacy rate that we¿re really proud of,¿ she said.

A ready-to-use solution, Pegasys would be administered as a once-weekly subcutaneous injection taken for one year. Standard interferon must be taken three times per week.

In pegylation, one or more chains of polyethylene glycol are attached to the interferon molecule to provide a protective barrier that keeps the interferon from being eliminated too quickly, while not significantly reducing the binding site selectivity.

Effectiveness relates partly to the length of the chain, McLaughlin said.

¿Roche has been doing pegylation research for a long time,¿ she said. ¿[Scientists] came up with what they considered the optimal size. It has to do with where the [polyethylene glycol] attaches to the interferon protein, and how the strands interact with each other.¿

In December, Madison, N.J.-based Schering-Plough Corp. filed a BLA for its PEG-Intron powder for injection for the treatment of chronic hepatitis C. PEG-Intron is a modified form of Schering-Plough¿s billion dollar drug, Intron A (interferon alfa-2b), and uses polyethylene glycol technology designed by Enzon Inc., of Piscataway, N.J. (See BioWorld Today, Jan. 6, 2000, p. 1.)

Although Pegasys and PEG-Intron are interferons tested as once-weekly injections, the two drugs ¿are not the same,¿ McLaughlin said. ¿They¿re different in many ways, but we haven¿t done a head-to-head study, so you can¿t really make a comparison.¿