By Mary Welch
Schering-Plough Corp. advanced Enzon Inc.'s longer-acting formulation of its Intron A (interferon alfa-2b) into Phase III trials for malignant melanoma.
The drug, known as PEG-Intron A, conjugates the original agent to polyethylene glycol. It is already in the late stage of Phase III trials for hepatitis C and in early phase trials for chronic myelogenous leukemia and solid tumors, as well as in combination with Rebetol for hepatitis C.
Kenneth Zuerblis, chief financial officer and vice president of financing for Piscataway, N.J.-based Enzon, said the deal with Schering-Plough, of Madison, N.J., does not provide for more money as a result of the melanoma Phase III study.
"The deal calls for $2.5 million for the first compound to reach Phase III, which we did with PEG-Intron A for hepatitis C," said Zuerblis. "We get another $1 million when we file our first new drug application, and $2 million upon approval."
Intron A was modified using Enzon's Pegnology drug delivery technology, which is designed to reduce immunogenic reactions to therapeutic proteins and enable them to remain in the bloodstream longer.
Enzon is able to disguise a drug from the immune system, preventing antibodies from binding to the protein molecule and lowering its immunogenic potential. Protein drugs that are not PEG-modified are frequently vulnerable to the immune system, which recognizes the molecules as foreign. (See BioWorld Today, June 29, 1998, p. 1.)
Ron Asinari, spokesman for Schering-Plough, said no information would be disclosed about dosage, endpoints or participants in the melanoma trials.
The two companies entered their product development and licensing agreement in November 1990, and the deal was revised in 1995.
Intron A, marketed in 82 countries for 16 major indications, was licensed to Schering-Plough from Biogen Inc., of Cambridge, Mass. Alpha interferon was the subject of a patent infringement lawsuit involving Biogen; Schering-Plough; Hoffmann La-Roche Ltd., of Basel, Switzerland; and Genentech Inc., of South San Francisco. The litigation was settled earlier this year. (See BioWorld Today, June 22, 1998, p. 1.)
Enzon's stock (NASDAQ:ENZN) closed Monday at $6.25, up $0.437. *