By Mary Welch

As Schering-Plough Corp. disclosed six-year follow-up results from a Phase III trial of Intron A for follicular lymphoma in chemotherapy patients, the FDA approved the drug as a treatment for hepatitis B in pediatric subjects.

As a result of the FDA approval, Intron A (interferon alfa-2b), the only interferon marketed in the U.S. for chronic hepatitis B in adults, may be sold for use in patients from 1 to 19 years old.

Ronald Asinari, spokesman for Madison, N.J.-based Schering-Plough, did not disclose an estimate of market size for the pediatric indication, but the Centers for Disease Control reported 1,200 new cases of hepatitis B in the 1-to-19 age group in 1994.

For pediatric patients, the benefit of Intron A was proven in a 149-patient trial in 1-to-17-year-old subjects. All but one of the treated responders showed positive results 12 to 24 months after treatment.

In the Phase III follow-up for advanced-stage follicular lymphoma patients, patients treated with chemotherapy and Intron A showed a significantly longer median overall survival than those treated with chemotherapy alone.

Thirty to 40 percent of all non-Hodgkin's lymphoma cases have follicular lymphoma. Each year, about 54,000 new cases of non-Hodgkin's lymphoma are diagnosed, making it the sixth most common cancer in the U.S., and one of the most rapidly increasing cancers.

Sales On Track To Hit $600M This Year

Schering-Plough did not disclose the planned filing date for regulatory approval in the lymphoma indication.

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; Hoffman 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.)

The drug is used in treating chronic hepatitis C in adults, hairy cell leukemia, AIDS-related Kaposi's sarcoma, and venereal warts. Marketed in the U.S. in combination with Rebetol (ribavarin) as Rebetron Combination Therapy for hepatitis C, it is also an adjuvant therapy for malignant melanoma and is used in combination with chemotherapy for non-Hodgkin's lymphoma. Rebetron was approved by the FDA in June. (See BioWorld Today, June 4, 1998, p. 1.)

Last year, Intron A posted worldwide sales of $598 million, with $231 million of that amount coming from the U.S. In the first six months of this year, worldwide sales reached $300 million, of which about $124 million was sold in the U.S.

Schering-Plough's stock (NYSE:SGP) closed Tuesday at $102.125, up $1.875. *