SCHERING 1990 INTRON A SALES SHOULD COMFORTABLY EXCEED $150 MIL.; FUTURE PEG-ged TO ENZON FORMULATION; EULEXIN (FLUTAMIDE) SALES WILL TOP $100 MIL.

Sales estimates of more than $150 mil. in 1990 for Schering-Plough's Intron A may be an underestimate, the company indicated Nov. 14. Sales of alfa-2b interferon, which is prescribed for 16 diseases in 43 markets worldwide, were $90 mil. in 1989. The product is approved in 57 countries. President Dick Kogan, speaking to financial analysts at the company's annual R&D update in Kenilworth, N.J., said "we have absolutely no trouble" with industry forecasts for Intron A sales of more than $150 mil. this year. Calling Intron A's market performance "exceptional," Kogan expressed Schering's high hopes for the product when he said "we've taken to calling it a 'new drug for the next 10 years.'" The product is already approved in the U.S. for the treatment of Kaposi's sarcoma, veneral warts and hairy cell leukemia. Roche's alpha interferon product Roferon is marketed in the U.S. for Kaposi's and veneral warts. Schering is also "very optimistic," Kogan said, about Intron A's approval in the U.S. as a treatment for hepatitis C and in the future for chronic hepatitis B. A PLA for the chronic hepatitis B indication was filed in September 1989. Intron A was recommended for approval for non-A, non-B hepatitis by FDA's Biological Response Modifiers Advisory Committee on July 30. Three days later, The New England Journal of Medicine published a very favorable Intron A study that found a 36% remission rate in patients with chronic hepatitis B ("The Pink Sheet" Aug. 6, p. 11 and p. 12). Schering and PEGnology company Enzon announced a definitive co-development agreement Nov. 15 to develop a longer-acting form of Intron A using Enzon's protein-based polyethylene glycol (PEG) drug delivery system. The letter-of-intent-stage agreement was reached last spring ("The Pink Sheet" April 9, In Brief). Enzon is in the process of scaling-up manufacturing for PEG-ged Intron A and preclinicals are under way. The South Plainfield, N.J.-based firm will receive milestone payments of $6 mil. Schering will conduct and fund the clinicals, file for regulatory approval and have worldwide marketing rights to the PEG-ged product. Enzon retains worldwide rights to manufacture the bulk product and will receive royalties on global sales. Sales of Schering's other major cancer therapy, Eulexin (flutamide) for advanced prostate cancer, are expected to reach$100 mil. in 1990. The product, approved in January 1989 as a concomitant treatment with Abbott/Takeda's Lupron, is also being studied in early stage prostate cancer and benign prostatic hypertrophy, Kogan announced. Eulexin has been on the market overseas since 1983. Commenting on the absence of the Schering/Sandoz granulocyte macrophage-colony stimulating factor (Leucomax) on an upcoming FDA advisory committee agenda, Schering Chairman Robert Luciano said the schedule was a "disappointment to us -- but hardly fatal." The Dec. 13-14 FDA Biological Response Modifiers Advisory Committee agenda covers Amgen's G-CSF and Immunex's GM-CSF products. Luciano added: "We have closed the gap [in PLA filing delays compared to the other CSFs] and we will not suffer a material competitive disadvantage by missing the December session." Schering filed the Leucomax PLA on Jan. 31. The company has not revealed the indications that it is seeking, only that it is for patients with low white cell counts. Sandoz, which licensed the product from Genetics Institute, will co-market the product in the U.S. Kogan commented that the CSF market has been estimated at "anywhere from $200 mil. to $800 mil. That's a pretty big ballpark and, although this is a very competitive field, we will capture a good portion of this market."