Patent settlement clears legal path for MR agent

Sterling Winthrop cleared a major obstacle to the marketing ofits MRI contrast agent Omniscan this month, with the settlementof a patent infringement suit filed by Schering.

Sterling has licensed U.S. rights to the nonionic gadoliniumcontrast agent from Nycomed of Oslo. Omniscan is currently underreview by the Food and Drug Administration.

Germany's Schering filed suit against Sterling in February,claiming that Omniscan infringed on patents Schering holds forMagnevist, the only MRI agent approved by the FDA (SCAN 7/29/92).Magnevist is marketed in the U.S. by Berlex, a Schering subsidiary.

Sterling, Nycomed and Schering announced on Aug. 11 that theyhad reached an agreement settling the legal action. In exchangefor dropping its patent claim, Schering will receive a cash paymentof an undisclosed amount, as well as options for marketing rightson MRI contrast agents being developed by Sterling and Nycomed.Specifics of those agents were not disclosed in the announcement.

Representatives of both sides claimed victory with the resolutionof the dispute. Schering strengthens the number of products inits research and development pipeline, while Sterling will havea free hand to market Omniscan, pending FDA approval.

"Omniscan is under review for approval, and it's best tohave that approval and launch unencumbered," said Terry Kelley,a Sterling spokesperson. Sterling expects FDA approval of Omniscanby the end of this year, he said.

Schering reached an agreement late last year with Bristol-MyersSquibb on Prohance, another gadolinium-based contrast agent awaitingFDA approval. In that deal, Schering received U.S. marketing rightsto Squibb's antiarrhythmic agent Betapace in exchange for allowingProhance to go forward.

Schering's confidence in the continued strength of Magnevistwas a major factor in its decision to reach agreements that clearthe way for competing products in the contrast agent market, accordingto Wendy Neininger, a Schering spokesperson.

"We feel positive that Magnevist is a very strong product,"Neininger said. "It has a strong safety and efficacy recordand we think we will continue to retain the customer base we have."