Acceptance of Biologics License Application for Zevalin Radioimmunotherapy Announced by IDEC Pharmaceuticals

(BW HealthWire) — IDEC Pharmaceuticals Corporation (Nasdaq:IDPH) today announced that the Biologics License Application (BLA) for ZEVALIN(TM)(Ibritumomab Tiuxetan) has been accepted for filing by the U.S. Food and Drug Administration.

The action means that the FDA has determined that the submission contains sufficient information for the Agency to perform a meaningful review for marketing authorization.

The FDA has also approved IDEC’s request for priority review of the ZEVALIN BLA, meaning that the Agency’s review of the filing should be completed within six months of submission, although final approval, if at all, may require additional time. The company submitted the BLA to the FDA on November 1, 2000 for marketing approval. The proposed indication for ZEVALIN is for the treatment of low grade, follicular, CD20-positive transformed, relapsed or refractory, B-cell non-Hodgkin’s lymphoma (NHL) and Rituximab-refractory follicular NHL, which are cancers of the lymphatic system. If approved, ZEVALIN would be the first or one of the first radioimmunotherapies available for commercial use in the United States.

“We are very pleased that the ZEVALIN BLA has been accepted by the FDA,” said William H. Rastetter, chairman, chief executive officer and president of IDEC Pharmaceuticals. “This effort concludes years of hard work on the part of almost every IDEC employee. In the months ahead, we will continue to work closely with the FDA to facilitate the approval process.”

IDEC Pharmaceuticals focuses on the commercialization and development of targeted therapies for the treatment of cancer and autoimmune diseases. IDEC’s antibody products act chiefly through immune system mechanisms, exerting their effect by binding to specific, readily targeted immune cells in the patient’s blood or lymphatic systems. For a menu of IDEC’s current news releases and quarterly reports or to retrieve a specific release, call (888) 329-2309. On the Internet check the News Center at IDEC’s website: http://idecpharm.cdmail.biz.

The statements made in this press release contain certain forward-looking statements that involve a number of risks and uncertainties. Actual events or results may differ from IDEC’s expectations. For example, the timing, success and cost of preclinical research and clinical studies, the timing, acceptability and review periods for regulatory filings, the timing of and ability to obtain regulatory approval of products, such as ZEVALIN, the achievement of future product sales, the level of manufacturing performance and the risk factors listed from time to time in IDEC’s SEC filings including but not limited to its S-3 filed November 16, 2000, its Annual Report on Form 10-K for the year ended December 31, 1999 and Form 10-Q for the quarter ended September 30, 2000, may affect the actual results achieved by IDEC. These forward-looking statements represent the company’s judgment as of the date of this release. The company disclaims, however, any intent or obligation to update these forward-looking statements.

IDEC Pharmaceuticals and Rituxan are registered U.S. trademarks of the company. ZEVALIN is a trademark of the company. The company’s headquarters is located at 3030 Callan Road, San Diego, CA 92121.

IDEC Pharmaceuticals’ press releases are available at no charge through Business Wire’s News on Demand Plus. For a menu of IDEC’s current press releases and quarterly reports or to retrieve a specific release, call 888/329-2309. On the Internet, check the News Center at IDEC’s website http//idecpharm.cdmail.biz.

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CONTACT: IDEC Pharmaceuticals, San Diego