IDEC Pharmaceuticals to Respond Promptly to FDA’s Complete Review Letter for ZEVALIN Radioimmunotherapy BLA

(BW HealthWire) — IDEC Pharmaceuticals Corporation (Nasdaq: IDPH) today announced it will promptly submit additional information and analysis to the U.S. Food and Drug Administration (FDA) in response to the recently received Complete Review Letter from the FDA, Center for Biologics Evaluation and Research (CBER), regarding the company’s Biologics License Application (BLA) for ZEVALIN(TM) (Ibritumomab Tiuxetan) radioimmunotherapy.

The company is seeking marketing approval of ZEVALIN for the treatment of low grade, follicular, CD20-positive transformed, relapsed or refractory, B-cell non-Hodgkin’s lymphoma (NHL) and Rituxan(R) (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.

The information requested by the FDA is related to two areas: (i) clinical and (ii) chemistry, manufacturing and controls (CMC). Importantly, based on IDEC’s review of the Complete Review Letter and subsequent discussions with the agency, the company believes it can address all of the agency’s open issues in a responsive and comprehensive manner without the need to conduct any new or additional clinical trials prior to the completion of the BLA review by the agency. The company is working expeditiously to compile the information and expects to submit its response documentation and analysis by mid-July 2001. The FDA will establish an independent schedule for pre-approval inspection of the company’s ZEVALIN contract suppliers.

“The July timeline for response is made possible by the positive dialogue we have had with the FDA over the last several months,” said William H. Rastetter, Ph.D., chairman, chief executive officer and president of IDEC Pharmaceuticals. “With this open and ongoing dialogue, we have been able, early on, to initiate data collection and analysis on a number of the agency’s open questions. As we did in 1997 with the request for additional information for our Rituxan BLA, the IDEC team has diligently tackled this aspect of the drug development process and has begun preparation of comprehensive responses to the FDA’s recent requests on the ZEVALIN filing.”

The FDA accepted the ZEVALIN BLA for filing in December 2000, assigning it to a six-month priority review. Issuance of the Complete Review Letter satisfies the FDA’s performance goal for priority review under the Prescription Drug User Fee Act (PDUFA). IDEC’s partner, Schering A.G., which has marketing rights to ZEVALIN outside the United States, had its Marketing Authorization Application (MAA) for ZEVALIN accepted for review by the European Medicines Evaluation Agency (EMEA) in January 2001.

As previously announced, interested parties can access a live webcast of the company’s overview of the ZEVALIN Complete Review Letter and the company’s strategy for response to the agency through a link at IDEC’s website ( The webcast will begin today at 1:30 Pacific Daylight Time and will remain available for replay until close of business on Monday, May 14, 2001.

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:

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, 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 Annual Report on Form 10-K for the year ended December 31, 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, which has headquarters at 3030 Callan Road, San Diego, CA 92121, is a member of the NASDAQ 100.

CONTACT: IDEC Pharmaceuticals Corporation