$168 Million In US Rituxan Sales Announced By IDEC Pharmaceuticals for the First Quarter, 2001

Following Genentech's first quarter earnings release, Idec Pharmaceuticals Corporation announced that the collaboration between Idec and Genentech, Inc. achieved US net sales of Rituxan totaling $168.0 million for the three months ended March 31, 2001. Based on this level of sales Idec estimates net income of approximately $0.12 per share on a diluted basis for the first quarter of 2001.

Idec's full financial results for the first quarter are expected to be released on April 19, 2001, after the close of market. Following the release, between 1:30-2:30 p.m. Pacific Standard Time on April 19, 2001, Idec will conduct a live webcast of IDEC management's discussion of the first quarter financial results and a regulatory update on Zevalim.

US sales performance for Rituxan in the first quarter continues to build on the strong growth we began to see this time last year," said William R. Rohn, Idec's chief operating officer in a press statement. "US net sales for the quarter are up 115 percent compared to the same quarter last year."

The net sales of Rituxan reported by Genentech in the first quarter included $4.1 million of ex-US sales to its partner F Hoffmann-La Roche Ltd. Idec's royalty revenue on sales of Rituximab outside the US is based on Roche's end-user sales and is booked with a one-quarter lag. Idec will recognize, during the first quarter of 2001, $2.6 million in royalties from Roche's end-user sales reported during the fourth quarter of last year.

Rituxan was discovered by Idec and is copromoted in the US by Idec and Genentech. Rituxan is jointly developed by Idec, Genentech Inc., F. Hoffmann-La Roche Ltd. of Switzerland and Zenyaku Kogyo Co. Ltd. of Japan. Roche has marketing rights to Rituximab outside of the US and Japan.