Release Details

CARLSBAD, Calif., April 29 /PRNewswire-FirstCall/ -- Isis Pharmaceuticals, Inc., (Nasdaq: ISIS) announces the following webcast:

     What:     Isis Pharmaceuticals 2004 First Quarter Financial Results



     When:     Thursday, May 6 at 10:00 AM (EDT)



     Where:    http://www.firstcallevents.com/service/ajwz405840956gf12.html
               or www.isispharm.com



     How:      Live on the internet. Simply log onto either of the web sites
               listed above.



     Contact:  Kristina Peterson
               Corporate Communications
               (760) 603-2521

If you are unable to participate during the live event a replay of the webcast will be available at www.isispharm.com for up to 30 days.

Isis Pharmaceuticals, Inc. is exploiting its expertise in RNA to discover and develop novel human therapeutic drugs for its pipeline and for its partners. The company has successfully commercialized the world's first antisense drug and has 11 antisense products in development to treat metabolic, cardiovascular, inflammatory and viral diseases and cancer. Through its Ibis Therapeutics® program, Isis is developing a biosensor to identify infectious organisms, and discovering small molecule drugs that bind to RNA. As an innovator in RNA-based drug discovery and development, Isis is the owner or exclusive licensee of more than 1,300 issued patents worldwide. Additional information about Isis is available at www.isispharm.com

This press release contains forward-looking statements concerning Isis Pharmaceuticals, Inc., its clinical development pipeline and the potential value of the company's drug discovery technology platform. Any statement describing a goal, expectation, intention or belief of the company is a forward-looking statement and should be considered an at-risk statement. Such statements are subject to certain risks and uncertainties, particularly those inherent in the process of discovering, developing and commercializing drugs that are safe and effective for use as human therapeutics and financing such activities. Actual results could differ materially from those projected in this release. As a result, you are cautioned not to rely on these forward- looking statements. Factors that could cause or contribute to such differences include, but are not limited to, those discussed in Isis' Annual Report on form 10-K for the year ended December 31, 2003, which is on file with the U.S. Securities and Exchange Commission, copies of which are available from the company.

Ibis Therapeutics® is a registered trademark of Isis Pharmaceuticals, Inc.

SOURCE Isis Pharmaceuticals, Inc.