1 EXHIBIT 23.1 [KPMG PEAT MARWICK LLP LETTERHEAD] INDEPENDENT AUDITORS' CONSENT The Board of Directors IDEC Pharmaceuticals Corporation: We consent to the use of our report incorporated herein by reference in the registration statement on Form S-8 of IDEC Pharmaceuticals Corporation. /s/ KPMG Peat Marwick LLP San Diego, California June 19, 1997