Filed by Tularik Inc.

Pursuant to Rule 425

Under the Securities Act of 1933, as amended

And Deemed Filed Pursuant to Rule 14a-12

Under the Securities Exchange Act of 1934, as amended

Subject Company: Tularik Inc.

Commission File No.: 000-28397

Contacts: Tularik Inc.

Traci McCarty

650-825-7182

Alicia Williams

650-825-7322

TULARIK POSTPONES ANNUAL STOCKHOLDERS’ MEETING

South San Francisco, Calif. April 8, 2004 – Tularik Inc. (NASDAQ: TLRK) today announced that its previously noticed annual meeting of stockholders has been postponed indefinitely. Tularik postponed the annual meeting, originally scheduled for Tuesday, April 20, 2004, in light of the recently announced proposed merger of Tularik with a wholly-owned subsidiary of Amgen in a stock-for-stock transaction. In place of its annual meeting, Tularik intends to hold a special meeting of stockholders for the purpose of considering and voting upon a proposal to approve the merger agreement and merger. The date of the special meeting will be determined subsequent to the parties’ requisite filings with the Securities and Exchange Commission (SEC) and completion of any SEC review. Tularik’s annual meeting of stockholders will only be held in the event the merger is not approved or otherwise does not occur, in which case a new date for the annual meeting will be announced.

About Tularik

Tularik is engaged in the discovery and development of a broad range of novel and superior orally available medicines that act through the regulation of gene expression. Tularik’s scientific platform is focused on three therapeutic areas: cancer, inflammation and metabolic disease. Tularik currently has five drug candidates in clinical trials. In the cancer area, Tularik is currently conducting a pivotal study of T67 for the treatment of hepatocellular carcinoma and Phase 2 trials with T607 for the treatment of gastric and esophageal cancer. T487, for the treatment of inflammatory diseases, and T131, for the treatment of type 2 diabetes, are in Phase 2 trials to evaluate safety and pharmacokinetic parameters. T71 for the treatment of obesity has recently commenced Phase 1 trials.

Additional Information about the Merger and Where to Find It

In connection with Amgen’s proposed acquisition of Tularik (“Acquisition”), Tularik intends to file a proxy statement and other relevant materials and Amgen intends to file a registration statement/prospectus and other relevant materials, with the Securities and Exchange Commission

(SEC). INVESTORS AND SECURITY HOLDERS OF AMGEN AND TULARIK ARE URGED TO READ THE PROXY STATEMENT/PROSPECTUS AND THE OTHER RELEVANT MATERIALS WHEN THEY BECOME AVAILABLE BECAUSE THEY WILL CONTAIN IMPORTANT INFORMATION ABOUT AMGEN, TULARIK AND THE ACQUISITION. The proxy statement/prospectus and other relevant materials (when they become available), and any other documents filed by Amgen or Tularik with the SEC, may be obtained free of charge at the SEC’s web site at www.sec.gov. In addition, investors and security holders may obtain free copies of the documents filed with the SEC by Amgen by directing a written request to: Amgen Inc., One Amgen Center Drive, Thousand Oaks, CA 91320-1799, Attn: Investor Relations. Investors and security holders may obtain free copies of the documents filed with the SEC by Tularik by contacting Tularik Inc., Attn: Investor Relations at 1120 Veterans Blvd., South San Francisco, CA 94080. Investors and security holders are urged to read the proxy statement, prospectus and the other relevant materials when they become available before making any voting or investment decision with respect to the Acquisition.

Amgen, Tularik and their respective executive officers and directors may be deemed to be participants in the solicitation of proxies from the stockholders of Tularik in favor of the Acquisition. Information about those executive officers and directors of Amgen and their ownership of Amgen common stock is set forth in the Amgen Form 10-K for the year ended December 31, 2003, which was filed with the SEC on March 11, 2004. Information about the executive officers and directors of Tularik and their ownership of Tularik common stock is set forth in the proxy statement for Tularik’s 2004 Annual Meeting of Stockholders, which was filed with the SEC on March 17, 2004. Investors and security holders may obtain more detailed information regarding the direct and indirect interests of Amgen, Tularik and their respective executive officers and directors in the Acquisition by reading the proxy statement/prospectus regarding the Acquisition when it becomes available.

Forward-Looking Statements

This press release contains forward-looking statements within the meaning of the “safe harbor” provisions of the Private Securities Litigation Reform Act of 1995, including statements about future financial and operating results and Amgen’s anticipated acquisition of Tularik. These statements are based on management’s current expectations and beliefs and are subject to a number of risks, uncertainties and assumptions that could cause actual results to differ materially from those described in the forward-looking statements.

Tularik is providing this information as of the date of this news release and Tularik does not undertake any obligation to update any forward-looking statements contained in this document as a result of new information, future events or otherwise.