Corixa and GlaxoSmithKline Announce Submission of Bexxar Data and Documentation in Support of the Response to U.S. FDA's Complete Review Letter.

Business Editors, Health/Medical Writers

SEATTLE & PHILADELPHIA--(BW HealthWire)--Aug. 9, 2001

Corixa Corporation (Nasdaq:CRXA) and GlaxoSmithKline (NYSE:GSK) today announced the recent submission of documentation, data and analyses to the U.S. Food and Drug Administration (FDA) in support of the response to the FDA's Complete Review Letter received on March 16, 2001 regarding the Biologics License Application (BLA) for Bexxar(TM) (tositumomab, iodine I 131 tositumomab), a novel radioimmunotherapy.

The companies are seeking marketing approval of Bexxar for the treatment of relapsed or refractory, low-grade or transformed low-grade non-Hodgkin's lymphoma.

The submission contains a complete response to all questions raised regarding the Chemistry, Manufacturing and Controls section of the BLA, and to a majority of the questions regarding the clinical section of the BLA. The remainder of the response will be submitted following final compilation of an independent review of clinical response data from two recently completed Bexxar trials, as well as technical database information which was discussed by the agency in the last week. Corixa expects to submit the remainder of the response shortly. Additionally, the companies expect the review period will commence upon FDA acceptance of all data submitted in response to the FDA's Complete Review Letter.

"We look forward to our continuing dialogue with the FDA and to progressing the review of the Bexxar BLA as we continue to seek regulatory approval for this novel radioimmunotherapy," said Steven Gillis, Ph.D., chairman and chief executive officer of Corixa Corporation.

"GlaxoSmithKline is pleased with the progress that has been made to date in responding to the request for information raised in the FDA Complete Review Letter," said Kevin Lokay, vice president of Oncology at GlaxoSmithKline. "We have been working closely with Corixa to ensure the submission meets FDA requirements. GlaxoSmithKline is committed to bringing this innovative therapy to market and to the patients who can benefit from Bexxar."

About Corixa

Corixa is a developer of immunotherapeutics with a commitment to treating and preventing autoimmune diseases, cancer and infectious diseases by understanding and directing the immune system. Corixa is focused on immunotherapeutic products and has a broad technology platform enabling both fully integrated vaccine design and the use of its separate, proprietary product components on a standalone basis. Corixa currently has 16 programs in clinical development and 22 programs in preclinical development, including its most advanced product candidate, Bexxar(TM), a monoclonal antibody conjugated to a radioisotope.

The company partners with numerous developers and marketers of pharmaceuticals, targeting products that are Powered by Corixa(TM) technology with the goal of making its potential products available to patients around the world. Corixa was founded in 1994 and is headquartered in Seattle, Wash., with additional operations in Hamilton, Mont. and South San Francisco, Calif. For more information, please visit Corixa's website at www.corixa.com or call the company's investor relations information line at 1-877/4CORIXA or 1-877/426-7492.

About GlaxoSmithKline

GlaxoSmithKline -- one of the world's leading research-based pharmaceutical and healthcare companies -- is committed to improving the quality of human life by enabling people to do more, feel better and live longer.

GlaxoSmithKline is committed to the research, development, manufacturing and marketing of therapeutic. and supportive care products for hematology and oncology patients. Currently, GlaxoSmithKline Oncology markets Zofran(R) (ondansetron HCl), Hycamtin(R) (topotecan hydrochloride), Navelbine(R) (vinorelbine tartrate) Injection, Argatroban Injection, Alkeran(R) (melphalan), Leukeran(R) (chlorambucil), Compazine(R) (prochlorperazine), Purinethol(R) (mercaptopurine), Myleran(R) (busulfan), and Thioguanine. GlaxoSmithKline Oncology has novel agents in late-stage development, including a radioimmunotherapy Bexxar(TM) (tositumomab, iodine 131 tositumomab). For company information, visit GlaxoSmithKline on the World Wide Web at www.gsk.com.

Corixa Forward-Looking Statement

Except for the historical information presented, certain matters discussed in this press release are forward-looking statements. Forward-looking statements are based on the opinions and estimates of management at the time the statements are made. They are subject to certain risks and uncertainties that could cause actual results to differ materially from any future results, performance or achievements expressed or implied by such statements. Factors that could affect Corixa's actual results include, but are not limited to, failure of the FDA to approve Bexxar(TM) for commercial sale and the "Factors Affecting Our Operating Results, Our Business and Our Stock Price," described in our Quarterly Report on Form 10-Q for the quarter ended March 31, 2001, copies of which are available from our investor relations department. Readers are cautioned not to place undue reliance on these forward-looking statements, which speak only as of the date of this release.

GlaxoSmithKline Forward-Looking Statement

Under the safe harbor provisions of the US Private Securities Litigation Reform Act of 1955, the Company cautions investors that any forward-looking statements or projections made by the Company, including those made in this Announcement, are subject to risks and uncertainties that may cause actual results to differ materially from those projected. Factors that may affect the Group's operations are described under Risk Factors in the Operating and Financial Review and Prospects in the Company's Annual Report on Form 20-F for 2000, filed with the US Securities and Exchange Commission.