CAMPATH Gains Visiblity at Key Oncology Meeting.

Business Editors

SAN ANTONIO--(BUSINESS WIRE)--Dec. 8, 2003

More Than 65 Abstracts Featured at ASH

ILEX(TM) Oncology, Inc. (NASDAQ:ILXO) reported today that several important CAMPATH(R) (alemtuzumab) studies are being presented at the American Society of Hematology 45th Annual Meeting and Exposition. CAMPATH is approved for the treatment of patients with B-cell chronic lymphocytic leukemia (B-CLL) who have been treated with alkylating agents and have failed fludarabine treatment. New data focuses on the significance of minimal residual disease as a predictor for prolonged survival, as well as managing CAMPATH's side effect profile.

Highlights of the CAMPATH investigator-sponsored studies follow.

-- Researchers reported that the absence of minimal residual

disease is the best predictor for prolonged survival of

patients with chronic lymphocytic leukemia (CLL). The overall

survival for patients that achieved an MRD negative remission

was 84% at 5 years following treatment with CAMPATH.

-- Data show CAMPATH cleared residual bone marrow disease in most

patients following chemotherapy and a molecular remission was

achieved in 11 of 29 patients (38%) in whom polymerase chain

reaction (PCR) results were available. The overall response

rate was 53 percent. Additionally, patients treated at a

higher dose of Campath had a higher response rate than those

treated at a lower dose (65 percent versus 39 percent,

respectively).

-- Preliminary data from a Phase III study to evaluate the

efficacy and safety of front-line therapy with CAMPATH vs

chlorambucil in patients with progressive B-cell chronic

lymphocytic leukemia (B-CLL) showed that therapy-naive

patients have comparable safety profiles and an independent

Data and Safety Monitoring Board have recommended that the

study continue.

-- Two separate studies report that pre-emptive screening for

cytomegalovirus (CMV) reactivation during CAMPATH treatment

and early detection results in the safe and effective

management of the virus.

About CAMPATH

CAMPATH is a humanized monoclonal antibody that binds to a specific target, CD52, on cell surfaces, leading the body's immune system to destroy malignant cells and deplete B- and T-cells that are instrumental in disease. CAMPATH was granted accelerated approval by the U.S. Food and Drug Administration in May 2001.

Schering AG, Germany (FSE:SCH) (NYSE:SHR) holds exclusive worldwide marketing and distribution rights to CAMPATH. The product is marketed in the U.S. by Berlex Laboratories Inc., a U.S. affiliate of the Schering AG Group. CAMPATH was launched in the U.S. in June 2001, and in Europe, where it is named MABCAMPATH, in August 2001.

About ILEX

Founded in 1994 as an oncology drug development company, ILEX is strategically positioned to become a product-driven biopharmaceutical company, focused primarily in oncology. ILEX has a marketed product, CAMPATH(R) in the United States and MABCAMPATH(R) in the European Union, and is advancing an innovative and diversified pipeline of compounds focused on the treatment of cancer. The ILEX pipeline comprises product candidates at various stages of clinical development, including cytotoxic and cytostatic agents with novel mechanisms of action, monoclonal antibodies, angiogenesis inhibitors and signal transduction inhibitors. ILEX maintains a core competency in oncology drug development, with locations in San Antonio, Texas, and Guildford, England. ILEX also conducts research in angiogenesis inhibition, cell signaling, medicinal chemistry and nuclear receptor biology at its laboratories in Boston, Mass., and Geneva, Switzerland. Further information about ILEX can be found on the company's web site at www.ilexonc.com.

Certain statements contained herein are "forward-looking" statements (as such term is defined in the Private Securities Litigation Reform Act of 1995). Because these statements include risks and uncertainties, actual results may differ materially from those expressed or implied by such forward-looking statements. Specifically, factors that could cause actual results to differ materially from those expressed or implied by such forward-looking statements include, but are not limited to: risks associated with preclinical and clinical developments in the biopharmaceutical industry in general and in ILEX's compounds under development in particular; market acceptance of CAMPATH(R); the ability to expand the number and scope of the indications for which CAMPATH(R) is approved; the potential failure of ILEX's compounds under development to prove safe and effective for treatment of disease; uncertainties inherent in the early stage of ILEX's compounds under development; failure to successfully implement or complete clinical trials; failure to receive marketing clearance from regulatory agencies for our compounds under development; acquisitions, divestitures, mergers, licenses or strategic initiatives that change ILEX's business, structure or projections; the ability of ILEX to predict its future expenses and capital needs; the development of competing products; uncertainties related to ILEX's dependence on third parties and partners; and those risks described in ILEX's report on Form 8-K filed on November 13, 2003, and in other filings made by ILEX with the SEC. ILEX disclaims any obligation to update these forward-looking statements.