New Data Show Improved Outcomes in Certain Lymphomas With ZEVALIN(R) Radioimmunotherapy.

ATLANTA -- Abstracts Presented at ASCO Annual Meeting Explore Use of ZEVALIN in First-Line Therapy, Retreatment and Transplant Combinations

Biogen Idec Inc. (Nasdaq:BIIB) and Schering AG, Germany (FSE:SCH) (NYSE:SHR) announced new data presented this week at the 42nd American Society of Clinical Oncology (ASCO) Annual Meeting in Atlanta, Ga., showing that lymphoma patients with refractory and hard-to-treat disease -- specifically mantle cell lymphoma (MCL), follicular non-Hodgkin's lymphoma (NHL) and primary central nervous system (CNS) lymphoma -- experienced improved response and remission rates following administration of ZEVALIN(R) (Ibritumomab Tiuxetan) radioimmunotherapy as consolidation treatment after other, more standard therapies have been given. Additionally, data suggest the use of ZEVALIN as a component of a transplant regimen may reduce patients' risk of relapse.

"We are pleased that the data at this year's ASCO meeting continues to explore ZEVALIN's ability to impact a broad range of patients, and underscores the growing role that ZEVALIN can play in the standard of care for lymphoma," said Dr. Wayne Saville, director of Medical Affairs for Biogen Idec.

Eleven abstracts were presented on ZEVALIN data. Highlights include the following:

Use of ZEVALIN in MCL and FL Patients

    --  First-line consolidation with ZEVALIN in difficult-to-treat
        MCL -- Mitchell R. Smith, M.D., Ph.D., lead study investigator
        and director of Lymphoma Service, Fox Chase Cancer Center,
        presented data from the Eastern Cooperative Oncology Group
        Study E1499 on the use of ZEVALIN following administration of
        R-CHOP in previously untreated patients with stage II-IV MCL.
        The study was designed to evaluate response and toxicity, with
        a primary endpoint of time-to-treatment failure.

        After four cycles of R-CHOP, seven of the 50 evaluable
        patients in the study (14 percent) achieved a complete
        response (CR/CRu) and 29 (58 percent) achieved a partial
        response. Following treatment with ZEVALIN, responses improved
        in 15 of 37 patients. Twelve of the patients with a partial
        response exhibited a complete response after ZEVALIN, two
        patients with stable disease exhibited a partial response, and
        one patient moved from stable disease to a complete response.
        The final response rate following ZEVALIN administration was
        84 percent, with a complete response rate of 45 percent, more
        than triple the rate following R-CHOP alone.

    --  ZEVALIN as part of consolidation therapy in MCL -- Oliver
        Weigert, M.D., University Hospital Grosshadern/LMU, Munich,
        Germany, presented data from two Phase 2 trials of patients
        with relapsed or refractory MCL. Twenty-two patients were
        evaluated to identify predictors or response. Seven of 14
        patients with residual tumor burden after cytoreduction
        converted from partial to complete remission following
        administration of ZEVALIN, and 14 of the 16 evaluable patients
        receiving consolidation ZEVALIN therapy were in remission.
        Bulky disease before ZEVALIN therapy was the most prominent
        adverse risk factor with no response in these patients.
        Patients with fewer prior therapies (less than 2) had
        significantly higher response rates.

    --  Predictive value of 111In and PET-CT scans during ZEVALIN
        consolidation in Follicular Lymphoma (FL) -- Nicholas A.
        DeMonaco, M.D., University of Pittsburgh, presented data from
        an ongoing Phase 2 trial for the predictive value of 111In
        scans and PET/CT results. The proportion of patients with a
        negative PET scan was eight of 15 (53.3 percent) after CHOP-R
        compared with 100 percent after ZEVALIN was added. Using IWG
        criteria in combination with PET scan results, the complete
        response rate increased from 26.7 percent after CHOP-R to 80
        percent after ZEVALIN. There was no difference in the complete
        response rate in patients tumor uptake by 111In scan and those
        with a negative 111In scan. Data from this trial suggest that
        functional imaging with PET-CT may be a more sensitive method
        than CT alone in determining residual disease in follicular
        lymphoma (FL).

    ZEVALIN with ASCT or PBSC

    --  Evaluation of dose escalation with ZEVALIN in ASCT -- Ian W.
        Flinn, M.D., Johns Hopkins Oncology Center, presented
        preliminary data of patients with relapsed or refractory
        low-grade mantle cell or diffuse B-Cell NHL when ZEVALIN was
        administered with autologous stem cell transplantation (ASCT).

    --  Evaluation of ZEVALIN in NHL -- Avichai Shimoni, M.D., Chaim
        Sheba Medical Center, Tel Aviv, Israel, presented preliminary
        data regarding administration of ZEVALIN and high-dose
        chemotherapy prior to ASCT in chemo-refractory aggressive NHL.

    --  High dose ZEVALIN in heavily pre-treated NHL patients -- Anna
        Vanazzi, M.D., European Institute of Oncology, Milan, Italy,
        presented preliminary data from a Phase 1/2 trial evaluating
        ZEVALIN with peripheral blood stem cell support (PBSC).

    Additional ZEVALIN Abstracts

    --  Retreatment with ZEVALIN in patients with follicular NHL --
        Andres Forero, M.D., Comprehensive Cancer Center, UAB Health
        System, presented the first safety and efficacy data related
        to treating follicular NHL with a second course of ZEVALIN.

    --  ZEVALIN in combination with gemcitabine -- Hossein Borghaei,
        D.O., Fox Chase Cancer Center, presented preliminary data from
        a Phase 1 trial designed to assess the safety of concomitant
        administration of ZEVALIN with gemcitabine in patients with
        NHL.

    --  ZEVALIN in PCNSL -- Philipp Kiewe, M.D., Charite Campus
        Benjamin Franklin, Berlin, Germany, offered preliminary data
        on treatment with ZEVALIN in previously-treated patients with
        primary CNS lymphoma (PCNSL).

ZEVALIN Safety Profile

Rare deaths have occurred within 24 hours of rituximab (RITUXAN) infusions. These fatalities were associated with an infusion reaction symptom complex that included hypoxia, pulmonary infiltrates, acute respiratory distress syndrome, myocardial infarction, ventricular fibrillation or cardiogenic shock. Yttrium-90 ZEVALIN administration results in severe and prolonged cytopenias in most patients. Patients experiencing severe cutaneous and mucocutaneous reactions should not receive any further components of the ZEVALIN therapeutic regimen and should seek prompt medical evaluation.

In safety data based upon 349 patients, the most serious adverse reactions of the ZEVALIN therapeutic regimen were primarily hematologic, with grade 3/4 neutropenia, thrombocytopenia, and anemia occurring in 60 percent, 63 percent and 17 percent respectively. Infusion-related toxicities were typically grade 1 or 2 and were associated with pre-administration of rituximab. The risk of hematologic toxicity correlated with the degree of bone marrow involvement prior to ZEVALIN therapy. Myelodysplasia or acute myelogenous leukemia was observed in 2 percent of patients (8 to 34 months after treatment).

ZEVALIN should only be used by health care professionals qualified by training and experience in the safe use of radionuclides.

About ZEVALIN

On February 19, 2002, the ZEVALIN (Ibritumomab Tiuxetan) therapeutic regimen was approved by the U.S. Food and Drug Administration (FDA) for the treatment of patients with relapsed or refractory low grade, follicular or transformed B-cell non Hodgkin's lymphoma (NHL), including patients with rituximab (RITUXAN) refractory follicular non-Hodgkin's lymphoma. Determination of the effectiveness of ZEVALIN in a relapsed or refractory patient population is based on overall response rates. The effects of ZEVALIN on survival are not known. Radioimmunotherapy offers an option to patients with certain types of B-cell non-Hodgkin's lymphoma who have failed to adequately respond to other cancer therapies.

The ZEVALIN therapeutic regimen combines a monoclonal antibody with a radioisotope. The monoclonal antibody in ZEVALIN recognizes and attaches to a particular cell-surface protein on B-cells called the CD20 antigen. This allows ZEVALIN to specifically target B-cells, destroying malignant NHL B-cells and also normal B-cells.

About Biogen Idec

Biogen Idec creates new standards of care in oncology, neurology and immunology. As a global leader in the development, manufacturing, and commercialization of novel therapies, Biogen Idec transforms scientific discoveries into advances in human healthcare. For ZEVALIN product labeling, press releases and additional information about the company, please visit http://www.biogenidec.com.

Biogen Idec Safe Harbor

This press release contains forward-looking statements regarding ZEVALIN as a treatment for various indications. These statements are based on the companies' current beliefs and expectation. Drug development involves a high degree of risk. Factors which could cause actual results to differ materially from the companies' current expectations include: the risk that unexpected concerns may arise from additional data or analysis, that regulatory authorities may require additional information, further studies, or may fail to approve the drug, or that the company may encounter other unexpected hurdles. For more detailed information on the risks and uncertainties associated with Biogen Idec's drug development and other activities, see the periodic reports of Biogen Idec Inc. filed with the Securities and Exchange Commission. Biogen Idec assumes no obligation to update any forward-looking statements, whether as a result of new information, future events or otherwise.

About Schering AG

Schering AG is a research-based pharmaceutical company. Its activities are focused on four business areas: Gynecology&Andrology, Oncology, Diagnostic Imaging as well as Specialized Therapeutics for disabling diseases. As a global player with innovative products Schering AG aims for leading positions in specialized markets worldwide. With in-house R&D and supported by an excellent global network of external partners, Schering AG is securing a promising product pipeline. Using new ideas, Schering AG aims to make a recognized contribution to medical progress and strives to improve the quality of life: making medicine work.