Biogen Idec (NASDAQ: BIIB) announced today that data presented at the 43rd American Society of Clinical Oncology (ASCO) annual meeting showed that adding Zevalin® (Ibritumomab tiuxetan) radioimmunotherapy to a short course first-line treatment followed by rituximab weekly for four weeks doubled the rate of complete response in patients with follicular lymphoma, from 44 percent with a standard treatment regimen to 88 percent. Additionally, the response rate (complete and partial responses) for patients in the study was 100 percent based on PET scan assessment.
“The increase in complete response rates when adding ZEVALIN radioimmunotherapy is promising,” said Samuel A. Jacobs, M.D., associate director for clinical investigations at the University of Pittsburgh Cancer Institute and UPMC Cancer Centers. “These data add to the growing body of evidence that using radioimmunotherapy as part of front-line treatment may increase complete response rates.”
About The Trial
In this Phase II study, patients with symptomatic, stages II-IV and grades 1-3, untreated follicular lymphoma received three cycles of R-CHOP, a standard treatment regimen, followed by ZEVALIN. One week after ZEVALIN treatment, patients received rituximab weekly for four weeks. The primary endpoint of the trial was complete response rate, which was determined by CT scan, the conventional methodology, and PET scan. Of 56 evaluable patients, 50 completed both phases of therapy and were evaluated for response.
Results evaluated by CT scan showed that 44 percent of patients had a complete response following the R-CHOP phase of treatment. After treatment with ZEVALIN and extended dose rituximab, complete response rate increased to 88 percent. Results evaluated by PET scan, a newer method of evaluation, showed a complete response rate of 68 percent with R-CHOP and 96 percent after treatment with ZEVALIN and extended dose rituximab. The response rate in patients who completed the treatment regimen was 100 percent based on PET scan assessment. Median time to progression has not yet been reached; to date, five patients have experienced disease progression. Adverse events included myelosuppression and there was one episode of febrile neutropenia after ZEVALIN and rituximab treatment.
“We believe that ZEVALIN may play an important role in the treatment of lymphoma in the front-line setting and are encouraged that data continues to underscore the impact that radioimmunotherapy can have,” said David Parkinson, M.D., senior vice president, Oncology Research and Development, Biogen Idec. “In order to further understand the potential of ZEVALIN as a first-line treatment, we have recently initiated a phase III trial that will evaluate ZEVALIN as part of first-line treatment with CVP, a commonly-used chemotherapy regimen.”
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. Myelodysplastic syndrome (MDS) and/or acute myelogenous leukemia (AML) were reported in 5.2% (11/211) of patients enrolled in clinical studies and 1.5% (8/535) of patients included in the expanded-access trial, with median follow-up of 6.5 and 4.4 years, respectively. ZEVALIN should only be used by health care professionals qualified by training and experience in the safe use of radionuclides.
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 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.