(BW HealthWire) —
Three Additional Studies of ZEVALIN Also Presented
IDEC Pharmaceuticals Corporation (Nasdaq:IDPH) announced the final results of two pivotal trials of ZEVALIN(TM) (Ibritumomab Tiuxetan), an investigational radioimmunotherapy, during oral presentations at the 42nd Annual Meeting of the American Society of Hematology (ASH).
Thomas E. Witzig, M.D. of the Mayo Clinic, Rochester, MN, today delivered an oral presentation of a Phase III randomized, controlled study of 143 patients with relapsed or refractory low grade, follicular, or CD20-positive transformed B-cell non-Hodgkins lymphoma (NHL). He noted that the ZEVALIN combined with Rituxan arm of the study showed an overall response rate (ORR) of 80 percent, compared to the Rituxan(R) (Rituxumab) alone control arm, which showed an overall response rate of 56 percent. A treatment course for ZEVALIN includes a Rituxan infusion (250 mg/m.2) on day one, followed by infusions of Rituxan (250 mg/m2) and ZEVALIN (at a standard radiation dose of 0.4 mCi/kg of patient body weight) on day eight. A treatment course of the Rituxan control consisted of four weekly doses of 375 mg/m2 of Rituxan.
Dr. Witzig said that 30 percent of the ZEVALIN patients achieved complete responses to therapy. Sixteen percent of Rituxan patients achieved complete responses. To date duration of response estimates between ZEVALIN plus Rituxan and Rituxan alone are not statistically different but further analysis will be conducted as the data mature.
ZEVALIN associated toxicity was primarily hematologic, transient and reversible. Thirty-two percent of patients in the ZEVALIN arm of the study experienced Grade 4 neutropenia (neutrophil count below 500/mm3) and five percent experienced Grade 4 thrombocytopenia (platelet count below 10,000/mm3). Patients who had Grade 3 or greater neutropenia or thrombocytopenia recovered in a median of 14 and 13 days, respectively. Only five patients in the ZEVALIN arm required hospitalization due to infection. The most common adverse events associated with Rituxan were infusion related, consisting mainly of mild to moderate flu-like symptoms, for example fever, chills and rigors that occur in the majority of patients during the first infusion.
Second Pivotal Trial — ZEVALIN in Rituxan-Refractory Follicular NHL Patients
On the previous day Dr. Witzig delivered an oral presentation of the final results of an open-label Phase III pivotal trial of ZEVALIN in 54 follicular NHL patients who are refractory to Rituxan (i.e., non-responders or patients with time-to-progression of less than six months after Rituxan treatment.) He said the ZEVALIN study showed an overall response rate (ORR) of 74 percent.
Dr. Witzig noted that 15 percent of patients achieved complete responses to therapy. ZEVALIN associated toxicity was primarily hematologic, transient and reversible. Thirty-five percent of patients in the study experienced Grade 4 neutropenia (neutrophil count below 500/mm3) and nine percent experienced Grade 4 thrombocytopenia (platelet count below 10,000/mm3). Patients who experienced Grade 3 or greater neutropenia or thrombocytopenia recovered in a median of 8 and 13 days, respectively.
ZEVALIN for Relapsed or Refractory NHL Patients with Mild Thrombocytopenia
On Dec. 4 Dr. Witzig also gave a poster presentation of the final results of a Phase II trial evaluating the safety and efficacy of treating relapsed or refractory, low grade, follicular or transformed NHL patients with mild thrombocytopenia (platelet count between 100,000 and 149,000/mm3) with ZEVALIN at a reduced radiation dose (0.3 mCi/kg). The overall response rate in 30 patients was 67 percent with 10 patients (33 percent) achieving complete responses. Responses were seen even in patients with adverse prognostic factors, such as large tumors or chemoresistant disease.
In the study, 33 percent of patients experienced Grade 4 neutropenia and 13 percent of patients experienced Grade 4 thrombocytopenia. Again, the toxicity of ZEVALIN was primarily hematologic, transient and reversible with patients recovering in a median of 14 days.
ZEVALIN Is Safe and Well-Tolerated in Relapsed or Refractory NHL Patients
In a second poster presentation on Dec. 4, Dr. Witzig summarized the safety results of four clinical trials which showed that ZEVALIN is very well tolerated, even in a refractory population at risk for toxicity. Two hundred and eleven patients with relapsed or refractory, low grade, follicular, transformed or intermediate NHL were treated with ZEVALIN in the following trials: 1) a Phase I/II dose-finding trial, 2) a Phase II trial of reduced doze ZEVALIN (0.3 mCi/kg) in patients with mild thrombocytopenia, 3) a Phase III randomized trial of 0.4 mCi/kg, and 4) a Phase III non-randomized trial of 0.4 mCi/kg in patients with Rituxan-refractory follicular NHL.
Dr. Witzig noted that toxicity in all four trials was primarily hematologic, transient and reversible. Overall, thirty-two percent of patients in the four studies experienced Grade 4 neutropenia and 8.5 percent of patients experienced Grade 4 thrombocytopenia. Only 17 percent of patients used one or more hematopoietic growth factors. There were no excessive infection risks, with only 7.6 percent of patients hospitalized with infections.
Studies of ZEVALIN Show Improved Quality of Life in NHL Patients
On Dec. 4 Gregory A. Wiseman, M.D. of the Mayo Clinic, Rochester, MN, gave a poster presentation that showed that ZEVALIN treatment results in a statistically significant improvement in the NHL patient’s self-assessment of quality of life.
ZEVALIN is a monoclonal antibody that targets the CD20 antigen and is stably linked to the radioisotope yttrium-90. This investigational agent is in late stages of development for the treatment of certain NHLs. On Nov. 1, 2000, IDEC submitted a Biologics License Application (BLA) to the U.S. Food and Drug Administration (FDA) seeking marketing approval of ZEVALIN.
Schering AG has marketing rights to ZEVALIN outside the U.S.
Rituxan is copromoted in the United States by IDEC and Genentech Inc. Rituxan was discovered by IDEC and is jointly developed by IDEC, Genentech, F. Hoffmann-LaRoche Ltd. of Switzerland and Zenyaku Kogyo Company Ltd. of Japan. Roche has marketing rights outside the U.S. and Japan.
IDEC Pharmaceuticals focuses on the commercialization and development of targeted therapies for the treatment of cancer and autoimmune diseases. IDEC’s antibody products act chiefly through immune system mechanisms, exerting their effect by binding to specific, readily targeted immune cells in the patient’s blood or lymphatic systems. For a menu of IDEC’s current news releases and quarterly reports or to retrieve a specific release, call (888) 329-2309. On the Internet check the News Center at IDEC’s website: http://idecpharm.cdmail.biz.
The statements made in this press release contain certain forward-looking statements that involve a number of risks and uncertainties. Actual events or results may differ from IDEC’s expectations. For example, the timing, success and cost of preclinical research and clinical studies, the timing, acceptability and review periods for regulatory filings, the timing of and ability to obtain regulatory approval of products, such as ZEVALIN, the achievement of future product sales, the level of manufacturing performance and the risk factors listed from time to time in IDEC’s SEC filings including but not limited to its S-3 filed on November 16, 2000, its Annual Report on Form 10-K for the year ended December 31, 1999 and Form 10-Q for the quarter ended September 30, 2000, may affect the actual results achieved by IDEC. These forward-looking statements represent the company’s judgment as of the date of this release. The company disclaims, however, any intent or obligation to update these forward-looking statements.
IDEC Pharmaceuticals and Rituxan are registered U.S. trademarks of the company. ZEVALIN is a trademark of the company. The company’s headquarters is located at 3030 Callan Road, San Diego, CA 92121.
IDEC Pharmaceuticals’ press releases are available at no charge through Business Wire’s News on Demand Plus. For a menu of IDEC’s current press releases and quarterly reports or to retrieve a specific release, call 888/329-2309. On the Internet, check the News Center at IDEC’s website http//idecpharm.cdmail.biz.