Seattle Genetics, Inc. (NASDAQ:SGEN) announced that it has completed patient enrollment in a phase IIb clinical trial of lintuzumab (SGN-33) in combination with low-dose cytarabine chemotherapy for patients with acute myeloid leukemia (AML).

"We are pleased to have achieved our enrollment goal of 210 patients in this global phase IIb trial in less than 18 months," said Thomas C. Reynolds, M.D., Ph.D., Chief Medical Officer of Seattle Genetics. "This trial is designed to determine if combining lintuzumab with a low-dose regimen of chemotherapy extends survival in older AML patients, a setting where there are limited treatment alternatives and patients have a median survival of less than six months. We anticipate that data from the trial, which is event-driven, will be available in the first half of 2010."

The lintuzumab phase IIb clinical trial is a randomized, double-blind, placebo-controlled study evaluating whether the combination regimen of lintuzumab and low-dose cytarabine chemotherapy extends overall survival compared to low-dose cytarabine alone in previously untreated AML patients age 60 and older who decline intensive chemotherapy. The primary endpoint of the study, which is being conducted at more than 80 clinical sites worldwide, is overall survival.

Lintuzumab is a humanized monoclonal antibody that targets the CD33 antigen, which is expressed on a number of hematologic malignancies, including AML and myelodysplastic syndromes (MDS). In addition to the phase IIb clinical trial, Seattle Genetics expects to present data from both the phase I single-agent trial of lintuzumab in AML and MDS and the phase I trial of lintuzumab in combination with Revlimid® (lenalidomide) in advanced MDS during 2009. Lintuzumab has been granted orphan drug designation by the U.S. Food and Drug Administration (FDA) for both AML and MDS.

AML is the most common type of acute leukemia in adults. According to the American Cancer Society, an estimated 13,000 new cases of AML were to be diagnosed in the United States in 2008. Approximately two-thirds of AML patients are over 60 years of age at diagnosis, many of whom are unable to tolerate the toxic side effects of intensive chemotherapy. AML results in uncontrolled growth and accumulation of malignant cells, or "blasts", which fail to function normally and block the production of normal blood cells, leading to a deficiency of red cells (anemia), platelets (thrombocytopenia) and normal white cells (neutropenia) in the blood.

About Seattle Genetics

Seattle Genetics is a clinical stage biotechnology company focused on the development and commercialization of monoclonal antibody-based therapies for the treatment of cancer and autoimmune disease. The company is conducting a pivotal trial of its lead product candidate, SGN-35, under a Special Protocol Assessment with the FDA. SGN-35 is empowered by Seattle Genetics' proprietary antibody-drug conjugate (ADC) technology comprising highly potent synthetic drugs and stable linkers for attaching the drugs to monoclonal antibodies. In addition, Seattle Genetics has three other product candidates in ongoing clinical trials: dacetuzumab (SGN-40), lintuzumab (SGN-33) and SGN-70. Dacetuzumab is being developed under a worldwide collaboration with Genentech. Seattle Genetics also has collaborations for its ADC technology with a number of leading biotechnology and pharmaceutical companies, including Genentech, Bayer, CuraGen, Progenics, Daiichi Sankyo and MedImmune, a subsidiary of AstraZeneca, as well as an ADC co-development agreement with Agensys, a subsidiary of Astellas Pharma. More information can be found at seattlegenetics.

Certain of the statements made in this press release are forward-looking, such as those, among others, relating to the therapeutic potential of lintuzumab and expectations of data availability from the phase I and phase IIb clinical trials. Actual results or developments may differ materially from those projected or implied in these forward-looking statements. Factors that may cause such a difference include the inability to show sufficient safety or activity in clinical trials of lintuzumab and the risk of adverse clinical results as lintuzumab advances in such clinical trials. More information about the risks and uncertainties faced by Seattle Genetics is contained in the company's filings with the Securities and Exchange Commission. Seattle Genetics disclaims any intention or obligation to update or revise any forward-looking statements, whether as a result of new information, future events or otherwise.

Seattle Genetics

View drug information on Revlimid.