Seattle Genetics, Inc. (Nasdaq: SGEN) today announced the initiation of two phase I clinical trials of SGN-CD19A, one for patients with B-cell acute lymphoblastic leukemia (ALL) and one for patients with B-cell non-Hodgkin lymphomas. SGN-CD19A utilizes Seattle Genetics’ industry-leading antibody-drug conjugate (ADC) technology. The trials are designed to assess the safety and antitumor activity of SGN-CD19A, an ADC targeted to CD19. “CD19 is expressed in a variety of hematologic malignancies, including non-Hodgkin lymphoma and ALL, and has limited expression on normal tissues making it an ideal ADC target. Our preclinical data indicate that SGN-CD19A internalizes rapidly into tumor cells, resulting in targeted cell killing,” said Jonathan Drachman, M.D., Senior Vice President, Research and Translational Medicine at Seattle Genetics. “Our SGN-CD19A clinical development program comprises two trials that, together, will provide a robust understanding of the activity and tolerability of this ADC in patients with aggressive CD19-positive lymphomas or ALL. In addition to the five ADCs already in ongoing clinical trials, we plan to advance two additional ADC programs into the clinic during 2013, underscoring our leadership in the field.” The studies are phase I, open-label, dose-escalation clinical trials. The primary endpoints are to estimate the maximum tolerated dose and to evaluate the safety of SGN-CD19A. In addition, the trials will evaluate antitumor activity, pharmacokinetics, progression-free survival and overall survival. One trial will enroll adult and pediatric patients with relapsed or refractory B-cell ALL, as well as patients with Burkitt lymphoma or leukemia or B-cell lymphoblastic lymphoma . The dose escalation portion of the study is designed to evaluate both weekly and every three week schedules and will enroll approximately 80 patients at multiple centers in the United States. A second trial will enroll patients with relapsed or refractory aggressive B-cell non-Hodgkin lymphomas, including diffuse large B-cell lymphoma (DLBCL) and mantle cell lymphoma. The dose escalation portion of the trial will evaluate SGN-CD19A administered every three weeks and will enroll approximately 25 patients at multiple centers in the United States. Both trials permit additional patients to be enrolled into expansion cohorts following determination of the maximum tolerated dose.
For more information about the trials, including enrolling centers, please visit www.clinicaltrials.gov.About SGN-CD19A SGN-CD19A is an ADC composed of an anti-CD19 antibody attached to a synthetic cytotoxic cell-killing agent, monomethyl auristatin F (MMAF), using Seattle Genetics’ proprietary technology. The ADC is designed to be stable in the bloodstream, and to release its cytotoxic agent upon internalization into CD19-expressing cells. This approach is intended to spare non-targeted cells and thus reduce many of the toxic effects of traditional chemotherapy while enhancing the antitumor activity. About Acute Lymphoblastic Leukemia Acute lymphoblastic leukemia, also called acute lymphocytic leukemia or ALL, is an aggressive type of cancer of the bone marrow and blood that progresses rapidly without treatment. In ALL, lymphoblasts, which are malignant, immature white blood cells, multiply and crowd out normal cells in the bone marrow. ALL is the most common type of cancer in children. According to the American Cancer Society, approximately 6,000 people were to be diagnosed with ALL during 2012 and more than 1,400 would die from the disease. About Non-Hodgkin Lymphoma Lymphoma is a general term for a group of cancers that originate in the lymphatic system. There are two major categories of lymphoma: Hodgkin lymphoma and non-Hodgkin lymphoma. Non-Hodgkin lymphoma is further categorized into indolent (low-grade) or aggressive, including DLBCL. DLBCL is the most common type of non-Hodgkin lymphoma. According to the American Cancer Society, more than 70,000 cases of non-Hodgkin lymphoma were to be diagnosed in the United States during 2012 and nearly 19,000 people would die from the disease. About Seattle Genetics Seattle Genetics is a biotechnology company focused on the development and commercialization of monoclonal antibody-based therapies for the treatment of cancer. The company’s lead program, ADCETRIS, received accelerated approval from the U.S. Food and Drug Administration in August 2011 and approval with conditions from Health Canada in February 2013 for two indications. In addition, under a collaboration with Millennium: The Takeda Oncology Company, ADCETRIS received conditional approval from the European Commission in October 2012. Seattle Genetics also has four other clinical-stage antibody-drug conjugate (ADC) programs: SGN-75, ASG-5ME, ASG-22ME and SGN-CD19A. Seattle Genetics has collaborations for its ADC technology with a number of leading biotechnology and pharmaceutical companies, including Abbott, Agensys (an affiliate of Astellas), Bayer, Celldex Therapeutics, Daiichi Sankyo, Genentech, GlaxoSmithKline, Millennium, Pfizer and Progenics, as well as ADC co-development agreements with Agensys and Genmab. More information can be found at www.seattlegenetics.com. Certain of the statements made in this press release are forward-looking, such as those, among others, relating to the therapeutic potential of SGN-CD19A. 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 activity in these recently initiated clinical trials and the risk of adverse events as SGN-CD19A advances in clinical trials. More information about the risks and uncertainties faced by Seattle Genetics is contained in the company’s 10-Q for the quarter ended September 30, 2012 filed 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.