Stem Cell Research

Seattle Genetics Reports Positive Phase I Data with SGN-35 in Hodgkin Lymphoma

More than 75 percent of patients treated in the study achieved tumor reductions across all dose levels evaluated, including four with partial responses. Twelve additional patients had stable disease and seven had progressive disease. Of the four patients with partial responses, three are continuing on study, including one patient who has been receiving treatment for more than seven months. SGN-35 has been generally well-tolerated and the maximum tolerated dose has not yet been defined. The majority of adverse events were Grade 1 and 2, and are consistent with antibody administration. Dose-escalation has continued to 2.7 milligrams per kilogram (mg/kg).

"These results are particularly encouraging given that relapsed or refractory Hodgkin lymphoma is difficult to treat, especially in patients who relapse after stem cell transplantation," said Anas Younes, M.D., Professor of Medicine and Director, Clinical and Translational Research in the Department of Lymphoma/Myeloma at MD Anderson Cancer Center, and presenting investigator of the phase I study. "There are no approved drugs in this setting and no curative therapies. The objective responses observed in this trial support further investigation of SGN-35 towards developing a treatment option to address this unmet medical need."

SGN-35 comprises an anti-CD30 antibody joined by an enzyme cleavable linker to a potent, synthetic drug payload, monomethyl auristatin E (MMAE), using Seattle Genetics' proprietary ADC technology. The ADC is designed to be stable in the bloodstream, but to release MMAE upon internalization into CD30-expressing tumor cells, resulting in a targeted cell-killing effect.

Data were reported on twenty three patients in the single-arm phase I clinical trial who received escalating doses of SGN-35 starting at 0.1 mg/kg up to 1.8 mg/kg administered every three weeks. Of the 23 patients, 21 had Hodgkin lymphoma, one had angioimmunoblastic T-cell lymphoma and one had anaplastic large cell lymphoma. Enrolled patients had received a median of three prior chemotherapies, with 78 percent having received a prior autologous stem cell transplant.

"These data not only demonstrate the therapeutic potential of SGN-35 in the treatment of Hodgkin lymphoma, but also underscore the impact that our ADC technology can have in empowering antibodies for the treatment of cancer," said Clay B. Siegall, Ph.D., President and Chief Executive Officer of Seattle Genetics. "Based on these encouraging data, we are continuing with dose-escalation and planning future studies with SGN-35 to optimize dose and schedule, both as a single-agent and in combination with other agents."

A downloadable copy of Seattle Genetics' SGN-35 poster will be available from the "Clinical" section of the company's website at www.seattlegenetics.com.

In addition to SGN-35, Seattle Genetics is developing two other proprietary ADC programs, SGN-75, an anti-CD70 ADC, and an anti-CD19 ADC. Both ADCs have demonstrated potent antitumor activity at well tolerated doses in preclinical cancer models.

Keywords: Adverse Drug Effect, Adverse Drug Event, Adverse Drug Reaction, Anticancer Therapy, Antitumor Activity, Clinical Trial Research, Drug Development, Genetics, Hematology, Large-Cell Lymphoma, Oncology, Stem Cell Research, Therapy, Treatment, Seattle Genetics Inc.

This article was prepared by Biotech Business Week editors from staff and other reports. Copyright 2007, Biotech Business Week via NewsRx.com.