• E-mail
• Print
• Comment
• Font Size
• Digg
• del.icio.us
• Discuss article

Seattle Genetics Provides Update on SGN-15 Phase II Clinical Program at the World Conference on Lung Cancer

Posted on: Wednesday, 6 July 2005, 09:01 CDT

Seattle Genetics, Inc. (Nasdaq:SGEN) today reported data from its phase II clinical trials of SGN-15 at the 11th World Conference on Lung Cancer being held in Barcelona, Spain. Although the data show an encouraging trend, the company has decided to discontinue development of SGN-15, a first-generation antibody-drug conjugate (ADC), to focus on advancing its other pipeline programs and second-generation ADC technology. Seattle Genetics currently has two product candidates in clinical trials, SGN-30 and SGN-40, as well as multiple preclinical programs, including two that are expected to enter clinical trials over the next twelve months, SGN-35 and SGN-33, and two that are IND candidates in 2007, SGN-70 and SGN-75.

The phase II studies presented at the World Conference on Lung Cancer were designed to assess the optimal dosing schedule of SGN-15 in combination with Taxotere, a chemotherapy treatment, in patients with non-small cell lung cancer (NSCLC). The data suggest that the administration of SGN-15 three days prior to Taxotere results in greater synergy and drug effect than when the combination is administered simultaneously.

"Our clinical data confirm what we observed in our preclinical studies, which indicated that dosing SGN-15 prior to Taxotere enhances the therapeutic effect of the combination as compared to concurrent administration," said Clay B. Siegall, Ph.D., President and Chief Executive Officer at Seattle Genetics. "However, given the strength and diversity of the other products in our pipeline, we have decided not to continue development of SGN-15 and instead will evaluate out-licensing opportunities for the program."

"This decision enables us to focus our resources and development activities on advancing the many other promising programs in our pipeline. We are particularly excited about our lead clinical programs, SGN-30 and SGN-40, as well as SGN-33, a humanized anti-CD33 antibody that we plan to move into clinical trials before the end of 2005," Dr. Siegall added. "In addition, we are making continued progress with our industry-leading second-generation ADC technology, which utilizes stable, enzyme-cleavable linkers to target highly potent auristatin derivatives to tumor cells. We employ this second-generation ADC technology in our SGN-35 and SGN-75 product candidates, as well as partner the technology with leading biotechnology and pharmaceutical companies such as Genentech, CuraGen, Bayer, MedImmune and, most recently, PSMA Development Company."

About the SGN-15 Phase II Studies

SGN-15 is a first-generation antibody-drug conjugate (ADC) that utilizes a hydrazone linker to target the cell-killing drug doxorubicin to tumor tissues expressing a Lewis-Y-related antigen. During 2004, Seattle Genetics completed a randomized 60-patient phase II study of SGN-15 in NSCLC patients who had failed front-line therapy. Two-thirds of the patients received the combination of SGN-15 and Taxotere and one-third received Taxotere alone. In this study, patients on the combination arm received SGN-15 and Taxotere simultaneously. As previously reported, final data from this study demonstrated that patients receiving SGN-15 in combination with Taxotere had a median overall survival of 7.3 months, compared to 5.9 months for patients receiving Taxotere alone. Predicted overall survival at one year and 18 months for patients receiving the combination therapy was 29 percent and 18 percent, respectively, compared to 24 percent and 8 percent, respectively, for patients receiving Taxotere alone.

While the randomized phase II study was ongoing, the company generated additional preclinical data suggesting that dosing SGN-15 several days prior to Taxotere could improve the antitumor activity of the combination therapy. To evaluate the impact of dosing schedule on clinical efficacy, Seattle Genetics recently conducted two open label phase II studies of SGN-15 plus Taxotere in NSCLC patients who had failed front-line or front-line and second-line therapies. The trials were primarily designed to compare the uptake of a biomarker (FDG) as measured by positron emission tomography (PET) imaging in patients receiving SGN-15 plus Taxotere either simultaneously or sequentially. This approach was used to determine the relative activity of the two dose schedules on an expedited basis prior to obtaining a difference in patient survival.

One half of the patients in the PET trials received SGN-15 three days prior to Taxotere and the other half received the combination simultaneously. Fourteen patients have been treated in the U.S.-based study and 38 patients have been treated in a parallel study conducted in Russia. PET scans were analyzed by quantitative assessment of tumor standard update value (SUV) to measure metabolic activity of the primary tumor before and after treatment. Data from both studies suggest an advantage for patients receiving sequential dosing. In the U.S. study, of the first six evaluable patients, those receiving sequential dosing demonstrated an average decrease in SUV of 25 percent, compared to an average decrease of eight percent in patients receiving simultaneous dosing. In the Russian study, of 32 evaluable patients, those receiving sequential dosing demonstrated an average decrease in SUV of 32 percent, compared to 23 percent for patients receiving simultaneous dosing. The combination was well tolerated with both dosing schedules.

About Seattle Genetics

Seattle Genetics is a biotechnology company focused on the development of monoclonal antibody-based therapies for the treatment of cancer and immunologic diseases. The company is conducting clinical and preclinical development of a diverse portfolio of product candidates in a variety of oncology and immunology settings. In addition, Seattle Genetics has developed proprietary antibody-drug conjugate (ADC) technology comprised of highly potent synthetic drugs and stable linkers for attaching the drugs to monoclonal antibodies. The company currently has license agreements for its ADC technology with a number of leading biotechnology and pharmaceutical companies, including Genentech, Bayer, CuraGen and MedImmune. More information about Seattle Genetics' pipeline and technologies can be found at www.seattlegenetics.com.

Certain of the statements made in this press release are forward-looking. Actual results or developments may differ materially from those projected or implied in these forward-looking statements. Specifically, statements regarding the therapeutic potential and ongoing and planned clinical trials of Seattle Genetics' products candidates and ADC technology are forward-looking and actual results may differ materially from these statements for various reasons. Factors that may cause such a difference include risks related to adverse clinical results as our product candidates move into and advance in clinical trials, risks that our drug candidates do not provide improved response rates for cancer patients and failure by Seattle Genetics to secure collaborators necessary for the advancement of our drug candidates and technologies. 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.

Source: Business Wire

More News in this Category