Dose-Escalation Completed and Preliminary Antitumor Activity Observed
SANTA MONICA, Calif. & BOTHELL, Wash.--(BUSINESS WIRE)--Jun. 4, 2012--
Agensys, Inc., an affiliate of Tokyo-based Astellas Pharma Inc., and
Seattle Genetics, Inc. (Nasdaq: SGEN) today announced interim data from
a phase I clinical trial evaluating ASG-5ME for the treatment of
castration-resistant prostate cancer (CRPC). ASG-5ME is an antibody-drug
conjugate (ADC) targeting the SLC44A4 antigen that is being co-developed
by both companies for the treatment of solid tumors. The data are being
presented at the American Society of Clinical Oncology (ASCO) annual
meeting being held June 1-5, 2012 in Chicago, IL.
“SLC44A4 is an attractive target in prostate cancer and is present in
the majority of patients with both localized and metastatic disease,”
said Leonard Reyno, M.D., Senior Vice President and Chief Medical
Officer of Agensys. “The current Phase I data demonstrates the
tolerability of this antibody drug conjugate and further evaluation of
safety and antitumor activity in patients with castration resistant
prostate cancer is ongoing.”
“It is encouraging to observe these preliminary data with ASG-5ME in
prostate cancer, a disease for which late-stage patients need additional
therapeutic options,” said Jonathan Drachman, M.D., Senior Vice
President, Research and Translational Medicine of Seattle Genetics. “In
addition to prostate cancer, our two companies are continuing to
evaluate the potential use of ASG-5ME in other solid tumor indications.
In parallel, we are collaborating with Agensys to co-develop ASG-22ME,
an ADC targeting Nectin-4 for solid tumors.”
Phase 1 trial of ASG-5ME in metastatic castration-resistant prostate
cancer (CRPC) (Abstract #4568)
ASG-5ME is being evaluated in a
single-agent phase I clinical trial to determine the maximum tolerated
dose (MTD) and to assess the safety, pharmacokinetic profile and
antitumor activity of escalating doses of ASG-5ME. At the time of data
analysis, 26 patients were enrolled. The median age of the patients was
69.5 years and the median baseline prostate-specific antigen (PSA) level
was 82.25.
Key findings, presented by Dr. Michael Morris from Memorial Sloan
Kettering Cancer Center in New York, NY, and clinical investigator on
the study include:
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ASG-5ME was given to cohorts of patients with CRPC as a single IV
infusion every three weeks at doses ranging from 0.3 milligrams per
kilogram (mg/kg) to 3.0 mg/kg. The MTD was exceeded at 3.0 mg/kg.
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Across all dose cohorts, the most common Grade 1 and 2 adverse events
occurring in more than 20 percent of patients included fatigue (50.0
percent), decreased appetite (42.3 percent), peripheral neuropathy
(34.6 percent) and nausea (23.0 percent).
-
PSA reductions were observed in several patients, providing
preliminary evidence of antitumor effect with ASG-5ME treatment.
The phase I trial is ongoing, with enrollment to two expansion cohorts
in chemotherapy naïve and chemotherapy exposed CRPC patients planned.
Seattle Genetics and Agensys recently completed enrollment in a phase I
pancreatic cancer trial of ASG-5ME dosed weekly. The companies plan to
evaluate ASG-5ME in patients with gastric cancer based on preclinical
expression data.
About ASG-5ME
ASG-5ME is an ADC composed of a fully human
antibody directed to SLC44A4, a solute carrier antigen family member
identified by Agensys to be overexpressed in epithelial cancers,
including more than 80 percent of samples derived from patients with
prostate, pancreatic and gastric cancers. The antibody is attached to
monomethyl auristatin E (MMAE) via an enzyme-cleavable linker using
Seattle Genetics’ proprietary technology. The ADC is designed to be
stable in the bloodstream, but to release MMAE upon internalization into
SLC44A4-expressing tumor cells, resulting in targeted cell-killing.
Seattle Genetics and Agensys are co-developing and will globally
co-commercialize and share profits on a 50:50 basis for ASG-5ME and
ASG-22ME. Seattle Genetics also has an option for 50:50 cost and
profit-sharing of a third ADC program at the time of investigational new
drug submission.
About Agensys
Agensys, Inc., an affiliate of Astellas Pharma
Inc., is developing a pipeline of therapeutic fully human monoclonal
antibodies (MAbs) to treat cancer. The MAb product pipeline is being
generated to Agensys' diverse portfolio of proprietary, clinically
relevant cancer targets. Agensys' target portfolio and related products
are protected by a large patent estate. The company has full
capabilities to generate, develop and manufacture antibody products.
Agensys is progressing a pipeline of both naked and antibody-drug
conjugated (ADC) therapeutic antibodies, directed at a variety of cancer
indications, including those of the prostate, kidney, pancreas, ovary,
bladder, lung, colon, breast and skin. ADC products are based on drug
platform technologies developed by Seattle Genetics. Agensys is
developing a growing pipeline of clinical stage functional MAbs and ADC
products.
About Astellas
Astellas Pharma Inc., located in Tokyo,
Japan, is a pharmaceutical company dedicated to improving the health of
people around the world through the provision of innovative and reliable
pharmaceutical products. Astellas has approximately 17,000 employees
worldwide. The organization is committed to becoming a global category
leader in urology, immunology & infectious diseases, oncology,
neuroscience, DM complications & metabolic diseases. For more
information on Astellas Pharma Inc., please visit www.astellas.com/en.
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 U.S. Food and
Drug Administration granted accelerated approval of ADCETRIS®
(brentuximab vedotin) in August 2011 for two indications. ADCETRIS is
being developed in collaboration with Millennium: The Takeda Oncology
Company. In addition, Seattle Genetics has three other clinical-stage
ADC programs: SGN-75, ASG-5ME and ASG-22ME. Seattle Genetics has
collaborations for its ADC technology with a number of leading
biotechnology and pharmaceutical companies, including Abbott, Bayer,
Celldex Therapeutics, Daiichi Sankyo, Genentech, GlaxoSmithKline,
Millennium, Pfizer and Progenics, as well as ADC co-development
agreements with Agensys, an affiliate of Astellas, and Genmab. More
information can be found at www.seattlegenetics.com.
For Seattle Genetics:
Certain of the statements made in this press
release are forward looking, such as those, among others, relating to
further evaluation of ASG-5ME and the initiation of future 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 risk of adverse events as
ASG-5ME 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 March 31, 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.
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Source: Seattle Genetics, Inc.
Astellas
Jenny Kite, 847-682-4530
jenny.kite@us.astellas.com
or
Seattle
Genetics
Peggy Pinkston, 425-527-4160
ppinkston@seagen.com
