Affymetrix Announces New Cost-Effective Product for Standardizing Drug Metabolism Studies

Affymetrix, Inc. (Nasdaq:AFFX) today announced the DMET(TM) Plus Premier Pack, the most comprehensive method for standardizing drug metabolism studies. The DMET (Drug Metabolism Enzymes and Transporters) Plus Panel features the most biologically relevant content identified by key opinion leaders from industry and academia in a cost-effective format. The DMET Plus Panel contains markers in all FDA-validated genes(1) and covers more than 90 percent of the current ADME Core markers as defined by the PharmaADME group. It offers 1,936 high-value drug metabolism and transporter markers.

Researchers in the pharmacology of cancer therapies are already using the DMET Panel to better understand the toxicity of and response to chemotherapeutic agents. The comprehensive DMET Panel enabled John Deeken, M.D., from the Lombardi Comprehensive Cancer Center at Georgetown University, to find numerous genes potentially involved in cancer treatment decisions, in collaboration with Affymetrix.

“The DMET Panel allowed us to characterize the pharmacogenetics of the chemotherapeutic agents docetaxel and thalidomide in patients treated for prostate cancer in a Phase II clinical trial, demonstrating that the DMET Panel can be readily incorporated into cancer clinical trials,” said Dr. Deeken. “The breadth and depth of the DMET Panel provides a unique approach to determining genetic variations’ relevance across a drug’s metabolic pathway.”

“Affymetrix is the first company to deliver a comprehensive drug metabolism solution,” said Kevin King, president of Affymetrix. “In the U.S. alone, adverse drug reactions are the fourth most common cause of death, costing $100 billion.(2) With the DMET Plus Premier Pack, we are enabling industry, academic, and government researchers to identify the high-quality biomarkers that will enable them to ask broader questions and make better go-no-go clinical trial decisions.”

A recent study using the drug warfarin demonstrated the value of the unique DMET content. Warfarin is one of the top 10 drugs known to cause severe adverse events, including drug-related death. Researchers at the Marshfield Clinic discovered a new variant in CYP4F2 which explained 8 percent of dosing variability in select patient populations.(3) This biomarker is now being tested in a Phase III prospective trial.

The DMET Plus Premier Pack also offers software which enables customers to look only at the markers they want to genotype, or those that are allowed by patient consent. Data is automatically interpreted into the commonly used star allele format which can be easily integrated into clinical trial workflows. Using a translation table cuts the time needed for analysis from days to minutes.

For more information on the DMET Plus Premier Pack, please visit:

(1)Frueh, F.W., et al. Pharmacogenomic biomarker information in drug labels approved by the United States food and drug administration: prevalence of related drug use. Pharmacotherapy 28(8):992-998

(2) Pharmacogenomics Public Healthcare 2008 (market research report)

(3) Caldwell, M. D., et al. CYP4F2 genetic variant alters required warfarin dose. Blood 111(8):4106-12 (2008)

About Affymetrix

Affymetrix GeneChip(R) microarray technology is the industry-standard tool for analyzing complex genetic information. After inventing microarray technology in the late 1980s, Affymetrix scientists have been dedicated to developing innovative products that provide researchers with a more complete view of the genome. These products continue to accelerate genetic research and enable scientists to develop diagnostics and tailor treatments for individual patients by identifying and measuring the genetic information associated with complex diseases.

Today, Affymetrix technology is used by the world’s top pharmaceutical, diagnostic and biotechnology companies, as well as leading academic, government and not-for-profit research institutes. More than 1,800 systems have been shipped around the world and more than 14,000 peer-reviewed papers have been published using the technology.

Affymetrix is headquartered in Santa Clara, Calif., and has manufacturing facilities in Sacramento, Calif., Cleveland, Ohio, and Singapore. The company has about 1,100 employees worldwide and maintains sales and distribution operations across Europe and Asia. For more information about Affymetrix, please visit the company’s website at

Forward-looking Statements

All statements in this press release that are not historical are “forward-looking statements” within the meaning of Section 21E of the Securities Exchange Act as amended, including statements regarding Affymetrix’ “expectations,””beliefs,””hopes,””intentions,””strategies” or the like. Such statements are subject to risks and uncertainties that could cause actual results to differ materially for Affymetrix from those projected, including, but not limited to: risks and uncertainties relating to commercial success of the DMET Plus Premier Pack discussed in this press release; risks of the company’s ability to achieve and sustain higher levels of revenue, higher gross margins and reduced operating expenses; uncertainties related to technological approaches, manufacturing and product development; personnel retention; uncertainties related to cost and pricing of Affymetrix products; dependence on collaborative partners; uncertainties related to sole-source suppliers; risks associated with past and future acquisitions; uncertainties relating to FDA and other regulatory approvals; competition; risks relating to intellectual property of others and the uncertainties of patent protection and litigation. These and other risk factors are discussed in Affymetrix’ Form 10-K for the year ended December 31, 2007, and other SEC reports, including its Quarterly Reports on Form 10-Q for subsequent quarterly periods. Affymetrix expressly disclaims any obligation or undertaking to release publicly any updates or revisions to any forward-looking statements contained herein to reflect any change in Affymetrix’ expectations with regard thereto or any change in events, conditions or circumstances on which any such statements are based.

NOTE: Affymetrix, the Affymetrix logo and GeneChip(R) are registered trademarks owned or used by Affymetrix Inc.