Response Genetics, Inc. Reports First Quarter 2009 Financial Results and Encouraging ResponseDX™ Sales Ramp

Business Wire, May 14, 2009

Response Genetics’ net loss for the first quarter ended 2009 was $3.3 million or $0.30 per share, compared with a net loss of $1.7 million, or $0.17 per share, for the same period last year.

Cash and Cash Equivalents

Cash and cash equivalents at March 31, 2009, were $10.2 million, compared to $9.5 million at December 31, 2008. As previously announced, Response Genetics completed an amended master service agreement with GlaxoSmithKline, Ltd. in December 2008. On January 5, 2009, the Company received payment of $1.3 million from GlaxoSmithKline related to the amended agreement.

Additionally, as previously announced, Response Genetics completed a private placement of 2 million newly issued common shares at a per-share price of $1.00. The Company received payment of $2.0 million from this private placement on March 2, 2009.

About Response Genetics, Inc.

Response Genetics, Inc. (“RGI”) (the “Company”) (Nasdaq: RGDX) is focused on the development and sale of molecular diagnostic tests for cancer. RGI’s technologies enable extraction and analysis of genetic information from genes derived from tumor samples stored as formalin-fixed and paraffin-embedded specimens. In addition to diagnostic testing services, RGI generates revenue from the sales of its proprietary analytical pharmacogenomic testing services of clinical trial specimens to the pharmaceutical industry. The Company was founded in 1999 and its principal headquarters are located in Los Angeles, California. For more information, please visit www.responsegenetics.com.

Forward-Looking Statement Notice

Except for the historical information contained herein, this press release and the statements of representatives of RGI related thereto contain or may contain, among other things, certain forward-looking statements, within the meaning of the Private Securities Litigation Reform Act of 1995.

Such forward-looking statements involve significant risks and uncertainties. Such statements may include, without limitation, statements with respect to the Company’s plans, objectives, projections, expectations and intentions, such as the ability of the Company, to analyze cancer samples, the potential for using the results of this research to develop diagnostic tests for cancer, the usefulness of genetic information to tailor treatment to patients, the ability of the Company to expand its ResponseDX: Lung™ and ResponseDX: Colon™ tests , and other statements identified by words such as “projects,” “may,” “could,” “would,” “should,” “believes,” “expects,” “anticipates,” “estimates,” “intends,” “plans” or similar expressions.

These statements are based upon the current beliefs and expectations of the Company’s management and are subject to significant risks and uncertainties, including those detailed in the Company’s filings with the Securities and Exchange Commission. Actual results, including, without limitation, actual sales results, if any, or the application of funds, may differ from those set forth in the forward-looking statements. These forward-looking statements involve certain risks and uncertainties that are subject to change based on various factors (many of which are beyond the Company’s control). The Company undertakes no obligation to publicly update forward-looking statements, whether because of new information, future events or otherwise, except as required by law.