Adolor Corporation Reports That the FDA Has Requested Additional Data for Its Delta Opioid Agonist IND.

EXTON, Pa. -- Adolor Corporation (NASDAQ:ADLR) announced today that the U.S. Food and Drug Administration (FDA) has placed the Investigational New Drug Application (IND) for ADL5859, a novel, oral compound that targets the Delta opioid receptor, on clinical hold pending additional preclinical safety studies and additional information regarding the Company's proposed Phase 1 protocol. Until this data is compiled and submitted, the Company will be unable to initiate human clinical trials on this compound. Adolor filed the IND with the FDA on December 29, 2005.

"We intend to conduct the additional preclinical safety studies and address the issues raised by FDA regarding the proposed protocol as expeditiously as possible so that we may initiate our clinical development program with ADL5859," said James Barrett, Ph.D., senior vice president, chief scientific officer and president, research of Adolor Corporation. "We expect that it will take approximately 6 months to submit the requested information to the FDA."

About Adolor Corporation

Adolor Corporation (NASDAQ:ADLR) is a biopharmaceutical company specializing in the discovery, development and commercialization of novel prescription pain management products. Entereg(R) (alvimopan) is Adolor's lead product candidate under development for the management of the gastrointestinal side effects associated with opioid use. Adolor and GlaxoSmithKline (GSK) are collaborating in the worldwide development and commercialization of Entereg(R) in multiple indications. Adolor is developing a sterile lidocaine patch which is in Phase 2 clinical development for post-surgical incisional pain. Adolor also has a number of discovery research programs focused on the identification of novel compounds for the treatment of pain. By applying its knowledge and expertise in pain management, along with ingenuity, Adolor Corporation is seeking to make a positive difference for patients, caregivers and the medical community. For more information, visit www.adolor.com.

This release, and oral statements made with respect to information contained in this release, constitute forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. Such forward-looking statements include those which express plan, anticipation, intent, expectation, contingency, goals, targets or future development and/or otherwise are not statements of historical fact. These statements are based upon management's current expectations and are subject to risks and uncertainties, known and unknown, which could cause actual results and developments to differ materially from those expressed or implied in such statements. Such known risks and uncertainties relate to, among other factors: the risk that submission of the additional preclinical safety studies takes longer than six months; the risk that the additional preclinical safety studies and Phase I protocol data and information are not adequate for FDA to remove the clinical hold on the ADL 5859 IND; the costs, delays and uncertainties inherent in scientific research, drug development, clinical trials and the regulatory approval process; Adolor's history of operating losses since inception and its need for additional funds to operate its business; Adolor's reliance on its collaborators, including GlaxoSmithKline in connection with the development and commercialization of Entereg(R); market acceptance of Adolor's products, if regulatory approval is achieved; competition; and securities litigation.

Further information about these and other relevant risks and uncertainties may be found in Adolor's Reports on Form 8-K, 10-Q and 10-K filed with the U.S. Securities and Exchange Commission. Adolor urges you to carefully review and consider the disclosures found in its filings which are available in the SEC EDGAR database at http://www.sec.gov and from Adolor at http://www.adolor.com. Given the uncertainties affecting pharmaceutical companies in the development stage, you are cautioned not to place undue reliance on any such forward-looking statements, any of which may turn out to be wrong due to inaccurate assumptions, unknown risks, uncertainties or other factors. Adolor undertakes no obligation to (and expressly disclaims any such obligation to) publicly update or revise the statements made herein or the risk factors that may relate thereto whether as a result of new information, future events, or otherwise.