Impax Pharmaceuticals, the branded products division of Impax Laboratories, Inc. (NASDAQ: IPXL), announced the successful filing of an Investigational New Drug Application (IND) for IPX159 in Restless Legs Syndrome (RLS) and initiated a Phase I study. The Company will test multiple formulations of IPX159 in this Phase I study in healthy volunteer subjects. The Company plans to start a Phase IIb study in RLS patients in the fourth quarter of 2011 after selection of a preferred formulation. “We are pleased to announce progress in our neurology pipeline, with the start of the Phase I study of IPX159 and we look forward to continued development of this compound in RLS,” said Suneel Gupta, Ph.D., chief scientific officer, Impax Pharmaceuticals. About IPX159 IPX159 is an oral controlled-release formulation of a small molecule with a unique mechanism of action in RLS. IPX159 is a new molecular entity in the US. The compound has an established pharmacologic and safety profile for non-RLS use outside the US and Impax has completed a proof of concept study in RLS. About Restless Legs Syndrome Restless Legs Syndrome (RLS) is a condition characterized by an irresistible urge to move ones’ limbs, most commonly the legs, to stop uncomfortable sensations and is associated with sleeping abnormalities, somnolence, pain and discomfort. There are about 25 million RLS sufferers in the US and an estimated current market size of $800 million. About Impax Laboratories, Inc. Impax Laboratories, Inc. is a technology-based specialty pharmaceutical company applying its formulation expertise and drug delivery technology to the development of controlled-release and specialty generics in addition to the development of branded products. Impax markets its generic products through its Global Pharmaceuticals division and markets its branded products through the Impax Pharmaceuticals division. Additionally, where strategically appropriate, Impax has developed marketing partnerships to fully leverage its technology platform. Impax is headquartered in Hayward, California, and has a full range of capabilities in its Hayward, Philadelphia and Taiwan facilities. For more information, please visit the Company's Web site at: www.impaxlabs.com. " Safe Harbor" statement under the Private Securities Litigation Reform Act of 1995: To the extent any statements made in this news release contain information that is not historical, these statements are forward-looking in nature and express the beliefs and expectations of management. Such statements are based on current expectations and involve a number of known and unknown risks and uncertainties that could cause the Company’s future results, performance or achievements to differ significantly from the results, performance or achievements expressed or implied by such forward-looking statements. Such risks and uncertainties include, but are not limited to, the effect of current economic conditions on the Company’s industry, business, financial position and results of operations, the ability to maintain an effective system of internal control over financial reporting, fluctuations in revenues and operating income, the ability to successfully develop and commercialize pharmaceutical products, reductions or loss of business with any significant customer or a reduction in sales of any significant product, the impact of competition, the ability to sustain profitability and positive cash flows, any delays or unanticipated expenses in connection with the operation of the Taiwan facility, the effect of foreign economic, political, legal and other risks on operations abroad, the uncertainty of patent litigation, consumer acceptance and demand for new pharmaceutical products, the difficulty of predicting Food and Drug Administration filings and approvals, the inexperience of the Company in conducting clinical trials and submitting new drug applications, the ability to successfully conduct clinical trials, reliance on alliance and collaboration agreements, the availability of raw materials, the ability to comply with legal and regulatory requirements, the regulatory environment, the ability to protect the Company’s intellectual property, exposure to product liability claims and other risks described in the Company’s periodic reports filed with the Securities and Exchange Commission. Forward-looking statements speak only as to the date on which they are made, and Impax undertakes no obligation to update publicly or revise any forward-looking statement, regardless of whether new information becomes available, future developments occur or otherwise.