Adams Respiratory Therapeutics Receives Notice of Paragraph IV Certification Against Patents for Guaifenesin 600 mg Single-Ingredient Extended-Release Tablets

CHESTER, N.J., Aug. 21 Adams RespiratoryTherapeutics, Inc. (Nasdaq: ARxT) today announced that it has received aParagraph IV Certification Notice letter, advising that Perrigo R&D Co., hassubmitted an Abbreviated New Drug Application (ANDA) for guaifenesin 600 mgsingle-ingredient extended-release tablets.

Adams currently markets Mucinex SE, single-ingredient 600 mgextended-release guaifenesin, the only available FDA-approvedextended-release, single-ingredient guaifenesin product. In addition, Adams'portfolio of patent-protected, extended-release guaifenesin products includesMucinex DM and Mucinex D; and the Company recently launched a new line of 1200mg maximum strength extended-release guaifenesin products under the Mucinexname. None of these other products are the subject of this certificationletter. Adams has two patents that protect its suite of extended-releaseguaifenesin products and these patents are listed in the Food and DrugAdministration (FDA) Orange Book and expire in 2020.

Perrigo's certification letter sets forth allegations that Adams' U.S.Patents 6,372,252 and 6,955,821 are invalid and/or will not be infringed byPerrigo's manufacture, use or sale of the product for which the ANDA issubmitted, and reserves the right to raise unenforceability defenses.

Adams plans to vigorously defend its market position for single-entityMucinex as well as its patent portfolio protecting the Company's oral solid,extended-release guaifenesin products. Adams is evaluating Perrigo's noticeletter and has 45 days to commence a patent infringement lawsuit againstPerrigo that would automatically stay the FDA from approving Perrigo's ANDAfor 30 months or until a district court decision that is adverse to Adams,whichever may occur earlier.

About Adams Respiratory Therapeutics, Inc.

Adams is a specialty pharmaceutical company focused on the late-stagedevelopment, commercialization and marketing of over-the-counter andprescription pharmaceuticals for the treatment of respiratory disorders.

Forward-Looking Statements

This press release contains certain "forward-looking" statements,including Adams' defense of its exclusive market position for single-entityMucinex(R) and its patent portfolio. Such forward-looking statements can beidentified by the words "plans" and similar expressions and are subject torisks and uncertainties that could cause actual results to differ materiallyfrom those in the forward-looking statements. Factors that could cause actualresults to differ materially include, among others, the FDA's application ofthe same scientific standards to generic applicants as applied to the Adams'FDA approval of Mucinex(R) and Adams' ability to successfully defend itspatent position and protect its trade secrets and other proprietaryinformation; and other risk factors set forth under the and other risk factorsset forth under Item 1A. Risk Factors in the Company's Annual Report on Form10-K for the fiscal year ended June 30, 2006, and under Item 1A. Risk Factorsin the Company's Quarterly Report on Form 10-Q for the period ended March 31,2007. Except to the extent required by applicable securities laws, Adams isnot under any obligation to (and expressly disclaims any such obligation to)update its forward-looking statements, whether as a result of new information,future events, or otherwise. All statements contained in this press releaseare made only as of the date of this press release.

SOURCE Adams Respiratory Therapeutics, Inc.