CollaGenex Pharmaceuticals is Denied Motion for Preliminary Injunction Seeking to Prevent Launch of Generic Forms of Periostat.

NEWTOWN, Pa. -- CollaGenex Pharmaceuticals, Inc. (Nasdaq:CGPI) today announced that its motion seeking a temporary restraining order and a preliminary injunction in the United States District Court for the Eastern District of New York had been denied. As a consequence, IVAX Pharmaceuticals Inc. and CorePharma LLC ("Defendants") are free to continue to sell their generic equivalents of Periostat(R).

Colin Stewart, president and chief executive officer of CollaGenex, said: "We intend to continue to prosecute these lawsuits and seek compensation for profits lost as a result of the sale of infringing products. Meanwhile, we remain fully committed to executing our plans to develop our dermatology business."

CollaGenex Pharmaceuticals, Inc. is a specialty pharmaceutical company that has built its reputation on providing innovative medical therapies to the dental and dermatology markets. CollaGenex currently sells Periostat(R) as the first pharmaceutical to treat periodontal disease by inhibiting the enzymes that destroy periodontal support tissues and by enhancing bone protein synthesis. The Company also markets Atridox(R), Atrisorb FreeFlow(R) and Atrisorb-D FreeFlow(R), which are products of QTL USA, Inc., the successor to Atrix Laboratories, Inc., for the treatment of adult periodontitis. CollaGenex's professional dermatology sales force markets Pandel(R) (a prescription topical corticosteroid licensed from Altana, Inc.), Alcortin(TM) (1% iodoquinol and 2% hydrocortisone, a prescription topical antifungal steroid combination licensed from Primus Pharmaceuticals Inc.) and Novacort(TM) (2% hydrocortisone acetate and 1% pramoxine HCl, a prescription topical steroid and anesthetic licensed from Primus Pharmaceuticals Inc.)

Research has shown that certain tetracyclines can be chemically modified to retain non-antibiotic properties that may make them effective in treating diseases involving inflammation and/or destruction of the body's connective tissues. CollaGenex is evaluating various chemically modified tetracyclines (so called "IMPACS(TM)" compounds because they are Inhibitors of Multiple Proteases And CytokineS") to assess whether they are safe and effective in these applications. The Company has a pipeline of innovative product candidates with possible applications in dermatology and other disease states. In addition, CollaGenex has acquired the Restoraderm(TM) technology, a unique, proprietary dermal drug delivery system, and plans to develop a range of topical dermatological products with enhanced pharmacologic and cosmetic properties.

To receive additional information on the Company, please visit our Web site at www.collagenex.com, which does not form part of this press release.

Forward-Looking Statements

Statements in this press release regarding management's future expectations, beliefs, goals, plans or prospects, including statements relating to the Company's litigation, future products and the market for them, its future product development and introduction efforts, may constitute forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. CollaGenex' actual results could differ materially from those stated or implied in forward-looking statements due to a number of factors, including those factors contained in CollaGenex' most recent Quarterly Report on Form 10-Q for the quarter ended March 31, 2005 under the section "Additional Risks That May Affect Results" as well as other documents that may be filed by CollaGenex from time to time with the Securities and Exchange Commission. Forward-looking statements include statements regarding CollaGenex' expectations, beliefs, intentions or strategies regarding the future and can be identified by forward-looking words such as "anticipate", "believe", "could", "estimate", "expect", "intend", "may", "should", "will", and "would" or similar words. CollaGenex assumes no obligations to update the information included in this press release.

Periostat(R) is a registered trademark and Restoraderm(TM), and IMPACS(TM) are trademarks of CollaGenex Pharmaceuticals, Inc.

Novacort(TM) and Alcortin (TM) are trademarks of Primus Pharmaceuticals Inc.

Pandel(R) is a registered trademark of Taisho Pharmaceuticals.

Atridox(R), Atrisorb(R) and Atrisorb-D(R) are registered trademarks of QLT USA, Inc.