CollaGenex Pharmaceuticals Announces Results of Phase 2 Dose-Finding Study of Incyclinide for the Treatment of Rosacea.

Company to Host Conference Call and Webcast Today at 9:00 a.m. Eastern Time

NEWTOWN, Pa. -- CollaGenex Pharmaceuticals, Inc. (NASDAQ:CGPI) today announced results of a Phase 2 dose-finding study designed to evaluate the safety and determine the therapeutic range of incyclinide for the treatment of rosacea. The Company will host a conference call and webcast today at 9:00 a.m. Eastern Time to discuss these results. Additional details about the call are provided below.

The primary clinical endpoint of the study was a reduction in inflammatory lesions in patients with rosacea. The study demonstrated that incyclinide was well-tolerated, with most adverse events being mild or moderate. However, the patients who were administered incyclinide did not demonstrate a greater reduction in inflammatory lesions than the patients on placebo at any time point during the study.

The double-blind, placebo-controlled trial enrolled a total of 197 moderate-to-severe rosacea patients at 19 centers. The patients were divided among four groups and administered either a placebo capsule or a 5 mg, 10 mg or 20 mg incyclinide capsule once a day for 12 weeks. All patients were evaluated by their physicians at weeks 3, 6, 9, 12 and 16.

Klaus Theobald, M.D., Ph.D., chief medical officer of CollaGenex, said, "We are surprised and disappointed that the results of this large, well-controlled Phase 2 study did not support the findings of an earlier, much smaller pilot study in rosacea patients. On the basis of these results, we will not be pursuing further clinical development of incyclinide in rosacea patients. However, based on its apparent efficacy in acne patients and its favorable side effect profile in doses up to 20 mg per day, we are planning to conduct additional development work in an acne indication for incyclinide."

Colin Stewart, president and chief executive officer of CollaGenex, stated, "While clinical disappointments are to be expected in pharmaceutical development, CollaGenex will continue to focus on developing its robust product pipeline. We recently announced outstanding clinical results in our large Phase 2 study of Col-118 in the treatment of erythema, and we expect to initiate Phase 3 clinical studies of Col-118 very early in 2008. In the first quarter of 2008, we also anticipate initiating Phase 2 studies of becocalcidiol for the treatment of psoriasis, and we will continue to study how we can maximize value from incyclinide."

Conference Call Information

CollaGenex will hold a conference call today, September 26, 2007, at 9:00 a.m. Eastern Time to discuss the results announced in this release. Investors and other interested parties may access the conference call by dialing 888-868-9079 in the U.S. or 973-935-8510 internationally, or via a live webcast on the company's website at www.collagenex.com.

For those who cannot listen to the live webcast, a replay will be available shortly after the call at www.collagenex.com for 90 days. Additionally, a recording of the call will be available by telephone until 11:59 p.m. on October 3, 2007 by dialing 877-519-4471 in the U.S. or 973-341-3080 internationally, and entering access code: 9276919.

About CollaGenex

CollaGenex Pharmaceuticals, Inc. is a specialty pharmaceutical company currently focused on developing and marketing innovative proprietary medical therapies to the dermatology market. In July 2006, CollaGenex launched Oracea(R), the first FDA-approved systemic product for the treatment of rosacea. CollaGenex also recently completed Phase 2 clinical trials to evaluate COL-118, a topical compound based on the SansRosa(TM) technology, for the treatment of erythema associated with rosacea. CollaGenex's professional dermatology sales force also markets Pandel(R), a prescription topical corticosteroid licensed from Altana, Inc., Alcortin(TM) (1% iodoquinol and 2% hydrocortisone), a prescription topical antifungal steroid combination, and Novacort(TM) (2% hydrocortisone acetate and 1% pramoxine HCl), a prescription topical steroid and anesthetic. Alcortin and Novacort are marketed by the Company under a Promotion and Cooperation agreement with Primus Pharmaceuticals, Inc.

Research has shown that new compounds can be created by chemically modifying certain tetracyclines and that these new compounds have properties that may make them effective in treating diseases involving inflammation and/or destruction of the body's connective tissues. CollaGenex is evaluating various of these compounds (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 SansRosa(TM) technology, which consists of a class of compounds that have shown promise in reducing the erythema associated with rosacea, and the Restoraderm(R) technology, a unique, proprietary dermal drug delivery system. In May, 2007 CollaGenex acquired a license from QuatRx Pharmaceutical Company to develop and commercialize becocalcidiol, a patented Vitamin D analogue currently in Phase II Clinical trials for the topical treatment of mild to moderate psoriasis. CollaGenex plans to leverage these platforms 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, intentions, goals, strategies, plans or prospects, including statements relating to the clinical results and commercial potential of incyclinide, may constitute forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. CollaGenex's 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 the most recent Form 10-Q for the quarter ended June 30, 2007 under the section "Risk Factors" 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's expectations, beliefs, intentions, goals, strategies, plans or prospects 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 or revise any forward-looking statements, whether as a result of new information, future events or otherwise.

Oracea (R) and Restoraderm(R) are registered trademarks and IMPACS(TM) and SansRosa(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.

All other trade names, trademarks or service marks are the property of their respective owners and are not the property of CollaGenex Pharmaceuticals, Inc. or any of our subsidiaries.