CollaGenex Pharmaceuticals Reports Positive Outcome of Phase II Clinical Study Evaluating Metastat in Kaposi's Sarcoma

[CollaGenex Pharmaceuticals via BizWire]

NEWTOWN, Pa.--(BUSINESS WIRE)--April 30, 2004--CollaGenex
Pharmaceuticals, Inc. (Nasdaq:CGPI) today announced the interim
results of a Phase II multicenter, open label and randomized clinical
study evaluating the safety and efficacy of its investigational
product, Metastat(R) (Col-3), for the treatment of HIV-related
Kaposi's sarcoma.
This Phase II study is conducted under a CRADA between CollaGenex
and the National Cancer Institute ("NCI"). The principal investigator
is Bruce Dezube, M.D., of Beth Israel Deaconess Medical Center at the
Harvard Medical School. Seventy five patients were randomized to
receive Col-3 at a dose of either 50 mg or 100 mg per day. The study
is still ongoing with 12 patients in the low dose group and 10
patients in the high dose group who have been in the study for more
than 2 years.
The interim analysis showed a response rate of 38% in the low dose
group and 26% in the high dose group, confirming the tumor activity
described previously in the Phase I trial. While the median time to
response was comparable in both dose groups, patients in the higher
dose group had a markedly prolonged duration of remission. Also, the
study confirmed the previous finding that median levels of circulating
MMP-2 (gelatinase A) levels are reduced with higher dosing.
"I am particularly encouraged by the fact that patients can
tolerate Col-3 long term and that we observed meaningful tumor
shrinkage, including complete resolution of tumors," noted Dr. Dezube.
"This favorable efficacy to risk ratio leads me to conclude that a
Phase III trial is warranted."
"The results from this Phase II clinical study indicate that
Metastat potentially offers significant benefits for Kaposi's sarcoma
patients," said Colin Stewart, chairman, president and chief executive
officer of CollaGenex. "Our next step will be to meet with the NCI to
review the data and plan how we will move forward to capitalize on
this opportunity to make a new treatment available for patients with
Kaposi's sarcoma."

About CollaGenex

CollaGenex Pharmaceuticals, Inc. is a specialty pharmaceutical
company focused on providing innovative medical therapies to the
dental and dermatology markets. Currently, the Company's professional
dental pharmaceutical sales force markets Periostat(R), which is
indicated as an adjunct to scaling and root planing for the treatment
of adult periodontitis. Periostat is the first and only pharmaceutical
to treat periodontal disease by inhibiting the enzymes that destroy
periodontal support tissues, and by enhancing bone protein synthesis.
The dental sales force also promotes Atridox(R), Atrisorb FreeFlow(R)
and Atrisorb-D FreeFlow(R), Atrix Laboratories, Inc.'s products for
the treatment of adult periodontitis, to the dental market. The
Company's professional dermatology sales force markets Pandel(R), a
prescription topical corticosteriod licensed from Altana, Inc.
Research has shown that certain unique properties of the
tetracyclines discovered during the development of Periostat(R) may be
applicable to other diseases involving inflammation and/or destruction
of the body's connective tissues, including acne, rosacea,
meibomianitis and cancer metastases, among others. CollaGenex is
further evaluating Periostat(R), as well as the new IMPACS(R)
compounds, to assess whether they are safe and effective in these
applications. In addition, CollaGenex has licensed the Restoraderm(R)
technology, a unique, proprietary dermal drug delivery system, in
order 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.
This press release contains forward-looking statements within the
meaning of Section 21E of the Securities and Exchange Act of 1934, as
amended. Investors are cautioned that forward-looking statements
involve risks and uncertainties, which may affect the Company's
business and prospects. The Company's business of selling, marketing
and developing pharmaceutical products is subject to a number of
significant risks, including risks relating to the implementation of
the Company's sales and marketing plans for Periostat and other
products that we market, risks associated with enforcement of our
intellectual property rights, risks inherent in research and
development activities, risks associated with conducting business in a
highly regulated environment and uncertainty relating to clinical
trials of products under development, all as discussed in the
Company's periodic filings with the U.S. Securities and Exchange
Commission.

Periostat(R), IMPACS(R), Metastat(R) and Restoraderm(R) are
registered trademarks of CollaGenex Pharmaceuticals, Inc.
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.
Pandel(R) is a trademark of Taisho Pharmaceuticals.
Atridox(R), Atrisorb(R) and Atrisorb-D(R) are registered
trademarks of Atrix Laboratories, Inc.