Acologix Phase II Study of AC-100 (DENTONIN®) Meets Goal of Stimulating New Dentin Formation with Favorable Safety Profile in Novel Dental Application

-- Data presented in “Late Breaking News Session” at American Association for Dental Research Annual Meeting --

ORLANDO, Fla. and HAYWARD, Calif., March 10, 2006 – Acologix, Inc., a privately-held biopharmaceutical company, announced today that a Phase II clinical trial of AC-100 (Dentonin®), a novel synthetic peptide derived from an endogenous human protein produced by bone and dental cells, met its primary goal of stimulating the formation of new dentin (the hard tissue of teeth that protects the tooth pulp and supports the outer enamel) when applied directly to tooth defects (prepared cavities). AC-100 also demonstrated a favorable safety profile. The results were presented in the “Late-Breaking News Session” at the 35th Annual Meeting of the American Association for Dental Research (AADR) in Orlando.

Each year, more than 200 million dental restoration procedures are performed in the United States. Drilling during these procedures irritates the dental pulp and reduces the dentin layer that protects the pulp, causing pain and sensitivity, and sometimes leading to complications, including tooth loss.

“This Phase II clinical study demonstrates that a novel biological approach to dentistry, by modulating normal cell functions to stimulate the innate biological defenses of the tooth, can be introduced as a supplement to routine dental care,” said Cornelis H. Pameijer, D.M.D., D.Sc, Ph.D., study author and professor emeritus of prosthodontics at the University of Connecticut, School of Dental Medicine. “What is truly exciting are the many possible uses of AC-100 that could cover a broad range of applications in dentistry.”

Phase II Study Design and Results
The randomized, double-blind, placebo-controlled trial enrolled 35 patients who were candidates for at least two third-molar (wisdom teeth) extractions. Patients served as their own controls,
with one molar treated with 200 µg AC-100 (applied on days 0, 2 and 4 through the dentin tubules) and the other with a placebo. After two months, the teeth were extracted and evaluated for remaining dentin thickness (RDT), new dentin formation, inflammation and necrosis.
Administration of AC-100 resulted in a clear trend in the formation of new dentin compared to placebo. This effect was seen across a wide variety of cavity depths. Importantly, the efficacy of AC-100 was seen most dramatically in the deepest cavities (RDT < 0.5 mm), where the clinical utility of the approach is most needed. AC-100 was well tolerated in the study with no increase in inflammatory response, necrosis, pulpitis (inflammation of the pulp) or other complications observed in AC-100-treated teeth compared with placebo-treated teeth. No serious adverse events were reported.

“We learned a lot from this trial, and, based on these promising results, plan to meet with the FDA regarding future development as soon as possible,” said David M. Rosen, Ph.D., Vice President, Research and Development, at Acologix. “Because of its unique hard tissue regenerating properties and pulp-protective effects, we believe that AC-100 could be a promising treatment for patients undergoing a wide range of dental restoration procedures and could change the way that dentistry is practiced in the future.”

In addition to dental applications, Acologix is also studying AC-100 for periodontal, oral bone, dental implant and orthopedic applications. Phase II study results of AC-100 used in periodontal surgery are expected later this year.

About Acologix, Inc.

Acologix, a privately held biopharmaceutical company, is developing and commercializing innovative biopharmaceuticals targeting osteo-renal diseases, including chronic kidney disease, renal osteodystrophy, bone repair and regeneration, periodontal disease, general dentistry and oral care. Acologix is partnering with Toray Industries, Inc. of Japan on the development and commercialization of AC-820 (or TRK-820) for the treatment of uremic pruritus in dialysis patients. AC-820 is being studied in a European Phase III pivotal clinical trial, with a Phase III trial scheduled to launch in the United States in the second half of 2006. AC-100 (Dentonin®), a novel small peptide with dental, periodontal and orthopedic applications, is currently being studied in two Phase II clinical studies, one in dental restoration procedures and another for the repair of periodontal defects. Acologix is also developing AC-200 (Phosphatonin) to treat hyperphosphatemia and subsequent clinical problems associated with chronic kidney disease. For more information go to www.acologix.com

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Abstract #2225: “AC-100, Novel Biological Approach to Promoting Dentin Formation in Humans,” by Mirella Lazarov, D.D.S., Ph.D., David M. Rosen, Ph.D., and Jere D. Fellmann, Ph.D., of Acologix; Pamela DenBesten, D.D.S., M.S., of the University of California, San Francisco, School of Dentistry; and Cornelis Pameijer, D.M.D., D.Sc., Ph.D., of the University of Connecticut, School of Dental Medicine. Presented by Dr. Lazarov on Friday, March 10, at the American Association for Dental Research Annual Meeting in Orlando.

This press release contains “forward-looking” statements. These statements involve risks and uncertainties, which may cause results to differ materially from those set forth in the statements. The forward-looking statements include statements regarding product development and cannot be guaranteed. Acologix undertakes no obligation to publicly update any forward-looking statement, whether as a result of new information, future events, or otherwise. Forward-looking statements in this press release should be evaluated together with the many uncertainties that affect Acologix’s business.

Acologix Contact

Yoshi Kumagai
President and CEO
Phone: 510-512-7200
Fax: 510-786-1116
ir-usa@acologix.com