Acologix Announces Results of
AC-100 Initial Feasibility Study for Treatment of Periodontal Disease

Hayward, Calif., July 24, 2006 – Acologix, Inc., a privately held biopharmaceutical company, announced today that it has completed a Phase II feasibility study of AC-100 for the treatment of periodontal defects. AC-100 is a novel synthetic peptide derived from an endogenous human protein produced by bone and dental cells.

AC-100 demonstrated a favorable safety profile but did not significantly regenerate more periodontal bone versus placebo because the dose evaluated in this study exceeded what researchers believe may be the optimal dose to effectively treat periodontal disease.

“We learned a lot from this initial Phase II study and believe additional Phase II studies will determine appropriate dosing of AC-100 in the periodontal setting,” said David M. Rosen, Ph.D., Senior Vice President, Research and Development at Acologix. “This novel approach clearly warrants further study in this and related conditions. Periodontal disease affects millions of people worldwide and causes chronic loss of bone and periodontal ligaments that support teeth, ultimately resulting in tooth loss.”

The study enrolled 40 patients in need of periodontal surgery to correct existing periodontal defects. Defects were treated with a single dose of AC-100 or placebo (saline) delivered in a collagen sponge, and patients were followed for six months. The trial assessed the safety of AC-100 and its effect on periodontal bone and other soft tissue regeneration. The use of a novel and highly sensitive dental computed tomography (CT) instrument for measuring bone regeneration parameters also was evaluated and compared with traditional clinical measurement techniques, which include follow-up periodontal surgery.

“There was a high correlation between the bone regeneration parameters measured by CT and follow-up surgery suggesting that we may be able to greatly simplify and expedite future trials by eliminating the need for a second surgical procedure to assess bone regeneration,” added Dr. Rosen.

Earlier this year, clinical results of a separate Phase II study of AC-100 as a biological approach to treating tooth defects (prepared cavities) were presented at the annual meeting of the International Association for Dental Research (IADR) in Brisbane, Australia. That trial 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. AC-100 also demonstrated a favorable safety profile in that study.

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 on the development and commercialization of TRK-820 for the treatment of uremic pruritus in dialysis patients. TRK-820 is being studied in a European Phase 3 pivotal clinical trial, and a Phase III trial is planned in the United States. AC-100 (Dentonin®), a novel small peptide with dental, periodontal and orthopedic applications, has been studied in two recently concluded Phase II clinical studies, one in dental restoration procedures and another for the repair of periodontal defects, and further studies are currently planned. 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.

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’ business.

Acologix Contact

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