By Lisa Seachrist

Washington Editor

WASHINGTON — Oral care medicine specialist OraPharma Inc. completed a private placement worth $16 million with new and existing investors.

The privately held firm will use the funds to shepherd its lead adjunctive therapy for patients with adult periodontitis through Phase III clinical trials, as well as to further research and development of four other oral-care products.

"We are very pleased with our lineup of investors," said Michael Kishbauch, president and CEO of Warmington, Pa.-based OraPharma. "This is not a market where capital is readily available. Investors are, in general, more careful about investing in reality, not just promise."

Kishbauch said that the investment was roughly split between new and existing investors.

The first order of business for OraPharma will be the completion of the Phase III trial of its lead product, a controlled-release formulation of minocycline for local delivery in the mouth. Kishbauch told BioWorld Today the company hopes to file a new drug application before the end of next year.

The minocycline periodontal therapeutic system (MPTS) is a micronized version of minocycline powder microencapsulated into bioresorbable polymer microspheres. It is designed to be used in the treatment of periodontal disease, a progressive infection of the gums and surrounding tissues that affects an estimated 50 million Americans. The condition is caused by the build-up of bacteria known as dental plaque.

As the disease progresses, the gums separate from the teeth to form pockets, which helps the plaque spread below the gum line. Without treatment, the immune system's attempts to clear the bacterial buildup destroy the soft tissue and bone that hold the teeth. Periodontal disease is the leading cause of tooth loss in adults.

MPTS is designed to be used as an adjunctive therapy to the current standard of care, which is scaling and root planing: the mechanical removal of plaque lodged below the gum line. MPTS is placed in the periodontal pocket after scaling and root planing, where it adheres to the gums and delivers minocycline over 14 days.

"Scaling and root planing is a very aggressive procedure, [and] if we can extend the value of that treatment with MPTS, that is very important," Kishbauch said.

Kishbauch said delivering minocycline helps stall the progression of periodontal disease for several reasons. First, it is an antibiotic. Second, minocycline inhibits collagenase, lessening the destruction of the gums. Also, the drug promotes the reattachment of gum to root.

Lead Product Competes With Atridox

Should MPTS gain approval, it will face stiff competition from Ft. Collins, Colo.-based Atrix Laboratories Inc.'s Atridox, a polymer-based formulation of doxycycline, an antibiotic in the same class as minocycline. Atridox won FDA approval in September.

"I think it's fair to say that we will compete for the same general market," Kishbauch said. "The two products are similar in design and strategy. We believe there will be certain advantages over Atridox that will make MPTS beneficial to both patients and practitioners."

Kishbauch said MPTS would likely be more convenient to deliver for the dentist, and certain patients may simply respond better to one antibiotic over the other.

OraPharma issued Series C stock to a group of existing and new investors. Existing investors included Oak Investment Partners, of Westport, Conn.; Canaan Partners, of Rowayton, Conn.; Frazier & Co., of Seattle; and TL Ventures, of Wayne, Pa. New investors were led by Domain Associates, of Princeton, N.J., and included SenMed Medical Ventures, of Cincinnati; Biotechnology Investments Ltd., of London; and the Swedish venture fund HealthCap KB, of Stockholm. *