Arestin

Cardiac transplant patients had a significantly higher incidence of periodontal disease than patients with no history of heart disease involved in a recent study, according to data presented today at the 24th World Congress of Cardiology meeting in Sydney, Australia.

The study adds further evidence that periodontal disease - an infection of the gums - may be linked to more serious systemic illnesses. In the study, "Periodontitis: A New Cardiovascular Risk Factor," researcher Jan Lessem, M.D., Ph.D, FACC, and Chief Medical Officer and Executive Vice President Clinical Research of OraPharma, Inc. (Nasdaq: OPHM), tracked periodontal records of 82 cardiac transplant patients and a larger group of 962 patients with no history of heart disease. The study concluded that 77 percent of the transplant patients had periodontitis, compared with only 13 percent of the healthy patients.

"This study adds one more piece of significant evidence that, along with high cholesterol and blood pressure, periodontal disease should be seen as a risk factor for cardiovascular disease," Dr. Lessem said. "In recent decades, large epidemiological studies have demonstrated the potential link between periodontitis and ischemic heart disease in particular. This study only adds to a growing body of evidence."

For years, researchers have studied possible links between periodontitis and heart disease. Among the most recent studies was one published in the The Journal of Periodontology (February 2002) showing that diseased gums released significantly higher levels of bacterial pro-inflammatory components, such as endotoxins, into the bloodstream in patients with severe periodontal disease compared to healthy patients. As a result, these harmful bacterial components in the blood could travel to other organs in the body, such as the heart, and cause harm.

That study was in line with recent findings at the University of Buffalo, where researchers suggested periodontal disease may cause oral bacterial components to enter the bloodstream and trigger the liver to make C-reactive proteins, which are predictors for increased risk of cardiovascular disease.

In 2000, the first-ever Surgeon General's Report on Oral Health in America suggested that there are strong associations between oral infections--primarily periodontal infections--and other more serious diseases, such as heart disease, stroke, diabetes, and pre-term, low infant birth rate.

It is now common practice for dentists to prescribe antibiotics prior to oral surgery or even advanced cleaning techniques for patients with particular heart health profiles. Among the newer methods for administering antibiotics is the product Arestin(TM), which uses patented microsphere technology to deliver the antibiotic minocycline beneath the gum, directly into the infected periodontal pocket, after deep cleaning of the teeth and gums with a common method of treatment known as scaling and root planing.

In the current study, to ensure that data were not influenced by one particular geographical area, Dr. Lessem and his collaborators Connie Drisco, DDS; Rutger Persson, DDS, PhD; and Hubert N. Newman, ScD, FRCPath tracked cardiovascular patients in three centers: University of Louisville; University of Washington, Seattle; and Papworth Medical Center in collaboration with Parkside National Health Service Trust in London.

More than 50 million Americans are believed to suffer from periodontal disease, while less than 30 percent of those affected seek treatment. The culprit behind this oral disease is plaque, a sticky film containing bacteria that builds up on teeth. Poor oral health habits allow plaque to build up and harden under the gums that support the teeth. This invasion separates the gums from the teeth, leaving empty "pockets" which perpetuate the infection. If not properly treated, these infections cause gum inflammation and can lead to tooth loss.

In healthy teeth, bone and gum tissue fit snugly around the teeth. Periodontal disease, a bacterial infection, destroys the gums and bone that hold teeth in place, forming "pockets" around the teeth. Infection occurs when dental plaque accumulates on the surfaces of teeth, eventually spreading below the gumline into the "pockets." The bacteria in the plaque produce chemicals that can cause the gums to swell and bleed.

OraPharma, Inc., a specialty pharmaceutical company with an initial focus on the emerging field of oral health care, discovers, develops and commercializes therapeutics for oral health care, oncology and orthopedics. OraPharma's initial product, Arestin(TM), which represents a promising therapeutic advance for the adjunct treatment of periodontal disease, was approved for marketing by the FDA in February 2001 and launched on April 2, 2001. The Company's new product programs include a compound for the treatment of mucositis, a complication of cancer therapy, an agent for bone and tissue regeneration, as well as a new technology platform directed at an advanced system for the delivery of large-molecule drugs. In August 2001, the Company started a Phase 1 clinical trial for the mucositis product. In addition, the Company has earlier stage technological initiatives focused on a next-generation periodontal therapeutic and a dental trauma preparation.

Statements included in this press release that are not historical in nature are "forward-looking statements" within the meaning of the Private Securities Litigation Reform Act of 1995. These statements include statements regarding the Company's lead product, Arestin(TM). In addition, these statements include statements regarding new product development initiatives for mucositis, bone and tissue regeneration, a next-generation periodontal therapeutic and dental trauma. The Company cautions readers that forward-looking statements are subject to certain risks and uncertainties, which could cause actual results to differ materially. Such risks and uncertainties include the possible failure of clinical trials for the Company's product candidates in development; and other risks and factors identified from time to time in the Company's reports filed with the U.S. Securities and Exchange Commission. We claim the protection of the Safe Harbor for forward-looking statements contained in the Private Securities Litigation Reform Act of 1995. We disclaim any obligation to update the forward-looking statements in this press release.