Replidyne, Inc. Announces Positive Phase I Results for Topical Antibiotic REP8839

LOUISVILLE, Colo., June 26 /PRNewswire-FirstCall/ -- Replidyne, Inc. today announced results from three Phase I trials studying REP8839, a novel topical antibiotic that has shown potent in vitro activity against major skin pathogens including methicillin-resistant S. aureus (MRSA). The results of the Phase I trials show that topically applied REP8839 appears safe, well-tolerated and associated with low systemic exposure, or drug absorption into the bloodstream, which is desirable for a topical antibiotic treatment. Based on these results, Replidyne plans to initiate Phase II trials in children with impetigo, the most common bacterial skin infection, by the end of the year.

"REP8839 is a promising development candidate and has the potential to be an important treatment option for physicians in the ongoing fight against drug-resistant infections including MRSA, a growing public health concern," said Kenneth J. Collins, Replidyne's President and Chief Executive Officer. "With these safety data, we intend to move forward into Phase II trials to study the safety and efficacy of REP8839 in patients with impetigo and other skin and wound infections."

REP8839 was tested in three Phase I trials which collectively enrolled over 400 subjects. In the first Phase I trial, safety, tolerability and skin irritancy were tested following repeated daily application of REP8839, at three drug concentrations (1%, 2% and 4%), on intact and abraded skin. Irritancy scores comparable to placebo were recorded for all REP8839 exposed test subjects. In the second study, in addition to safety, tolerability and dermal irritancy, systemic exposure was examined following repeated daily application of REP8839 on a larger surface area of intact and abraded skin. In all subjects, REP8839 was associated with low systemic exposure and low skin irritancy. In the third study, a 2% formulation of REP8839 was tested for its ability to cause long-term sensitization and irritancy. No sensitization reactions were recorded in any of the subjects, and low irritancy potential was confirmed. Additionally, in all Phase I studies no serious adverse events were observed in any study subject.

About REP8839

REP8839 is a novel topical antibacterial ointment that targets the bacterial methionyl tRNA (MetRS) enzyme. MetRS is an unexploited target in clinically-important Gram-positive bacteria and represents a promising platform for the development of new antibacterial agents with no cross-resistance to currently marketed antibiotics. In vitro, REP8839 is highly active against major skin pathogens such as Streptococcus pyogenes and Staphylococcus aureus (S. aureus), including drug-resistant strains such as MRSA, mupirocin-resistant and vancomycin-resistant S. aureus.

About Impetigo

Impetigo is a contagious skin disorder caused by bacterial infection and characterized by crusting, red skin lesions, most frequently affecting children. It is the third most common skin disease in children, causing peak incidence among those aged two to five years. Since 2004, the incidence of impetigo has increased 21 percent. In 2006, topical antibiotic prescriptions accounted for 48 percent of all impetigo treatments.

About Replidyne, Inc.

Replidyne is a biopharmaceutical company focused on discovering, developing, in-licensing and commercializing innovative anti-infective products. Replidyne's lead product, faropenem medoxomil, is a novel oral, community antibiotic, expected to be appropriate for use as a first-line antibiotic for treatment of respiratory and skin infections in adult and pediatric patients. Replidyne's second drug candidate, REP8839, is a topical anti-infective product candidate in development for the treatment of skin and wound infections, including methicillin-resistant S. aureus (MRSA) infections. Replidyne is also pursuing the development of other novel anti-infective products based on its in-house discovery research.

Safe Harbor

This press release contains plans, intentions, objectives, estimates and expectations that constitute forward-looking statements about Replidyne, Inc. that involve significant risks and uncertainties. Actual results could differ materially from those discussed due to a number of factors including, the success and timing of pre-clinical studies and clinical trials; the Company's ability to obtain and maintain regulatory approval of product candidates and the labeling under any approval that may be obtained; plans to develop and commercialize product candidates; the loss of key scientific or management personnel; the size and growth of the potential markets for the Company's product candidates and the Company's ability to serve those markets; regulatory developments in the U.S. and foreign countries; the rate and degree of market acceptance of any future products; the accuracy of Company estimates regarding expenses, future revenues and capital requirements; the Company's ability to obtain and maintain intellectual property protection for our product candidates; the successful development of the Company's sales and marketing capabilities; the success of competing drugs that are or become available; and the performance of third party manufacturers. These and additional risks and uncertainties are described more fully in the Company's Form 10-K filed with the SEC under the Securities Exchange Act of 1934. Copies of filings made with the SEC are available through the SEC's electronic data gather analysis and retrieval system (EDGAR) at www.sec.gov. All forward-looking statements made in the press release are made as of the date hereof and the Company assumes no obligation to update the forward-looking statements in the document.

CONTACT: Sabrina B. Oei, Dir. Investor & Public Relations of Replidyne,Inc., +1-303-996-5535

Web site: http://www.replidyne.com/