June 20, 2005

Advancis and Par have issued negative results of a phase III trial of their investigational antibiotic Amoxicillin PULSYS, for the treatment of Group A streptococcal pharyngitis/tonsillitis. Trial data failed to meet their primary non-inferiority endpoint, with 76.6% of patients achieving bacterial eradication at the end of treatment, compared to 88.5% of subjects receiving penicillin. Secondary non-inferiority endpoints were also missed, including clinical cure at the test-of-cure visit and bacterial eradication at the late post-therapy visit. This open-label study enrolled 353 patients, who received either 775 mg Amoxycillin PULSYS once-daily for seven days or 250 mg penicillin VK four times daily for ten day. The companies anticipate that these results will delay NDA filing by at least 1 year.