Treatment of vancomycin-resistant Enterococcus faecium infections with quinupristin/dalfopristin

Clinicians caring for patients with vancomycin-resistant Enterococcus faeci um (VREF) infections face severe constraints in the selection of treatment. Quinupristin/dalfopristin (Synercid) is active in vitro against VREF, with a MIC90 of 1.0 mug/mL. We investigated the clinical efficacy and safety of this agent in a multicenter, prospective, noncomparative, emergency-use st udy of 396 patients. Patients were included if they had signs and symptoms of active infection, including bacteremia of unknown origin, intra-abdomina l infection, and skin and skin-structure infection, with no alternative ant ibiotic therapy available. The mean duration of treatment was 20 days (rang e, 4-40 days). The clinical response rate was 68.8% in the evaluable subset , and the overall response rate was 65.6%. The most common adverse events r elated to quinupristin/dalfopristin were arthralgias and myalgias. Related laboratory abnormalities were rare. In this severely ill patient population , quinupristin/dalfopristin was efficacious and demonstrated an acceptable safety profile in the treatment of VREF infection.