L-683. A Comparative Study of the Safety and Efficacy of Cethromycin (CER) to Clarithromycin (CLR) for the Treatment of Community Acquired Pneumonia (CAP) in Adults (CL05-001)
Session: Poster Session: The World of Community-Acquired Pneumonia
Saturday, October 25, 2008: 12:00 AM
Room: Hall C
Background: CAP is a major cause of death globally and is the sixth most common cause of death in the US. CER is a new ketolide having a potent antibacterial spectrum with activity against penicillin- and macrolide-resistant Gram-positive bacteria. Methods: A phase III, double-blind, randomized, parallel group, multi-center study, conducted in the US, Canada, and South Africa, compared the safety and efficacy of CER 300 mg QD to CLR (BIAXIN® Filmtab®) 250 mg BID, for 7 days. Subjects were ambulatory adults with mild-to-moderate CAP, as evidenced by appropriate signs and symptoms, and by a positive chest x-ray as interpreted by a radiologist. The primary end point was clinical response at the test-of-cure (TOC) visit (days 14 to 22) in the intent-to-treat (ITT) and per protocol (PP) populations.
Results: A total of 584 subjects were randomized, and 582 were treated.
Clinical Cure (%)Radiographic Cure (%)
CERCLRCI CERCLR CI
ITT83.181.1[-4.8%, +8.9%] (p=0.5667)82.481.5[-6.0%, +7.7%] (p=0.8195)
PP94.093.8[-4.5%, +5.1%] (p>0.9999)92.792.3[-4.9%, +5.6%] (p>0.9999)

In the PP population, 142 subjects were identified with a pre-treatment pathogen; the most common were H. influenzae, M. pneumoniae, S. pneumoniae, and S. aureus. The bacteriological cure rates in this population were 97.3% and 97.1% % for CER and CLR, respectively. The incidence of treatment emergent adverse events was 38.9% and 38.8% for CER and CLR, respectively. The most commonly reported adverse events were dysgeusia (7.6%), diarrhea (4.5%), and nausea (4.5%) for CER. Conclusions: CER achieved non-inferiority of clinical response in CAP compared to CLR. CER demonstrated safety results that were similar to those observed with CLR and were consistent with the favorable safety profile seen with CER in previous clinical trials.
Christine Fredericks1, David Eiznhamer, PhD2, Marci English1, Michael Flavin, PhD2, Nancy Milanesio1, Nestor Rohowsky1, Z Xu1 and  D. A. Eiznhamer,
Advanced Life Sciences Role(s): Employee, Shareholder (excluding diversified mutual funds), Received: Salary., (1)Advanced Life Sciences, (2)Advanced Life Sciences, Woodridge, IL