Efficacy of a new pharmacokinetically enhanced formulation of amoxicillin/clavulanate (2000/125 mg) in adults with community-acquired pneumonia caused by Streptococcus pneumoniae, including penicillin-resistant strains

Community-acquired pneumonia (CAP) is a common respiratory illness, frequently caused by Streptococcus pneumoniae. The prevalence of S. pneumoniae resistance to common antimicrobials has increased over recent years. A new pharmacokinetically enhanced formulation of amoxicillin/clavulanate (2000/125mg) has been developed, designed to combat infections caused by S. pneumoniae, including penicillin-resistant (PRSP, penicillin minimum inhibitory concentrations (MICs) ≥2mg/l) isolates, and those with elevated amoxicillin/clavulanic acid MICs, while maintaining coverage of β-lactamase-producing pathogens. A pooled efficacy analysis of four randomized (1:1) and one non-comparative clinical trials of amoxicillin/clavulanate, 2000/125mg, given twice daily, was conducted in adult patients with CAP. Comparator agents were conventional amoxicillin/clavulanate formulations. At follow-up (days 16–39), efficacy (eradication of the initial pathogen or clinical cure in patients for whom no repeat culture was performed) in patients with S. pneumoniae infection was 92.3% (274/297) for amoxicillin/clavulanate, 2000/125mg and 85.2% (46/54) for comparators (P=0.11). Twenty-four of 25 PRSP-infected patients receiving amoxicillin/clavulanate, 2000/125mg were treated successfully. Both amoxicillin/clavulanate, 2000/125mg and comparators were well tolerated, with few patients withdrawing from the studies.