FOCUS 1: a randomized, double-blinded, multicentre, Phase III trial of the efficacy and safety of ceftaroline fosamil versus ceftriaxone in community-acquired pneumonia

Objectives: Ceftaroline, the active form of the prodrug ceftaroline fosamil, is a novel cephalosporin with bactericidal activity against important pathogens associated with community-acquired pneumonia (CAP), including Streptococcus pneumoniae and common Gram-negative pathogens. FOCUS 1 is a randomized, double-blinded, Phase III study that was conducted to evaluate the efficacy and safety of ceftaroline fosamil in treating patients with CAP. The primary objective was to determine non-inferiority [lower limit of 95% confidence interval (CI) ≥ 210%] in clinical cure rates achieved with ceftaroline fosamil compared with those achieved with ceftriaxone in the clinically evaluable (CE) and modified intent-to-treat efficacy (MITTE) populations. Methods: Patients hospitalized in a non-intensive care unit setting with CAP of Pneumonia Outcomes Research Team (PORT) risk class III or IV requiring intravenous (iv) therapy were randomized (1:1) to receive 600 mg of ceftaroline fosamil iv every 12 h or 1 g of ceftriaxone iv every 24 h. Patients also received two 500 mg doses of oral clarithromycin every 12 h administered on day 1. Clinical cure, microbiological response, adverse events (AEs) and laboratory tests were assessed. FOCUS 1 registration number NCT00621504 (http://clinicaltrials.gov/ ct2/show/NCT00621504). Results: Of 613 enrolled patients, 298 received ceftaroline fosamil and 308 received ceftriaxone. Baseline characteristics between treatment groups were comparable. Clinical cure rates were as follows: CE population, 86.6% (194/224) for ceftaroline fosamil and 78.2% (183/234) for ceftriaxone [difference (95% CI), 8.4% (1.4, 15.4)]; and MITTE population, 83.8% (244/291) for ceftaroline fosamil and 77.7% (233/300) for ceftriaxone [difference (95% CI), 6.2% (20.2, 12.6)]. Clinical cure rates for CAP caused by S. pneumoniae in the microbiological MITTE population were 88.9% (24/27) and 66.7% (20/30) for ceftaroline fosamil and ceftriaxone, respectively. Both agents were well tolerated, with similar rates of AEs, serious AEs, deaths and discontinuations because of an AE. The most common AEs for ceftaroline fosamil-treated patients were diarrhoea, headache, insomnia and nausea, and the most common AEs for ceftriaxone-treated patients were hypokalaemia, hypertension, nausea and diarrhoea. Conclusions: Ceftaroline fosamil demonstrated high clinical cure and microbiological response rates in hospitalized patients with CAP of PORTrisk class III or IV. Ceftaroline fosamil was well tolerated, with a safety profile similar to that of ceftriaxone and consistent with the cephalosporin class. In this study, ceftaroline fosamil was an effective and well-tolerated treatment option for CAP

Phase 2 Study of Ceftaroline versus Standard Therapy in Treatment of Complicated Skin and Skin Structure Infections▿

Ceftaroline, the bioactive metabolite of ceftaroline fosamil (previously PPI-0903, TAK-599), is a broad-spectrum cephalosporin with potent in vitro activity against multidrug-resistant gram-positive aerobic pathogens, including methicillin-resistant Staphylococcus aureus. A randomized, observer-blinded study to evaluate the safety and efficacy of ceftaroline versus standard therapy in treating complicated skin and skin structure infections (cSSSI) was performed. Adults with cSSSI, including at least one systemic marker of inflammation, were randomized (2:1) to receive intravenous (i.v.) ceftaroline (600 mg every 12 h) or i.v. vancomycin (1 g every 12 h) with or without adjunctive i.v. aztreonam (1 g every 8 h) for 7 to 14 days. The primary outcome measure was the clinical cure rate at a test-of-cure (TOC) visit 8 to 14 days after treatment. Secondary outcomes included the microbiological success rate (eradication or presumed eradication) at TOC and the clinical relapse rate 21 to 28 days following treatment. Of 100 subjects enrolled, 88 were clinically evaluable; the clinical cure rate was 96.7% (59/61) for ceftaroline versus 88.9% (24/27) for standard therapy. Among the microbiologically evaluable subjects (i.e., clinically evaluable and having had at least one susceptible pathogen isolated at baseline), the microbiological success rate was 95.2% (40/42) for ceftaroline versus 85.7% (18/21) for standard therapy. Relapse occurred in one subject in each group (ceftaroline, 1.8%; standard therapy, 4.3%). Ceftaroline exhibited a very favorable safety and tolerability profile, consistent with that of marketed cephalosporins. Most adverse events from ceftaroline were mild and not related to treatment. Ceftaroline holds promise as a new therapy for treatment of cSSSI and other serious polymicrobial infections

Pharmacodynamics of β-Lactamase Inhibition by NXL104 in Combination with Ceftaroline: Examining Organisms with Multiple Types of β-Lactamases

New broad-spectrum β-lactamases such as KPC enzymes and CTX-M-15 enzymes threaten to markedly reduce the utility of our armamentarium of β-lactam agents, even our most potent drugs, such as carbapenems. NXL104 is a broad-spectrum non-β-lactam β-lactamase inhibitor. In this evaluation, we examined organisms carrying defined β-lactamases and identified doses and schedules of NXL104 in combination with the new cephalosporin ceftaroline, which would maintain good bacterial cell kill and suppress resistance emergence for a clinically relevant period of 10 days in our hollow-fiber infection model. We examined three strains of Klebsiella pneumoniae and one isolate of Enterobacter cloacae. K. pneumoniae 27-908M carried KPC-2, SHV-27, and TEM-1 β-lactamases. Its isogenic mutant, K. pneumoniae 4207J, was “cured” of the plasmid expressing the KPC-2 enzyme. K. pneumoniae 24-1318A carried a CTX-M-15 enzyme, and E. cloacae 2-77C expressed a stably derepressed AmpC chromosomal β-lactamase. Dose-ranging experiments for NXL104 administered as a continuous infusion with ceftaroline at 600 mg every 8 h allowed identification of a 24-h area under the concentration-time curve (AUC) for NXL104 that mediated bactericidal activity and resistance suppression. Dose fractionation experiments identified that “time > threshold” was the pharmacodynamic index linked to cell kill and resistance suppression. Given these results, we conclude that NXL104 combined with ceftaroline on an 8-hourly administration schedule would be optimal for circumstances in which highly resistant pathogens are likely to be encountered. This combination dosing regimen should allow for optimal bacterial cell kill (highest likelihood of successful clinical outcome) and the suppression of resistance emergence