Phase 3 study comparing tigecycline and ertapenem in patients with diabetic foot infections with and without osteomyelitis

A phase 3, randomized, double-blind trial was conducted in subjects with diabetic foot infections without osteomyelitis (primary study) or with osteomyelitis (substudy) to determine the efficacy and safety of parenteral (intravenous iv) tigecycline (150 mg once-daily) versus 1 g once-daily iv ertapenem ± vancomycin. Among 944 subjects in the primary study who received ≥1 dose of study drug, >85% had type 2 diabetes; ~90% had Perfusion, Extent, Depth/tissue loss, Infection, and Sensation infection grade 2 or 3; and ~20% reported prior antibiotic failure. For the clinically evaluable population at test-of-cure, 77.5% of tigecycline- and 82.5% of ertapenem ± vancomycin-treated subjects were cured. Corresponding rates for the clinical modified intent-to-treat population were 71.4% and 77.9%, respectively. Clinical cure rates in the substudy were low (<36%) for a subset of tigecycline-treated subjects with osteomyelitis. Nausea and vomiting occurred significantly more often after tigecycline treatment (P = 0.003 and P < 0.001, respectively), resulting in significantly higher discontinuation rates in the primary study (nausea P = 0.007, vomiting P < 0.001). In the primary study, tigecycline did not meet criteria for noninferiority compared with ertapenem ± vancomycin in the treatment of subjects with diabetic foot infections.