Safety and efficacy of omadacycline by BMI categories and diabetes history in two Phase III randomized studies of patients with acute bacterial skin and skin structure infections

Objectives: The objectives of this post-hoc analysis were to examine the safety and efficacy of omadacycline by BMI categories and diabetes history in adults with acute bacterial skin and skin structure infections (ABSSSI) from two pivotal Phase III studies.

Patients and methods: OASIS-1 (ClinicalTrials.gov identifier NCT02378480): patients were randomized 1:1 to IV omadacycline or linezolid for 7-14 days, with optional transition to oral medication. OASIS-2 (ClinicalTrials.gov identifier NCT02877927): patients received once-daily oral omadacycline or twice-daily oral linezolid for 7-14 days. Early clinical response (ECR) was defined as ≥20% reduction in lesion size 48-72 h after the first dose. Clinical success at post-treatment evaluation (PTE; 7-14 days after the last dose) was defined as symptom resolution such that antibacterial therapy was unnecessary. Safety was assessed by treatment-emergent adverse events and laboratory measures. Between-treatment comparisons were made with regard to WHO BMI categories and diabetes history.

Results: Patients were evenly distributed among healthy weight, overweight and obese groups. Clinical success for omadacycline-treated patients at ECR and PTE was similar across BMI categories. Outcomes by diabetes status were similar in omadacycline- and linezolid-treated patients: at ECR, clinical success rates were lower for those with diabetes; at PTE, clinical success was similar between treatment groups regardless of diabetes history. The safety of omadacycline and linezolid was largely similar across BMI groups and by diabetes history.

Conclusions: Omadacycline efficacy in patients with higher BMI and in patients with diabetes was consistent with results from two pivotal Phase III ABSSSI trials. Fixed-dose omadacycline is an appropriate treatment for ABSSSI in adults regardless of BMI.