A Pooled Analysis of the Safety and Efficacy of Iclaprim Versus Vancomycin for the Treatment of Acute Bacterial Skin and Skin Structure Infections in Patients With Intravenous Drug Use: Phase 3 REVIVE Studies.

Purpose: This analysis evaluates the efficacy and safety of iclaprim versus vancomycin for the treatment of acute bacterial skin and skin structure infections (ABSSSIs) in patients who were intravenous drug users (IVDUs).

Methods: A total of 621 patients who were IVDUs from 2 parallel Phase III, double-blind, randomized (1:1), active-controlled, multinational, multicenter trials (REVIVE-1 and REVIVE-2) were analyzed separately and pooled. This post hoc analysis summarizes the efficacy and safety profile of iclaprim 80 mg fixed dose compared with vancomycin 15 mg/kg administered intravenously during 2 h every 12 h for 5-14 days among this population. The primary end point of these studies was to determine whether iclaprim was noninferior (10% margin) to vancomycin in achieving a ≥20% reduction in lesion size at 48-72 h after initiation of treatment with the study drug (early clinical response) in the intent-to-treat population. The safety profile was assessed based on adverse events and laboratory parameters.

Findings: Iclaprim had higher early clinical response rates (85.8%; 95% CI, 81.5%-89.4%) compared with vancomycin (79.8%; 95% CI, 74.8%-84.2%) among patients with ABSSSIs who were IVDUs, with a treatment difference of +6.00% (95% CI, 0.06-12.0). The safety profile was similar in the iclaprim and vancomycin arms, with 3.7% and 5.0%, respectively, of patients discontinuing study therapy because of adverse events and 1.9% and 3.4%, respectively, of patients developing serious adverse events.

Implications: Iclaprim had a higher early clinical response rate and favorable safety profile compared with vancomycin for the treatment of ABSSSIs in patients who were IVDUs. Iclaprim may be a valuable treatment option for ABSSSIs in this patient population.