Interim results for a prospective, randomized, double-blind multicenter study comparing continuous diffusion of oxygen therapy to standard moist wound therapy in the treatment of diabetic foot ulcers

Diabetic foot ulcers (DFU) are common, complex, and often difficult to treat. We examined planned interim data of a prospective, randomized, double-blind multi-center study comparing the clinical efficacy of the TransCu O2® device to standard moist wound therapy (MWT). The therapy, known as continuous diffusion of oxygen (CDO), delivers pure oxygen to the wound at low flow rates, preserves patient mobility, showed significant benefits in animal studies and received FDA clearance in August 2009. We summarize here the results of a per protocol interim analysis of complete wound closure at 12 weeks in a double blind 2-arm clinical trial of 84 subjects randomized 1:1 to Active CDO versus Sham, conducted when 50% of the planned number of subjects completed 12 weeks of therapy (Active 21, Sham 21). We also report treatment comparisons with regard to days to wound closure, study period, and after excluding subjects who experienced fast closure or a small wound (<1.5 cm2) at screen. Complete wound closure at 12 weeks was not significantly associated with treatment per protocol [Active 11 (52.3%), Sham 8 (38.1%), RR 1.38 (95% CI 0.7, 2.7), p = 0.54]. Wound size at Enrollment did not vary significantly with treatment (p = 0.3), days to closure was significantly less among patients who experienced closure in the Active (N = 9) arm relative to those in the Sham arm (N = 3) [mean difference 20 ± 7.9, 95% CI 2.4–37.5, p = 0.03], and complete wound closure at 12 weeks was significantly increased in the Active arm (N = 9) relative to Sham (N = 8) in the second half of the study [Active 77.8%, Sham 12.5%, p = 0.02]. With the numbers available to study in this interim analysis, the absolute performance in the Active arm appeared non-inferior to other reimbursable wound treatment devices.