Safety and Efficacy Study of BC-DN-01 in Painful Diabetic Peripheral Neuropathy

A combined Phase 1 \& 2 study to evaluate the safety and effectiveness of a new diabetic neuropathy topical cream, containing benfotiamine, will be performed at 5 clinical sites and plans for BC-DN-01 administration in up to 135 volunteer patients using a standard Phase 1 + 2 design. Up to 15 subjects will receive BC-DN-01 in Study Phase 1 and up to 120 subjects will receive BC-DN-01 or placebo in Study Phase 2. In Phase 1, a BC-DN-01 dose delivering 160mg benfotiamine/day (80mg twice daily) will be administered for the first 7 days. On visit day 0, patients will commence study treatment. Patients will be interviewed by phone on day 3 and return to clinic on day 7 for safety assessments. If the drug is well-tolerated and no significant adverse events experienced, the total daily BC-DN-01 dose will be increased on days 7-14 to 320mg benfotiamine/day (160mg b.i.d.). Patients will be interviewed by telephone on day 10 and return to clinic on day 14 for safety assessments. Once the safety profile has been determined in Phase 1 as acceptable, the Phase 2 study will be initiated to evaluate clinical efficacy of BC-DN-01. Phase 2 is a randomized, placebo-controlled, double-blind, parallel study. Participants receive placebo or BC-DN-01 based on 1:1 randomization. Each patient will apply 4g of the study medication to each leg twice-a-day administering 320mg benfotiamine dose/day for 12 weeks. Participants will be evaluated in the clinic at baseline and at 4, 8, and 12-week time points; study staff will interview the patients by telephone on weeks 2, 6, and 10. The primary endpoint of the phase 2 trial is reduction in DPN pain measured by the Brief Pain Inventory. Phase 2 patients will be invited to give written consent to take part in biopsy sampling and additional gene expression analysis.