Efficacy of the Novel Formulation of Topical Liothyronine and Liothyronine-Insulin in Mild to Moderate Diabetic Foot Ulcer: A Randomized, Triple-blind Clinical Trial

Background: Diabetic foot ulcer (DFU) is one of the challenging complications of chronic diabetes. Objective: The study aimed to investigate whether liothyronine (T3) and liothyronineinsulin (T3/Ins) topical preparations could significantly reduce the healing time of DFU. Methods: A prospective, randomized, placebo-controlled, patient-blinded clinical trial was conducted on patients with mild to moderate DFU, over a lesion area of no greater than 100 cm2. The patients were randomized to receive T3, T3/Ins, or honey cream 10% as the routine of care twice a day. Patients were examined for tissue healing weekly for 4 weeks, or until the total lesion clearance was observed, whichever was earlier. Results: Of 147 patients with DFUs, 78 patients (26 per group) completed the study and were included in the final evaluation. At the time of study termination, all participants in each of the T3 or T3/Ins groups were free of symptoms based on the REEDA score, while about 40% of participants in the control group were detected with each of grades 1, 2, or 3. A significant difference was observed on days 7, 14, and 21 of consumption of topical preparations (p-value < 0.001). The mean time to complete wound closure in the routine care group was about 60.6 days, while it was 15.9 and 16.4 days in T3 and T3/Ins groups, respectively. Within the T3 and T3/Ins groups, significant earlier wound closure was detected at day 28 (p-value < 0.001). Conclusion: T3 or T3/Ins topical preparations are effective for wound healing and acceleration of wound closure in mild to moderate DFUs. Trial Registration: Iranian Registry of Clinical Trials Identifier: IRCT201908100 44500N20, https://www.irct.ir/trial/ 46886, Registration date: 2021-08-22