A randomized, active-controlled, parallel, open-label, multicenter, phase 4 study to compare the efficacy and safety of pregabalin sustained release tablet and pregabalin immediate release capsule in type II diabetic patients with peripheral neuropathic pain

Diabetic peripheral polyneuropathy is the most common chronic complication of type 2 diabetes. Neuropathic pain is challenging to manage, and various drugs are required to control it, decreasing treatment adherence. Pregabalin, a ligand that binds to alpha-2-delta subunits of the presynaptic calcium channel, has been approved by the Food and Drug Administration for the treatment of diabetic neuropathic pain. In this study, we will compare the efficacy, safety, treatment satisfaction, and compliance between pregabalin sustained-release (SR) tablets and pregabalin immediate-release (IR) capsules in type 2 diabetic patients with peripheral neuropathic pain. METHODS: This study is a randomized, active-controlled, parallel, open-label, multicenter, phase 4 clinical trial (trial registration NCT05624853). Type 2 diabetic patients with glycosylated hemoglobin below 10% and peripheral neuropathic pain who have been taking pregabalin 150 mg/d or more for more than 4 weeks will be randomly assigned to pregabalin SR tablet (150 mg once a day, n = 65) or pregabalin IR capsule (75 mg twice a day, n = 65) therapy for 8 weeks. The primary outcome will be the efficacy of SR pregabalin after 8 weeks of treatment, which will be assessed by visual analog scale measurements. The secondary outcomes will include changes in several parameters, such as quality of life, treatment satisfaction, quality of sleep, and drug compliance. DISCUSSION: In thus study, we aim to demonstrate that pregabalin SR tablets are associated with better compliance and satisfaction compared with pregabalin IR capsules, despite similar efficacy.