A phase 4 randomized active-controlled clinical study to compare the efficacy and safety of sustained-release pregabalin with immediate-release pregabalin in type 2 diabetic patients with peripheral neuropathic pain

Aims: The objective of this study was to demonstrate that sustained-release (SR) pregabalin is non-inferior to immediate-release (IR) pregabalin in attenuating diabetic peripheral neuropathic (DPN) pain along with patient satisfaction and compliance. Methods: This was an 8-week, randomized, active-controlled, open-label, phase 4 study. Eligible subjects who had been on IR pregabalin for 4 weeks were randomized to 1:1 ratio to either continue with twice-daily IR pregabalin (75 mg), or to switch to once-daily SR pregabalin (150 mg). Primary efficacy endpoint was the change in visual analogue scale (VAS) scores after 8 weeks of treatment compared to baseline in both SR and IR pregabalin groups. Results: Among 130 randomized subjects, 125 patients were included in full analysis set. For the change in VAS pain score, the least squares (LS) mean were −17.95 (SR pregabalin) and −18.74 (IR pregabalin) and the LS mean difference between both groups was 0.79, with the upper limit of the 95 % confidence interval [−5.99, 7.58] below the pre-specified non-inferiority margin of 9.2 mm. Conclusions: This study demonstrates that the new once-daily SR pregabalin formulation is not different to the twice-daily IR pregabalin in alleviating DPN pain, indicating its potential as a promising treatment for DPN pain with a comparable safety profile. Trial registration: ClinicalTrials.gov, NCT05624853.