Pain reduction and tolerability of mirogabalin in trigeminal neuralgia: A prospective observational study

OBJECTIVES/BACKGROUND: Our objective was to assess the short-term treatment response and tolerability of mirogabalin in patients with trigeminal neuralgia. Trigeminal neuralgia is a debilitating neuropathic pain disorder for which carbamazepine is the first-line therapy; however, this treatment is often limited by adverse effects. Mirogabalin, the third and most recently developed gabapentinoid, has demonstrated analgesic benefit with an acceptable safety profile in peripheral neuropathic pain conditions; however, its clinical role in trigeminal neuralgia remains unclear. METHODS: We conducted a prospective, open-label, single-arm observational pilot study at a single tertiary referral center in Japan between July 2021 and May 2025, enrolling 21 patients with trigeminal neuralgia, with pre- and postassessment of pain outcomes over a 3-month follow-up period. Pain intensity was assessed using the Numerical Rating Scale at baseline and at 1 and 3 months after treatment initiation. Responder rates and adverse events were also evaluated. RESULTS: The median Numerical Rating Scale score decreased from 6 (interquartile range [IQR], 6-8) at baseline to 2 (IQR, 2-4) at 1 month and 1 (IQR, 0-2) at 3 months (Friedman test, p < 0.001). At 1 month, 20 out of 21 patients (95%) achieved a ≥2-point reduction, and all evaluable patients (20 out of 20) met this threshold at 3 months. Response rates for ≥70% improvement increased from 6 out of 21 (29%) at 1 month to 14 out of 20 (70%) at 3 months (McNemar test, p = 0.008). No patients discontinued treatment because of adverse events. CONCLUSION: In this prospective, single-arm pilot study, mirogabalin was associated with short-term reductions in pain intensity and appeared to be generally well tolerated in patients with trigeminal neuralgia. These findings are hypothesis-generating and require confirmation in larger, controlled, and longer-term randomized trials to test the efficacy and safety of mirogabalin.