Abstract
BACKGROUND: Chemotherapy-induced peripheral neuropathy (CIPN) is a painful, dose-limiting adverse effect of commonly used chemotherapeutic agents. The purpose of this exploratory study was to evaluate the efficacy and safety of mirogabalin in patients with moderate to severe CIPN during chemotherapy and the effects of 12 weeks' intervention on chemotherapy completion and CIPN severity. METHODS: Patients experiencing moderate to severe CIPN while undergoing oxaliplatin- or taxane-containing chemotherapy for colorectal, gastric, non-small-cell lung, or breast cancer received mirogabalin at between 5 and 15 mg twice daily. The primary endpoint was change in numeric rating scale (NRS) score for pain from baseline to week 12. Secondary endpoints included NRS scores for tingling and sleep, completion of chemotherapy, severity of CIPN, and quality of life (QOL) scores. The safety endpoint was incidence of adverse events. RESULTS: Of 58 patients who consented to participation, 52 were eligible and constituted the full analysis set and safety analysis set. From baseline to week 12 (last observation carried forward [LOCF]), NRS score decreased by 30.9%: mean change (95% confidence interval [CI]), - 1.7 (- 2.4 to - 1.0) (p < 0.001). Patients with baseline NRS of ≥ 6 experienced a 44.0% reduction in score from baseline to week 12 (LOCF): mean change (95% CI), - 3.3 (- 5.0 to - 1.5) (p = 0.002). Chemotherapy was discontinued in 18 (34.6%) patients; CIPN led to discontinuation in only 2 (3.8%). There was no notable worsening of CIPN severity in terms of Common Terminology Criteria for Adverse Events grade or Modified Total Neuropathy Score-reduced, although use of pain medications during chemotherapy might cause worsening of CIPN due to underestimation of subjective symptoms. QOL score based on the EuroQol five-dimensional descriptive system did not worsen during the 12 weeks. Thirty-one percent of patients experienced adverse drug reactions, and the most common event was somnolence (13.5%). Serious adverse events and death occurred in 3 patients and 1 patient, respectively; however, they were unrelated to mirogabalin treatment. CONCLUSIONS: Intervention with mirogabalin during chemotherapy may be effective and safe for cancer patients with moderate to severe CIPN. It can contribute to completion of chemotherapy without worsening of CIPN. TRIAL REGISTRATION: Japan Registry of Clinical Trials (jRCTs031210101, registered 20/5/2021).