The safety and efficacy of pregabalin for treating subjects with fibromyalgia and moderate or severe baseline widespread pain

Abstract

Objective To evaluate pregabalin’s efficacy (≤12 weeks) for pain relief and sleep improvement in patients with fibromyalgia (FM) and moderate-to-severe baseline pain.Research design and methods Data were pooled from five randomized, double-blind, placebo-controlled, phase III clinical trials of pregabalin (300–450 mg/day) for FM treatment. Subjects, aged ≥18 years, had moderate (≥4–<7) or severe (≥7–10) mean baseline pain scores. Analyses included mixed effects repeated measures (MMRM), baseline observation carried forward (for parameters without enough data points for MMRM), or logistic regression.Clinical trial registration Study number/ClinicalTrials.gov number: A0081056/NCT00645398, A0081077/NCT00230776, A0081100/NCT00333866, A0081208/NCT00830167.Main outcomes measures Endpoints included mean change in pain and sleep quality scores (Weeks 8 and 12), patient-reported outcomes, and adverse events (AEs).Results Baseline demographic characteristics were comparable between pregabalin and placebo in both baseline pain severity groups. Mean ± SD baseline pain severity scores were equivalent between pregabalin and placebo within moderate (5.8 ± 0.8) or severe pain (7.9 ± 0.7) subgroups. All subjects reported reduced pain and improved sleep quality through Weeks 8 and 12, with larger effects observed with pregabalin over placebo and with baseline severe over moderate pain (all p < 0.01). Pregabalin was generally well tolerated, AE findings were consistent with previously published trials, and AE profiles were similar between moderate and severe baseline pain subgroups. Limitations of this pooled analysis included differences in individual trial designs (e.g., dosing schedules, racial distribution, exclusion criteria that did not enroll mild severity patients).Conclusions Pregabalin was efficacious through 12 weeks for reducing pain and improving sleep quality in FM patients with baseline moderate or severe pain, with larger effects in the baseline severe pain subgroup. AEs were consistent with pregabalin’s known safety profile and did not differ between moderate and severe pain subgroups.