Twice daily versus once nightly dosing of pregabalin for fibromyalgia: a double-blind randomized clinical trial of efficacy and safety

Abstract

Objective: To compare the efficacy, discontinuation rates, and safety of once nightly versus twice daily dosing of pregabalin in a community-based trial.

Methods: This multicenter, double-blind, 8-week randomized clinical trial compared the effects of 300-mg daily doses of pregabalin given either twice daily or once nightly for the treatment of fibromyalgia in 177 patients. The primary outcome was the comparison of end point mean pain scores derived from a daily diary.

Results: Both twice daily (88 patients randomized) and once nightly (89 patients) pregabalin significantly reduced the average severity of pain experienced by patients (P < 0.001 for both). Treatment-emergent adverse events were reported by significantly more patients in the twice daily group than those in the once nightly group (P = 0.023). There were no significant differences between the groups for the frequencies of individual adverse events (P > 0.05 for all). There was no significant difference in adverse events or efficacy in patients taking both pregabalin and a selective serotonin and norepinephrine reuptake inhibitor or selective serotonin uptake inhibitor.

Conclusion: While a nightly dosing schedule of pregabalin has been used by clinicians hoping to improve treatment, this study showed no significant difference (either beneficial or detrimental) between either treatment option. While there was a decrease in total patient-reported adverse events in the once nightly arm, the lack of specificity in relation to a particular adverse event suggested no real difference in adverse events.

Trial registration: ClinicalTrials.gov NCT01226667.