Pregabalin (Lyrica Capsules CV; Pfizer) did not improve pain associated with fibromyalgia in adolescents aged 12 to 17 years, according to results of a phase 4 double-blind, placebo-controlled, Pfizer-sponsored, postmarketing study reported recently. Pregabalin capsules were not significantly better than placebo in improving mean pain score.
A news release from Pfizer states that this is the first large pharmacological treatment study to be completed in this population. The study results suggest that pregabalin capsules are not a good choice for this group of patients. Pfizer conducted the study to meet US Food and Drug Administration (FDA) requirements after pregabalin was approved for fibromyalgia. Pregabalin has been FDA approved for the treatment of fibromyalgia in adults since 2007, and it has been widely used for that condition. The drug is also approved for various indications in 139 countries and regions of the world. However, a review of anecdotal experiences on the internet from patients with fibromyalgia treated with pregabalin suggests that pain relief is not universal and some patients have uncomfortable side effects.
The phase 4 trial enrolled 107 adolescents with fibromyalgia drawn from multiple centers in the United States, Europe, and Asia. Patients were randomized to receive pregabalin capsules or placebo treatment for 15 weeks. Study medication was administered twice a day. Dosing of pregabalin was initiated at 75 mg/day and optimized over a 3-week period, adjusting for tolerability and response, to one of the following levels: 75 mg/day, 150 mg/day, or 300 mg/day, with the best effective dose maintained for the next 12 weeks.
The treatment effect of pregabalin capsules on the mean pain score was not significantly different from that of placebo. The difference of 0.66 points represents an improvement of 1.60 points from baseline for pregabalin compared with 0.94 points for placebo (P=.121). The safety of pregabalin capsules in the adolescent population was mainly consistent with the known profile of pregabalin in adults, with the exception of nausea, which occurred more frequently in the pregabalin-treated group. The most common drug-related adverse events with pregabalin capsules were dizziness, nausea, headache, increased weight, and fatigue. Other commonly reported adverse events include constipation, euphoric mood balance disorder, increased appetite, and thinking abnormally. Pfizer press release: www.pfizer.com/news/press-release/press-release-detail/pfizer_reports_top_line_results_from_a_phase_4_study_evaluating_lyrica_capsules_cv_as_a_treatment_for_adolescents_with_fibromyalgia.
Last modified: May 21, 2015