Efficacy and safety of pregabalin in elderly people with generalised anxiety disorder

Background Pregabalin is a novel compound that has been shown to have efficacy in the treatment of generalised anxiety disorder and is licensed for the treatment of the disorder in the European Union. Aims The current study was designed to evaluate the safety and efficacy of pregabalin, an alpha(2)delta-ligand, in the treatment of generalised anxiety disorder in people 65 years and older. Method This was a double-blind, randomised (2:1), placebo-controlled, 8-week trial of pregabalin, in flexible doses of 150-600 mg/day, in the treatment of DSM-IV generalised anxiety disorder with a baseline Hamilton Rating Scale for Anxiety (HRSA) total score >= 20. The primary outcome was end-point (week 8 or last visit, with last observation carried forward (LOCF)) change in HRSA total score. Results A total of 273 patients (women, 78%; mean age, 72 years (s.d.=6); mean baseline HRSA total Score, 26 (s.d.=4.6)) were randomised and received study treatment. On the primary intent-to-treat LOCF analysis, pregalbalin was associated with a 2-point greater reduction in HRSA total score than placebo (12.87 V. 10.7; P<0.05). In a post hoc repeated measures mixed-effect model analysis, pregabalin was associated with significantly greater improvement than placebo in the HRSA total score from week 2 (-9.8 (s.d.=0.6) v. -7.2 (s.d-=0.8),P=0.0052) through week 8 (-14.4 (s.d.=0.6) v. -11.6 (s.d.=0.8); P=0.0070). Significant improvement was observed in the pregabalin group on both the HRSA psychic and somatic anxiety factors. There was a significantly greater decrease from baseline in mean Hamilton Rating Scale for Depression (HRSD) score with pregabalin compared with placebo (-5.48 (s.d.=0.46) v. -4.02 (s.d.=0.59), P=0.041). Pregabalin was well-tolerated, with almost all adverse events in the mild-to-moderate range, and self-limiting (median duration of 4-16 days). Discontinuations due to adverse events were similar for pregabalin (10.7%) and placebo (9.4%). Conclusions Pregabalin, in doses of 150-600 mg/day, was a safe and effective treatment of generalised anxiety disorder in patients 65 years and older. The anxiolytic efficacy of pregabalin had an early onset (by 2 weeks) and significantly improved both psychic and somatic symptoms of anxiety. Declaration of interest This study was sponsored by Pfizer Inc. S.M. has served on advisory boards for Pfizer, has received fees as a consultant to Pfizer, and has been reimbursed for travel-related expenses incurred for scientific meetings. K.C., L.P., E.W. and F.B. are full-time employees of Pfizer.