Early improvement with pregabalin predicts endpoint response in patients with generalized anxiety disorder: an integrated and predictive data analysis

Effect of valproate and pregabalin on human anxiety-like behaviour in a randomised controlled trial

Valproate is an anticonvulsant drug with strong preclinical evidence for reducing anxiety behaviour in rodents but no clear clinical evidence. To motivate clinical trials, we here investigate the use of valproate in a translational human model of anxiety behaviour. In a double-blind, randomised, placebo-controlled trial, n = 118 healthy participants played a previously validated approach/avoidance conflict computer game to measure anxiety-like behaviour, while under 400 mg valproate, under 200 mg of the established anxiolytic/anticonvulsant pregabalin, or under placebo. Saccadic peak velocity and subjective ratings were assessed to control for drug-induced sedation. Compared to placebo, valproate and pregabaline were anxiolytic in the primary outcome, and several secondary outcomes. Bayesian model comparison decisively demonstrated no differences between the two drugs. Subjective and objective sedation was significantly more pronounced under pregabalin than valproate, but did not explain anxiolytic effects. We demonstrate acute anxiolytic properties of valproate in healthy humans. Both drugs have similar anxiolytic properties at the doses used. Valproate is less sedative than pregabalin. Our results suggest clinical trials on the use of valproate in anxiolytic treatment. More generally, we propose a strategy of screening drugs in human preclinical models that can directly be compared across species, such as the approach/avoidance conflict computer game used here. This approach could thus facilitate translational anxiety research.

[Anxiety associated with substance abuse]

Substance abuse and anxiety is a common comorbid dyad and an example of so-called dual diagnosis in psychiatry. Comorbidity of anxiety and addictive disorders may be due to interdependence of these states as well as common predisposing factors and pathogenic mechanisms. There are various medicines in the treatment of anxiety associated with substance abuse, including benzodiazepines, calcium channel modulators, non-benzodiazepine anxiolytics, antidepressants and antipsychotics. One of the best approaches to the treatment of chronic anxiety disorders in drug treatment clinic is a long course of treatment with antidepressants, primarily with selective serotonin reuptake inhibitors as first line preparations. Such medications as pregabalin, buspirone, etifoxine and alimemazine are also of interest for the treatment of dual diagnosis patients.