Behavioral economic analysis of topiramate pharmacotherapy for alcohol: a placebo-controlled investigation of effects on alcohol reinforcing value and delayed reward discounting

RATIONALE: Pharmacotherapies are an important clinical strategy for treating alcohol use disorder and an understanding of their functional mechanisms can inform optimal use. Behavioral economics provides a translational platform that may advance our understanding of the motivational impacts of pharmacotherapies. OBJECTIVES: This secondary analysis study examined the effect of topiramate, a promising pharmacotherapy for treating alcohol use disorder, on two behavioral economic domains, the reinforcing value of alcohol (alcohol demand and alcohol-specific monetary expenditures) and delayed reward discounting (preference for smaller immediate rewards over larger delayed rewards). METHODS: A double-blind randomized placebo-controlled study (n = 99) was conducted with non-treatment seeking heavy drinkers, comparing topiramate (target dose of 200 mg/day titrated for 3 weeks and remained at the target dose for 2 weeks) to matched placebo. RESULTS: We found that compared to placebo, topiramate reduced the reinforcing value of alcohol, as shown by a reduction in two alcohol demand indices (intensity and O(max)), money spent per week on alcohol and an almost a 50% increase in days without expenditures on alcohol from baseline. Directionally consistent patterns were also present for breakpoint and elasticity (ps = .08). No significant effects were found for delayed reward discounting. CONCLUSIONS: This study provides evidence that topiramate reduces alcohol’s reinforcing value as measured by alcohol demand and alcohol expenditure. More broadly, these findings support the utility of behavioral economics for understanding how medications reduce alcohol use.