Due to the modest effect of current pharmacotherapies, more effective treatments must be developed to optimally treat alcohol dependent patients. Treatments combining pharmacotherapies with different mechanisms of action may better address the diverse neurobiology of alcohol and the heterogeneity of alcoholics. However, little is known about how medication may affect behavior to reduce drinking. Aripiprazole (APZ), a partial dopamine agonist, affects dopamine and serotonin receptors without the limiting side effects seen with other atypical antipsychotics. Dopamine mediates reward based drinking and craving. Topiramate (TPMT), an antiepileptic, affects glutamate and GABA-A receptors and shows promise in reducing heavy drinking. Glutamate and GABA may mediate relief-based drinking and protracted withdrawal. Despite strong evidence that multiple neurotransmitters contribute to alcoholism, few studies have used two medications with such a diverse combination of actions to examine a potential synergistic effect on reducing alcohol consumption.~The present study will recruit 216 healthy, alcohol-dependent volunteers who are not currently seeking treatment for their alcohol dependence to learn more about how these medications may work.~The primary aims are to: (1) determine if APZ and TPMT are each more effective than placebo, and the combination of APZ and TPMT is more effective than either drug alone or placebo, in reducing alcohol use in non-treatment seeking alcohol dependent subjects in an alcohol self administration experiment (ASAE); (2) examine a hypothesized dose-response for three doses of APZ (0, 7.5mg/d and 15 mg/d) and three doses of TPMT (0, 100mg/d, 200mg/d); (3) examine the putative mechanisms of action of APZ, TPMT alone and together on craving, subjective stimulation, candidate gene influences and other behavioral effects associated with alcohol consumption; and (4) establish the safety of giving APZ and TPMT together. We will use of a 3 X 3 drug (7.5mg, 15mg APZ vs. placebo) by drug (100mg, 200mg TPMT vs. placebo) between-subjects factorial design. Participants are randomly assigned to one of 9 cells. Subjects drinking and safety is monitored over a 5-week titration to their target dose, leading to an in-laboratory alcohol self administration session, during which clinical and behavioral effects are assessed during access to alcohol. A 1 month follow-up assesses adverse events and drinking. The long term objectives of this research are to improve medications available for alcoholism treatment and inform research and theory on the mechanisms of action of such medications.
The current study investigates the effects of two potential alcohol treatment medications on drinking in a laboratory setting. Aripiprazole (APZ), effects dopamine and serotonin receptors with fewer limiting side effects seen with other atypical antipsychotics. Topiramate (TPMT), an antiepileptic, affects glutamate and GABA-A receptors and shows promise in reducing heavy drinking. Few studies have used two medications with such a diverse combination of actions to examine a potential synergistic effect on reducing alcohol consumption.~The primary aims are to:~determine if APZ and TPMT are each more effective than placebo, and the combination of APZ and TPMT is more effective than either drug alone or placebo, in reducing alcohol use in non-treatment seeking alcohol dependent subjects in a laboratory based alcohol self-administration experiment (ASAE)~examine a hypothesized dose-response for three doses of APZ (0, 7.5 mg/d and 15 mg/d) along with three doses of TPMT (0, 100mg/d and 200mg/d)~examine the putative mechanisms of action of APZ, TPMT alone and together on craving, subjective stimulation, candidate gene influences and other behavioral effects associated with alcohol consumption~establish the safety of giving APZ and TPMT together. Non-treatment seeking, alcohol dependent Participants (N=216) will be recruited from the community and randomly assigned to one of the 9 cells. Subjects drinking and safety is monitored over a 5-week titration to their target dose, leading to an in-laboratory alcohol self administration session, during which clinical and behavioral effects are assessed during access to alcohol. A 1 month follow-up assesses adverse events and drinking.