A genetic variation of the µ-opioid receptor did not predict response to naltrexone for the treatment of alcohol dependence, found a randomized trial including 221 alcohol-dependent people who were stratified by genotype. Based on previous preclinical research and encouraging clinical trial data, the researchers had hypothesized that the single-nucleotide polymorphism of the µ-opioid receptor gene (A+118G, Asn40Asp) would moderate response to naltrexone treatment (Oslin DW et al. JAMA Psychiatry. doi:10.1001/jamapsychiatry.2014.3053 [published online March 11, 2015]). Participants were randomly assigned to receive once-daily naltrexone treatment or placebo based on the presence of 1 or 2 copies of the Asp40 allele compared with those homozygous for the Asn40 allele in the 12-week trial. The researchers found that genotype had no effect on whether participants relapsed to heavy drinking after naltrexone treatment.
Slomski A. Genotype Doesn’t Affect Response to Naltrexone for Alcohol Dependence. JAMA. 2015;313(20):2015. doi:10.1001/jama.2015.5173