There was no significant difference between the groups in terms of the number of days of cumulative abstinence in the 24-week treatment period (73.86 ± 36.22% for the acamprosate group compared with 74.16 ± 33.31% for the placebo group; P = .310; Wilcoxon rank sum test). Kaplan-Meier survival analysis of the time elapsed between study drug initiation and the third day of 3 or more consecutive days of heavy drinking showed that nonrelapse rates at the end of the administration period were broadly similar (58.9% for the acamprosate group compared with 57.3% for the placebo group; P = .961; log-rank test).