A randomized double-blind, placebo-controlled trial of venlafaxine-extended release for co-occurring cannabis dependence and depressive disorders

Aim To evaluate whether venlafaxine‐extended release (VEN‐XR) is an effective treatment for cannabis dependence with concurrent depressive disorders. Design This was a randomized, 12‐week, double‐blind, placebo‐controlled trial of out‐patients (n = 103) with DSM‐IV cannabis dependence and major depressive disorder or dysthymia. Participants received up to 375 mg VEN‐XR on a fixed‐flexible schedule or placebo. All patients received weekly individual cognitive–behavioral psychotherapy that primarily targeted marijuana use. Settings The trial was conducted at two university research centers in the United States. Participants One hundred and three cannabis‐dependent adults participated in the trial. Measurements The primary outcome measures were (i) abstinence from marijuana defined as at least two consecutive urine‐confirmed abstinent weeks and (ii) improvement in depressive symptoms based on the Hamilton Depression Rating Scale. Findings The proportion of patients achieving a clinically significant mood improvement (50% decrease in Hamilton Depression score from baseline) was high and did not differ between groups receiving VEN‐XR (63%) and placebo (69%) (χ12 = 0.48, P = 0.49). The proportion of patients achieving abstinence was low overall, but was significantly worse on VEN‐XR (11.8%) compared to placebo (36.5%) (χ12 = 7.46, P