Aripiprazole lauroxil (AL), a new long-acting injectable antipsychotic, demonstrated safety and efficacy in treating acute exacerbation symptoms of schizophrenia in a 12-week placebo-controlled trial of two doses of AL (441mg and 882mg) administered every 4weeks. We performed a post hoc analysis of this trial to evaluate the efficacy of AL in the subgroup of patients with severe psychotic symptoms, defined as those with baseline Positive and Negative Syndrome Scale (PANSS) Total score above the median score of 92 (n=309). Change from baseline to Day 85 in PANSS Total score; Positive, Negative, and General Psychopathology subscale scores; and overall response rate were assessed. Statistically significant and clinically meaningful improvements in PANSS Total score were demonstrated with AL 441mg and AL 882mg, with placebo-adjusted differences of -14.7 (p<0.0001) and -16.6 (p<0.0001), respectively. Significant and clinically meaningful findings with both doses of AL were also demonstrated for the PANSS subscales and responder rates. Overall responder rates at Day 85 were significantly greater for AL 441mg (49%; p<0.001) and 882 mg (61%; p<0.001) groups vs. placebo (18%). Common adverse events (>5%) were schizophrenia, akathisia, headache, insomnia, and anxiety. AL demonstrated robust efficacy in treatment of the subgroup of patients experiencing severe psychotic symptoms. Both doses (441mg and 882mg) were effective, with numerically greater improvement in symptoms and proportion of responders favoring the higher dose arm. Both doses had a side effect profile consistent with the known safety profile of aripiprazole.

Objectives

Once-monthly intramuscular extended-release naltrexone (XR-NTX) has demonstrated efficacy for the prevention of relapse in opioid dependence, providing an alternative to agonist or partial agonist maintenance (ie, methadone and buprenorphine). The question remains, for whom is this unique treatment most efficacious and can patient-treatment matching factors be identified?

Methods

A moderator analysis was conducted on a previously reported 24-week, placebo-controlled, multisite, randomized controlled trial of XR-NTX (n = 126) versus placebo (n = 124) among recently detoxified opioid-dependent adults in Russia, which showed XR-NTX superior to placebo in proportion of opioid abstinent weeks. The moderator analysis examined a dichotomous indicator of good clinical response-achieving at least 90% of weeks abstinent over the 24-week trial. A series of logistic regression models were fit for this outcome as functions of treatment (XR-NTX vs placebo), each baseline moderator variable, and their interactions. The 25 baseline variables included demographics, clinical severity (Addiction Severity Index, SF-36, and Clinical Global Impression-Severity), functioning (EQ-5D), craving, and HIV serostatus (HIV+).

Results

More XR-NTX patients achieved 90% abstinence (64/126, 51%) versus placebo (39/124, 31%; P = 0.002). There were no significant interactions between baseline variables and treatment. There was a significant main effect of Clinical Global Impression-Severity score (P = 0.02), such that higher severity score was associated with a lower rate of Good Clinical Response.

Conclusions

The absence of significant baseline by treatment interactions indicates that no patient-treatment matching variables could be identified. This suggests that XR-NTX was effective in promoting abstinence from opioids across a range of demographic and severity characteristics.