Reduced sexual dysfunction with aripiprazole once-monthly versus paliperidone palmitate: results from QUALIFY, a head-to-head study in schizophrenia

Objective: The QUALIFY study directly compared treatment effectiveness of the dopamine D2 receptor partial agonist aripiprazole once-monthly 400 mg (AOM 400) against the D2 antagonist paliperidone palmitate once-monthly (PP) in patients with schizophrenia. Post-hoc analyses assessed incidence of sexual dysfunction. Methods: QUALIFY was a 28-week, randomized, open-label, head-to-head study (NCT01795547) of AOM 400 and PP (50-150 mg/month as paliperidone [EU and Canada], 78-234 mg/month as paliperidone palmitate [US]). The Arizona Sexual Experience Scale (ASEX) is a patient-rated scale used to identify sexual dysfunction. Odds ratios (OR) for sexual dysfunction after AOM 400 and PP treatment were calculated with logistic regression adjusted for baseline presence/absence of sexual dysfunction. Serum prolactin concentrations were summarized with descriptive statistics. Results: Primary analysis showed superior improvements with AOM 400 vs PP on Heinrichs-Carpenter Quality-of-Life Scale (QLS, p=0.036). Patients had lower odds for sexual dysfunction after 28 weeks of AOM 400 vs PP treatment (adjusted OR: 0.29, 95%CI:[0.14;0.61], p=0.001), and this was significant in males (adjusted OR: 0.33, 95%CI:[0.13;0.86], p=0.023) and females (adjusted OR: 0.14, 95%CI:[0.03;0.62], p=0.010). In the AOM 400 group, mean serum prolactin concentration decreased from baseline to week 28, while an increase was observed in the PP group. Six patients (all PP-treated) exhibited prolactin-related treatment-emergent adverse events. Conclusions: Superior improvements in health-related quality of life and functioning on QLS suggested greater effectiveness for AOM 400 vs PP, and improvements were accompanied by a lower risk for sexual dysfunction with AOM 400 vs PP treatment.