Objectives: To compare comorbidity-related outcomes, adherence to antipsychotics (APs), healthcare resource utilization (HRU), and costs pre- and post-transition to once-every-3-months paliperidone palmitate (PP3M) in commercially-insured patients with schizophrenia.
Methods: Adults with ≥1 claim for PP3M, ≥2 schizophrenia diagnoses, and adequate treatment with once-monthly paliperidone palmitate (PP1M; i.e. no gap of >45 days in PP1M coverage for ≥4 months, same PP1M dosage for the last two PP1M claims, and appropriate PP1M to PP3M dosing conversion) were selected from the IQVIA PharMetrics Plus database (May 2014-February 2018). Generalized estimating equation models adjusted for repeated measurements were used to compare patient characteristics, adherence to APs, HRU, and costs during the 6-month period pre- vs post-transition to PP3M.
Results: Of 152 included patients, the mean age was 41.0 years and 36.2% were females. Post-PP3M transition, patients were less likely to have a claim with a diagnosis for substance-related and addictive disorders (odds ratio [OR] = 0.57), psychoses (OR = 0.57), diabetes without chronic complication (OR = 0.72), and drug abuse (OR = 0.64; all p < .05). Patients were more likely to be adherent to APs (OR = 2.01, p = .007), compared to the period pre-PP3M transition. There was no significant difference in HRU pre- vs post-transition. All-cause total (mean monthly cost difference [MMCD] = $242), pre-rebate pharmacy (MMCD = $65), and medical costs (MMCD = $176) remained similar pre- vs post-transition (all p > .05).
Conclusions: Transitioning to PP3M was associated with an improvement in adherence and in comorbidity-related outcomes related to substance-related and addictive disorders, psychoses, diabetes without chronic complication, and drug abuse. These findings suggest PP3M may enhance comorbidity-related outcomes and adherence while remaining cost neutral.
Keywords: Antipsychotic agents; Delivery of healthcare; Healthcare costs; Medication adherence; Paliperidone palmitate; Schizophrenia.