New Versus Old Injectable Antipsychotics for Schizophrenia
San Diego—Long-acting injectable (LAI) antipsychotics are highly effective in the management of schizophrenia and associated with a number of potential advantages over oral antipsychotics. First-generation LAIs (LA1s) have been available for more than 50 years, while second-generation LAIs (LA2s) have only become available in the past decade to treat schizophrenia. Real-world evidence comparing treatment patterns, healthcare resource utilization, and costs of schizophrenia patients on LAI1 versus LAI2 are limited. To further examine these 3 parameters, researchers compared patients on once-monthly generic haloperidol decanoate (ie, a LAI1) and once-monthly paliperidone palmitate (ie, a LAI2).
Researchers presented the findings at the AMCP meeting during a poster session titled Comparing Healthcare Cost among Patients with Schizophrenia Treated with First- versus Second-Generation Long- Acting Injectable Antipsychotics.
Using data from the Truven Health Analytics MarketScan® databases, adults ≥18 years of age with any schizophrenia form initiating LAI from 2007 to 2013 (date of initiation=index date) were identified from commercial, Medicare supplemental, and Medicaid claims databases. Eligible patients had continuous enrollment with ≥6 months pre- and ≥1-year post- index period. Patients were matched on baseline characteristics and comorbidities. Wilcoxon rank-sum and Chi-square tests were used to compare healthcare resource utilization and relapse events, cost, and treatment patterns at 1-year post-index date. A total of 538 pairs of LAI1 and LAI2 were matched on mean age, gender, insurance, psychiatric comorbidities (eg, bipolar, depression, anxiety, alcohol abuse, substance abuse), and Charlson comorbidity index.
At 12 months follow-up, patients in the paliperidone palmitate cohort had greater adherence compared with the haloperidol decanoate cohort. For example, the paliperidone palmitate group had more LAI in- jections and days of LAI coverage (8.9 and 241.2, respectively) compared with the haloperidol decanoate group (5.8 and 156.5, respectively). The paliperidone palmitate cohort also had lower discontinuation of medication (21.6% vs 48.5%, respectively). Discontinuation was defined by gap of >60 days between injections. In terms of the number of healthcare resource utilization events during the 12-month follow-up period, the paliperidone palmitate cohort had fewer emergency room visits, a greater number of physician visits, and greater assertive community treatment visits (1.8, 23.75, and 5.2, respectively) compared with the haloperidol decanoate cohort (2.8, 16.9, and 3.7, respectively). All-cause mean and total number of healthcare resource utilization events including inpatient hospitalizations, relapse, and 7- and 30-day re-admissions were comparable between the cohorts.
When researchers looked at the all-cause healthcare costs per patient per month, they found that the total cost was higher for the paliperidone palmitate cohort versus the haloperidol decanoate cohort ($3034 vs $2164, respectively), a contributing factor may be the cost difference between the brand versus generic drug. Paliperidone palmitate costs $1245 per month, while haloperidol decanoate costs $435 per month, according to the study. However, emergency room visits were relatively lower for the paliperidone palmitate group compared with the haloperidol decanoate group ($66 vs $104, respectively).
The investigators indicated limitations associated with the study, including that the analysis did not account for switching during the post-index period and pharmacy claims may or may not reflect actual administration or use of product. Also, prescription cost did not take rebates and discounts into account and only direct healthcare costs based on plan and patient out-of-pocket payments for each service was assessed.
In summary, the researchers concluded, “It is im- portant to note from the high discontinuation rate and low adherence observed in the LAI1 cohort that patients may not respond to or tolerate all antipsychotic medications. Thus, it is important that this vulnerable population with frequent adherence issues have access to multiple (if not all) available antipsychotic medications.”—Eileen Koutnik-Fotopoulos
This study was supported by Janssen Scientific Affairs, LLC.
