Abstract:

Purpose: Tacrolimus is available as generic twice-daily immediate release capsules (IR-Tac) or branded once-daily extended-release tablets (LCPT). LCPT has lower peak concentrations compared to IR-Tac, but prescribers may be concerned about the cost of LCPT compared to IR-Tac. We evaluate the out-of-pocket (OOP) costs (defined as final amount charged to the patient) of LCPT vs IR-Tac in kidney transplant patients and the OOP costs covered by the institution’s financial assistance, Medication Access Program (MAP). MAP provides financial support to qualifying uninsured or underinsured patients.

Methods: This was a single-center, retrospective review of pharmacy and billing claims records from 1/1/2021 - 06/30/22. Kidney transplant recipients who filled prescriptions for IR-Tac or LCPT with the center’s transplant pharmacy were included. Patients must have filled two or more 30-day fills or one or more 90- day fills of LCPT or IR-Tac. Patients less than 18 years old or with no insurance coverage were excluded. Descriptive statistics were used to summarize the amount of OOP costs covered by secondary insurance and by MAP in patients without secondary insurance coverage at prescriptions fill level. Ordinal logistic regression analysis was used to compare the OOP & total medication costs for prescriptions filled for LCPT and IR-TAC at patient level after controlling for patient demographics and insurance type.

Results: A total of 18411 fills were included (n=16262 IR-Tac, n=2149 LCPT). Patients prescribed IR-Tac averaged OOP costs of $8.10 (standard deviation [SD]

26.2) compared to patients prescribed LCPT with an average OOP cost of $5.20 (SD 33). Secondary insurance reduced 2241 OOP fill costs (n=1969 IR-Tac, n=272 LCPT), covering an average of $42.10 for IR-Tac fills and $152.96 for LCPT fills. After primary insurance, MAP covered an average of $32.74 for IR-Tac fills and

$198.53 for LCPT fills in patients without secondary insurance. Patients prescribed LCPT were significantly less likely to have a higher OOP cost (odds ratio [OR]

0.16 [0.09, 0.3], p<0.001). Compared to commercial insurance, patients with Medicaid and Medicare were significantly less likely to have a higher copay (OR 0.22 [0.13, 0.38] and OR 0.17 [0.14, 0.22], p<0.001, respectively). Average OOP costs for patients with primary insurance and no secondary plan, primary insurance and a non-MAP secondary plan, primary insurance and MAP was as follows: IR-Tac: $11.67, $0, $0; LCPT: $7.66, $0, $0.

Conclusions: At an institution with assistance to cover OOP costs in eligible patients, patients prescribed LCPT were less likely to have higher OOP cost than those prescribed IR-Tac. However, patients with a high copay or deductible primary insurance plan without secondary insurance or access to assistance are at risk for high OOP costs for both IR-Tac and LCPT.