A Cost per Responder Model for Abatacept versus Adalimumab Among Rheumatoid Arthritis Patients with Seropositivity

PURPOSE: The primary objective of this study was to compare the cost per responder (CPR) between abatacept and adalimumab among seropositive rheumatoid arthritis (RA) patients. PATIENTS AND METHODS: CPR analysis was conducted from a US payer perspective over 24 weeks for early moderate-to-severe seropositive RA patients. Efficacy data (American College of Rheumatology [ACR] improvement criteria [ACR20/50/70] and DAS28-C reactive protein <2.6) for abatacept and adalimumab were sourced from the post hoc analysis of the Early AMPLE trial (NCT02557100). Medication costs were considered assuming complete adherence. A 30% rebate was applied for adalimumab in the base case. RESULTS: At week 24, the total per patient pharmacy cost was $26,273.34 and $21,731.18, whereas the CPR (using ACR70 as the responder definition) was $46,337.46 and $74,935.10 (difference of -$28,597.64) for abatacept and adalimumab, respectively. The CPR was consistently lower for abatacept compared to adalimumab across all clinical measures, with differences ranging from -$7099.32 to -$43,608.97. CONCLUSION: While the pharmacy cost was higher for abatacept compared to adalimumab, due to its higher clinical efficacy, the CPR was consistently lower for seropositive RA patients treated with abatacept. The results may be useful for healthcare decision-makers in understanding how to optimize treatment for seropositive RA patients while minimizing costs in today’s budget-constrained health environment.