Background/Purpose: Rheumatoid arthritis (RA) is associated with pain, fatigue, disability and functional loss, which can significantly impact a patient’s health-related quality of life (HRQoL). Patient-Reported Outcomes (PROs) are critical since patients and caregivers do not always perceive treatment effects equally. To highlight the patient’s perspective, we report multiple PROs from the first head-to-head study, AMPLE (Abatacept Versus Adalimumab Comparison in Biologic Naive RA Subjects with Background Methotrexate) comparing subcutaneous abatacept (ABA) and adalimumab (ADA) on background methotrexate (MTX).

Methods: AMPLE is an ongoing, phase IIIb, randomized, investigator-blinded study of 24 months duration with a 12 month efficacy primary endpoint. Biologic-naïve patients with active RA and inadequate response to MTX were randomized to either 125 mg ABA weekly or 40 mg ADA bi-weekly in combination with MTX. PROs assessed were patient pain, patient global assessment (PtGA), and fatigue, all assessed by 100mm visual analog scale (VAS), with a higher score indicating worse outcome (Minimal Clinically Important Difference [MCID]: reduction ≥10mm). Physical function was evaluated with the health assessment questionnaire disability index (HAQ-DI; MCID reduction ≥0.3). HRQoL was assessed using the SF-36 (including Physical and Mental Component Summary subscores [PCS and MCS]; MCID: improvement ≥5). The Routine Assessment of Patient Index Data (RAPID3), an index of 3 patient-reported core dataset measures (physical function, pain, and patient global estimate of status), was also assessed (MCID: reduction ≥2.0).

Results: A total of 646 patients were randomized and treated with ABA (n=318) or ADA (n=328) on background MTX. Patient characteristics were balanced. A similar proportion of patients achieved a HAQ-DI response from baseline to year 1 (60.4% patients in the ABA arm vs. 57.0% patients in the ADA arm). Improvements in patient pain (mean% ± SE) were 46.5 ± 4.2% vs. 35.6 ± 4.1% at 6 months, and 53 ± 6.1% vs. 39.2 ± 6.0% at 1 year for ABA and ADA, respectively. Improvements in PtGA were 40.2 ± 7.3% vs. 27.6 ± 7.2% and 46.1 ± 3.5% vs. 41.2 ± 3.4% for ABA and ADA at 6 months and 1 year. Fatigue decreased from baseline by -22.4 ± 1.5% vs. -19.9 ± 1.5% at 6 months, and -23.2 ± 1.5% vs. -21.4 ± 1.5% at 1 year for ABA and ADA respectively. Improvements in all domains of the SF-36 including PCS and MCS observed at 6 months were maintained at 1 year (Figure). For RAPID3, the ABA and ADA-treated groups demonstrated improvements (mean ± SE) of -2.7 ± 0.1 vs. -2.5 ± 0.1 at 6 months and -2.9 ± 0.1 vs. -2.7 ± 0.1 at 1 year.

Conclusion:  In this first head-to-head comparison, subcutaneous abatacept demonstrated significant improvements with similar kinetics of response in patient-reported outcomes and HRQoL measures over 1 year which were comparable to adalimumab.