Patient-reported Outcomes from a Randomized Phase III Trial of Sarilumab Monotherapy Versus Adalimumab Monotherapy in Patients with Rheumatoid Arthritis

Background: The phase III MONARCH randomized controlled trial (NCT02332590) demonstrated that in patients with rheumatoid arthritis (RA), sarilumab (anti-interleukin-6 receptor monoclonal antibody) monotherapy is superior to adalimumab monotherapy in reducing disease activity and signs and symptoms of RA, as well as in improving physical function, with similar rates of adverse and serious adverse events. We report the effects of sarilumab versus adalimumab on patient-reported outcomes (PROs).

Methods: Patients with active RA intolerant of, or inadequate responders to, methotrexate were randomized to sarilumab 200 mg plus placebo every 2 weeks (q2w; n = 184) or adalimumab 40 mg plus placebo q2w (n = 185). Dose escalation to weekly administration of adalimumab or matching placebo was permitted at week 16. PROs assessed at baseline and weeks 12 and 24 included patient global assessment of disease activity (PtGA), pain and morning stiffness visual analogue scales (VASs), Health Assessment Questionnaire Disability Index (HAQ-DI), 36-item Short Form Health Survey (SF-36), Functional Assessment of Chronic Illness Therapy-Fatigue (FACIT-F), Rheumatoid Arthritis Impact of Disease (RAID), and rheumatoid arthritis-specific Work Productivity Survey (WPS-RA). Between-group differences in least-squares mean (LSM) changes from baseline were analyzed. p < 0.05 was considered significant for PROs in a predefined hierarchy. For PROs not in the hierarchy, nominal p values are provided. Proportions of patients reporting improvements greater than or equal to the minimal clinically important difference (MCID) and achieving normative values were assessed.

Results: At week 24, sarilumab treatment resulted in significantly greater LSM changes from baseline than adalimumab monotherapy in HAQ-DI (p < 0.005), PtGA (p < 0.001), pain VAS (p < 0.001), and SF-36 Physical Component Summary (PCS) (p < 0.001). Greater LSM changes were reported for sarilumab than for adalimumab in RAID (nominal p < 0.001), morning stiffness VAS (nominal p < 0.05), and WPS-RA (nominal p < 0.005). Between-group differences in FACIT-F and SF-36 Mental Component Summary (MCS) were not significant. More patients reported improvements greater than or equal to the MCID in HAQ-DI (nominal p < 0.01), RAID (nominal p < 0.01), SF-36 PCS (nominal p < 0.005), and morning stiffness (nominal p < 0.05), as well as greater than or equal to the normative values in HAQ-DI (p < 0.05), with sarilumab versus adalimumab.

Conclusions: In parallel with the clinical efficacy profile previously reported, sarilumab monotherapy resulted in greater improvements across multiple PROs than adalimumab monotherapy.

Trial Registration: ClinicalTrials.gov, NCT02332590 . Registered on 5 January 2015.