Introduction: Sarilumab is a human monoclonal antibody that blocks the interleukin-6 receptor alpha (IL-6Rα). The phase 3 SARIL-RA-EASY study (EASY) assessed the robustness of an autoinjector (pen) for administering sarilumab when used by adults with active moderate-to-severe rheumatoid arthritis (RA) who are candidates for anti-IL-6R therapy in an unsupervised real-world setting.
Methods: EASY was a 12-week, multicenter, randomized, open-label, parallel-group usability study of the sarilumab pen and prefilled syringe. Patients were randomized 1:1:1:1 to sarilumab 150 or 200 mg every 2 weeks (q2w) administered via pen or syringe, plus background disease-modifying antirheumatic drugs. Patients reported their ability to remove the pen cap and initiate and complete injections; negative responses were defined as product technical complaints (PTCs). The primary endpoint was the number of validated product technical failures (PTFs; PTC with a validated technical cause). This study was not powered to demonstrate bioequivalence or differences in efficacy among groups.
Results: A total of 217 patients were randomized. There were 600 successful injections with the sarilumab pen in 108 patients and no pen-associated PTFs. One PTC was observed (the pen was mistakenly activated before injection). At week 12, 88% of patients indicated the pen was "easy" to use, and 98% reported they were "satisfied" with the pen. Proportions of patients achieving an American College of Rheumatology 20/50/70 response and a 28-joint disease activity score by C-reactive protein < 2.6 were similar at each dose between the pen and syringe groups, as were the pharmacokinetics. There were no clinically meaningful differences in adverse events (AEs), serious AEs, and AEs leading to discontinuation in the pen and syringe groups. The most common treatment-emergent AEs were infections and neutropenia.
Conclusion: This study demonstrated the ease of use and robustness of the sarilumab pen when used by patients with RA in an unsupervised setting. Pharmacokinetics, safety, and efficacy were generally similar for the pen and syringe groups (NCT02057250).
Funding: Sanofi Genzyme and Regeneron Pharmaceuticals, Inc.
Trial registration: Clinicaltrials.gov identifier, NCT02057250.
Keywords: Autoinjector; IL-6; IL-6Rα; Patient preference; Pen; Prefilled syringe; Rheumatoid arthritis; Sarilumab.