Study Overview
Objective. To assess usability and patient perceptions of the sarilumab auto-injector device (“sarilumab pen”) among patients with moderate-to-severe rheumatoid arthritis (RA).
Design. 12-week, randomized, parallel-group usability study.
Setting and participants. The study was conducted at 53 centers in 6 countries. Inclusion criteria were a diagnosis of RA (as defined by American College of Rheumatology/ European League Against Rheumatism 2010 Criteria) of ≥ 3-month disease duration, willing and able to self inject, continuous treatment with 1 or a combination of nonbiologic disease modifying antirheumatic drugs (except leflunomide in combination with methotrexate); and moderatly to severely active RA, defined as 4/66 swollen joint, 4/68 tender joints, and high-sensitivity C-reactive protein (hsCRP) measurement ≥ 4 mg/L. Exclusion criteria were age
Patients were randomized 1:1:1:1 to sarilumamb 150 or 200 mg every 2 weeks administered by single-use, disposable, prefilled pen or pre-filled syringe. Randomization method was not reported.
Main outcomes measures. The primary endpoint was number of “product technical failures” (PTFs). Patients randomized to the pen were given a diary that had questions related to their ability to remove the cap, start the injection, and complete the injection. Participants were asked to answer the questions each time they used the pen. If the response was “no” to any of the 3 questions, this was considered a “product technical complaint” (PTC). PTCs that had a validated technical cause based on pen evaluation and analysis were considered PTFs.
In addition, patient perceptions and satisfaction with the pen were assessed via questionnaire. At baseline, patients were asked about injections and prior experience with self-injection, and at 12 weeks they were asked about their experiences in using the pen. Other outcomes assessed included adverse events and pharmokinetic parameters.
Results. 217 participants were enrolled: 108 patients were in the pen group (56 randomized to 150 mg and 52 randomized to 200 mg) and 109 were in the syringe group (53 randomized to 150 mg and 56 randomized to 200 mg). Completion rates were similar among groups. Sixteen patients discontinued due to treatment-emergent adverse events. There were no PTFs. There was one PTC, in which the user accidently bumped the pen, which expelled the drug onto the floor.
At baseline, before the first injection, the majority of patients reported that they were not afraid of needles (58%), had past experience with self-injections (55%), and were either “very confident” or “extremely confident” regarding self-injections (55%). After the 12-week assessment phase, when asked about their overall level of satisfaction, 98% of patients reported they were “satisfied” or “very satisfied” with the sarilumab pen.
Treatment emergent adverse events occurred in 66% of patients, with no clinically meaningful differences leading to discontinuation in the pen and syringe groups. The most common adverse events were infections and neutropenia.
Conclusion. Patients successfully completed self-injections with the sarilumab pen and found it easy to use.
Commentary
Rheumatoid arthritis (RA) is a common immune-mediated disease characterized by chronically progressive inflammation and destruction of joints and associated structures, resulting in significant morbidity, mortality, and disability. Improved understanding of RA disease pathogenesis in recent years has led to the development of new biologic treatments designed to target specific elements of the RA inflammatory response.
Sarilumab is an interleukin-6 blocker that was approved in the US in 2017 for the treatment of adult patients with moderately to severely active RA who have had an inadequate response or intolerance to one or more disease-modifying antirheumatic drugs. While a syringe form of this drug is currently available, at the time of this writing the pen has not yet been released.
In this real-world usability study sponsored by Sanofi, there were no technical difficulties with using the pen. Most patients thought the pen was easy or very easy to use, and safety and effeicacy appeared to be generally comparable between the pen and syringe. The pen also offers safety protection features that prevent needlestick injury.
The authors of the current study noted that results from previous studies have shown that patients with RA favor treatment devices that are easy to use, convenient, less painful, and take less time to use, and patients have demonstrated a preference for autoinjector devices over more conventional methods of treatment administration [1–3], such as syringes. Pens have been well accepted for the treatment of other chronic health conditions, including diabetes mellitus, migraine headaches, and growth hormone deficiency, and subcutaneous administration of a tumor necrosis factor (TNF) inhibitor via pen has also been accepted for the treatment of RA [1]. As RA requires lifelong treatment, the use of a pen that is ergonomically designed to take into account the manual dexterity issues relevant to this patient population could potentially enhance compliance.
Applications for Clinical Practice
A prefilled pen was well accepted and associated with favorable patient perceptions, indicating that this delivery system may be a viable option for RA patients who are prescribed sarilumab.