Adherence to, and effectiveness of, subcutaneous interferon β-1a administered by RebiSmart® in patients with relapsing multiple sclerosis: results of the 1-year, observational SMART study

Abstract

Background: Patients with multiple sclerosis who have poor adherence to treatment have a higher risk of relapse than adherent patients. This study assessed adherence to, and effectiveness and convenience of, treatment with subcutaneous (sc) interferon (IFN) β-1a (Rebif®, Merck Serono SA) 44 or 22 μg three times weekly in patients with relapsing multiple sclerosis (RMS) using the RebiSmart® electronic, multidose, autoinjector for 1 year.

Study design: European, multicentre, observational study among neurologists: inclusion criteria included RMS, Expanded Disability Status Scale score ≤ 6, sc IFN β-1a administered by RebiSmart for ≤ 6 weeks. The primary endpoint was cumulative adherence recorded by RebiSmart.

Results: The safety population included 912 patients, 77.4% (n = 823) of whom completed the Month-12 visit. Mean (± standard deviation) cumulative adherence was 97.1 ± 7.3% (n = 791). The most common reason for missed injection was ‘forgot to inject’ (37.0%). At Month 12/ED, 79.5% of patients were relapse-free. Of 353 patients who rated the convenience of the device, 68.3% found injecting ‘very easy’. No unknown safety issues were detected.

Conclusions: Patients with RMS self-injecting sc IFN β-1a with RebiSmart had excellent adherence at Month 12/ED, which was associated with good clinical outcomes and no unexpected safety issues. Patients rated RebiSmart as convenient and easy to use.

Keywords:

• adherence
• autoinjector
• interferon β
• multiple sclerosis

Acknowledgments

The SMART study is registered with the ClinicalTrials.gov NCT01108887. Data have been presented in part as poster at the 66th Annual Meeting of the American Academy of Neurology (AAN), April 26th to May 3rd, 2014, Philadelphia. The authors thank Dr Ron Hogg of OmniScience S.A., Geneva, Switzerland (supported by Merck Serono SA, Geneva, Switzerland, a subsidiary of Merck KGaA, Darmstadt, Germany) for assistance in drafting a former version of this manuscript.

Declaration of interest

A Bayas has received honoraria for consulting and as a speaker from Merck Serono, Biogen-Idec, Bayer Vital, Novartis, and Sanofi/Genzyme; for advisory board activities from Teva; for trial activities from Merck Serono, Biogen-Idec, and Novartis; and received grants for congress trips and participation from Biogen-Idec, Sanofi/Genzyme, and Merck Serono. JC Ouallet has received consultancy fees and speaker fees from Merck Serono for this study, and received consultancy fees, speaker fees, research grants (non-personal), and honoraria from Novartis, Biogen-Idec, Merck Serono, Bayer Schering, Roche, Teva, and Sanofi/Genzyme. B Kallmann has received honoraria for serving on advisory boards and as a speaker from Merck Serono, Biogen-Idec, Sanofi/Genzyme, Teva, and Novartis. R Hupperts received honoraria for speaker’s performances, advisory boards, and research grants from Biogen, Genzyme-Sanofi, Merck, Novartis, and TEVA. U Fulda is an employee of Merck Serono GmbH, Darmstadt, Germany. K Marhardt is an employee of Merck GmbH, Vienna, Austria. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.

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