Background: Self-administration of subcutaneous interferon beta-1a (sc IFN β-1a) can be achieved with the RebiSmart® electromechanical autoinjector. This study investigated adherence to, and duration of persistence with, the newest version of the device (v1.6) among 2644 people receiving sc IFN β-1a for multiple sclerosis (MS).
Research design and methods: This retrospective, observational study utilized data from RebiSmart® devices, recorded on the MSdialog database, between January 2014 and November 2019. Adherence and persistence were evaluated over a 3-year period and assessed in relation to age, sex, injection type, and injection depth.
Results: The population of RebiSmart® users (N = 2644) comprised of 1826 (69.1%) females and mean age was 39 (range 16-83) years. Adherence to RebiSmart® use and data transfer to the MSdialog database was consistently high (mean 91.7%; range 86.8-92.6%), including across all variables (81.6-100%). Mean (±SD) persistence during the study period was 1.35 ± 1.06 years, with a maximum recorded persistence of 5.1 years. In multivariate analysis, the longest durations of persistence were observed among older individuals and males (p < 0.0001 and p = 0.0078, respectively).
Conclusions: People living with MS were highly adherent to use of the RebiSmart® device, with higher persistence generally observed for older and/or male individuals.
Keywords: Adherence; RebiSmart® device; interferon beta-1a; multiple sclerosis; persistence.
It is important for people living with multiple sclerosis (MS) to take their medication regularly – and to keep doing so – in order to control their symptoms. Some people with MS receive a medication called interferon beta-1a (Rebif®) as a subcutaneous injection (given just under the skin), and the RebiSmart® electromechanical autoinjector was designed to help them to self-inject such medication. This study aimed to find out whether people were using the RebiSmart® device as often as they should be, and how long they continued to use it for. Information was taken from the MSdialog database, which recorded peoples' use of the RebiSmart® device between January 2014 and November 2019. Records for 2644 people using the device were analyzed. Results showed that the RebiSmart® device was used most of the time (around 91.7%). On average, people kept using the device for around a year and 4 months before stopping. This duration was generally longer for men compared with women, and longer for older people than younger people. These results increase our understanding of how people are using the RebiSmart® device to treat their MS symptoms.