Retention rate of a novel autoinjector e-Device introduced to patients with chronic arthritis treated with certolizumab pegol in clinical practice: an observational implementation study

Objectives
The objectives were to explore the clinical retention rate of an e-Device aimed at empowering chronic arthritis patients using certolizumab pegol (CZP) and to analyse beliefs about medication in the Danish population.

Method
Patients treated with CZP were recruited from the Netherlands, Denmark, and Sweden through rheumatology clinics at initiation of, or switching to, the e-Device. Patients were adults (aged 18–85 years) diagnosed with rheumatoid arthritis, axial spondyloarthritis, or psoriatic arthritis. Patients administered three consecutive self-injections at home. Descriptive statistics regarding baseline characteristics, retention rates, and reasons for withdrawal were assessed, along with the Beliefs about Medicines Questionnaire.

Results
In total, 59 patients participated (Netherlands 25, Denmark 15, Sweden 19). Most subjects (71%) were women, with a mean ± sd age of 55 ± 16.2 years and mean disease duration 12 ± 8.8 years. Six patients (10%) started CZP de novo and the remaining patients switched device. The overall retention rate was 42% after 52 weeks, declining to 38% after 104 weeks. A sharp decline, 34%, was seen at week 8. Between weeks 32 and 112, only four patients (6.8%) withdrew from the study. The primary reason for withdrawal was the patient’s request. Stratification by country showed significant differences for some outcomes.

Conclusion
An initial large dropout was evident within the first 8 weeks, with almost no dropouts thereafter. The reasons for withdrawal were primarily patient requests. Thus, the injection experience must be tailored carefully when selecting patients for new autoinjector e-Devices to enhance retention rates and patient satisfaction.