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.