High adherence to treatment with cladribine tablets for multiple sclerosis during the COVID-19 pandemic: Results from patient support programmes

Introduction: Cladribine tablets (CladT) are taken as 2 short annual courses for the treatment of multiple sclerosis (MS), with treatment indications differing by country. Adveva® is a nurse/ pharmacy-led patient support programme (PSP) that provides drug education and support to patients taking CladT, and collects treatment-related clinical information. Objectives: Evaluate treatment adherence during Year 2 of treatment with CladT in Australia, Canada, and the UK, and whether there was an effect of the COVID-19 pandemic on treatment adherence. Methods: PSP data routinely collected from Australia, Canada, and the UK between 05Dec2017 (launch of CladT in first participating country) and 28Feb2021 (cut-off date) were included in this analysis. Demographics and date of treatment initiation of Year 1 and Year 2 were recorded. Patients were monitored using telephone check-in from treatment initiation until cut-off date, loss to follow-up, or treatment discontinuation. Time to Year 2 of treatment initiation was estimated overall and in two periods (before and during COVID-19) defined by the start date of the pandemic in each country (Australia: 13Mar2020;Canada: 16Mar2020;UK: 23Mar2020). Results: Overall, 3,536 patients initiated CladT during the study period (Australia, n=598;Canada, n=1,973;UK, n=965). Approximately 76% were female in each country. Most had received prior disease-modifying therapy (Australia, 75.6%;Canada, 100%;UK, 44.1%). Among patients with at least 18 months of follow-up since Year 1 initiation, the vast majority had initiated Year 2 of treatment (Australia, n=415 [90.6%];Canada, n=1213 [90.8%];UK, n=578 [88.0%]). The mean time to Year 2 initiation in Australia, Canada, and the UK was 13.02 (standard deviation [SD]: ±2.02), 13.15±1.95, and 14.45±2.71 months, respectively. Mean time (months ±SD) to initiation of Year 2 treatment was similar before and during the COVID-19 pandemic in all countries (Australia: 12.49±1.01 and 13.87±2.81;Canada: 12.79±1.33 and 13.43±2.28;UK: 13.28±1.25 and 15.47±3.19). Among those initiating Year 2 of treatment, a delay of at least 6 months to initiation of dosing was seen for 4.1% of patients in Australia, 2.7% in Canada, and 7.6% in the UK. Conclusions: Treatment adherence to CladT was high and consistent between participating countries, and was not influenced by the COVID-19 pandemic. The existence of a robust nurse/pharmacy- led PSP enables valuable data collection and likely facilitates adherence.