Presentation (CTI)

OBJECTIVES: To assess the long-term clinical effectiveness, treatment patterns, durability of disease control, and drug acquisition costs of oral cladribine in a real-world cohort of patients with multiple sclerosis (MS).
METHODS: A retrospective single-center observational study included patients with MS initiating cladribine between 2018 and 2024 at a tertiary referral center. Demographic, clinical and treatment data were extracted from medical records via hospital system (Glintt®). Outcomes included treatment completion, clinical stability, retreatment, subsequent disease-modifying therapy (DMT) and drug costs.
RESULTS: A total of 143 patients were included; 75,5% were female and the median age at cladribine initiation was 44 years (range19-70). Overall 18,9% of patients did not complete treatment due to failure (33,3%), dropout (29,6%) and 25,9% ongoing treatment. Among 116 patients completed treatment, 68,1% remained clinically stable, 19,8% switched to another DMT, 10,3% required retreatment, and 1,8% transferred center. Retreatment occurred predominantly during year 4 (41,7%). Twenty-six patients (18,2%) were treatment-naïve, while the remainder most commonly switched from dimethyl fumarate (24,8%), teriflunomide (18,8%) and interferon beta (16,2%). Among patients initiating a subsequent DMT, 39.2% transitioned to ofatumumab and 34,8% to ocrelizumab. In patients completing two cladribine courses, 43.1% remained clinically stable for >4 years, including 7.0% who maintained stability for 7 years. Durable disease stability (>48 months) was most frequently observed when cladribine was initiated as a second or third-line therapy (32% each). Mean annual drug costs among treatment-free patients declined from €8,136 during Years 3-4 to €4,649 in Year 7. At 48 months, cumulative cladribine costs were 28.6% and 33.2% lower than first- and second-line DMTs, respectively.
CONCLUSIONS: In this real-world cohort, cladribine was associated with sustained long-term clinical stability, prolonged treatment-free intervals and lower cumulative drug costs than conventional DMT treatment sequences. Durable outcomes and lower long-term costs highlight the potential cladribine’s value as an efficient MS treatment strategy.