High persistence and low adverse events burden in cladribine treated MS patients from Argentina.

ABSTRACT

BACKGROUND: Early initiation with high efficacy therapies seems to be better than an escalation approach in terms of disability prevention in patients with relapsing-remitting MS (RRMS). Although efficacy and safety of cladribine tablets have been shown in clinical trials, real-world evidence (RWE) studies from Latin America are scarce. OBJECTIVE: To describe the baseline characteristics of patients enrolled in the Argentina Patient Support Program (PSP) for cladribine tablets (Adveva®), with at least 1 treatment course, evaluate treatment persistence, adverse event reports from PSP patients and reported relapses characterization. METHODS: Anonymized data routinely collected by Adveva® team of patients that received the first dose of cladribine from April 16th 2018 to March 31st 2021 were analyzed. Treatment persistence was defined as the percentage of patients that initiated year 2 (Y2) from the population of patients with elapsed time since year 1 (Y1) cladribine tablet initiation of at least 18 months. In addition, using the pharmacovigilance data, reported adverse events and the time elapsed from treatment initiation to relapse were analyzed. RESULTS: The present analysis included 269 patients (mean age 41.7 ± 16 years) that had initiated Y1 of cladribine tablets treatment between April 16th 2018 and March 31st 2021. Although only 29.4% (79/269) of our population was treatment naïve, the ratio of naïve/switch patients that initiated cladribine tablets increased from April 2018-March 2019 to April 2020-March 2021. From the 110 patients with elapsed time since treatment initiation ≥18 months, 101 patients initiated Y2 indicating a persistence level of 91.8%. During follow-up, 425 adverse events were reported, mainly MS relapse (8.9%, 38/425), fatigue (3.8%, 16/425) and headache (3.5%, 15/425). Lymphopenia and infections were rarely reported by RRMS patients treated with cladribine tablets. MS relapse was more frequently reported in patients switching from a previous treatment (87.5%, 27/32) than in the naïve cohort (12.5%, 5/32). CONCLUSIONS: The first real life experience in RRMS patients from Latin America demonstrated that the Adveva® enrolled support program patients have a high persistence level to oral treatment with cladribine tablets. Our results also confirmed the known safety profile of cladribine tablets, with a low incidence of lymphopenia and infections.