Treatment satisfaction, safety, and tolerability of cladribine tablets in patients with highly active relapsing multiple sclerosis: CLARIFY-MS study 6 month interim analysis

Bruno Brochet, Raymond Hupperts, Dawn Langdon, Alessandra Solari, Frederik Piehl, Jeanette Lechner-Scott, Xavier Montalban, Krzysztof Selmaj, Martin Valis, Konrad Rejdak, Eva Havrdová, Francesco Patti, Nektaria Alexandri, Axel Nolting, Birgit Keller

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Background: Multiple sclerosis (MS) is a chronic disabling disease that is associated with negative effects on health-related quality of life (HRQoL) due to reduced physical and psychosocial functioning. Cladribine tablets 10 mg (3.5 mg/kg cumulative dose over 2 years) have been approved for the treatment of adult patients with highly active relapsing multiple sclerosis (RMS). The ongoing CLARIFY-MS study (NCT03369665; EudraCT number: 2017-002632-17) aims to assess the effect of cladribine tablets 3.5 mg/kg on HRQoL of patients with highly active RMS.

Objective: To report on the design of the CLARIFY-MS study, baseline patient characteristics, and results of a pre-planned interim analysis focusing on treatment satisfaction, safety, and tolerability that includes all data reported till 6 months after start of treatment.

Methods: The CLARIFY-MS study is a 2-year, open-label, single-arm, prospective, multicenter, phase IV study. Eligible patients with highly active RMS were assigned to receive cladribine tablets 3.5 mg/kg over 2 years. Treatment satisfaction was assessed using the Treatment Satisfaction Questionnaire for Medication (TSQM, v1.4; scale range from 0 to 100, higher values indicating higher satisfaction). Safety assessments, including occurrence of treatment-emergent adverse events (TEAEs; any adverse event reported after drug administration), serious adverse events (SAEs), and lymphocyte counts, were summarized descriptively.

Results: A total of 482 patients from 85 sites in Europe were treated with cladribine tablets. Mean patient age was 37.4 years, 338 (70.1%) were women, median EDSS was 2.5, and 345 (71.6%) were prior users of disease-modifying therapy (DMT). During the first 6 months after the start of treatment, and before reaching the full dose of cladribine tablets, mean TSQM global satisfaction score for the overall population was 70.4 (standard deviation, ± 18.48). The side effects score was 91.9 (± 17.68), convenience scored 86.6 (± 13.57), and effectiveness was 65.8 (± 21.14). A total of 275 patients (57.1%) reported at least one TEAE and 9 patients (1.9%) had a SAE. The majority of observed lymphopenia cases were of grade 1 or 2; 33 (6.8%) of the total study cohort had grade 3 lymphopenia, and no grade 4 lymphopenia was reported.

Conclusion: Patients reported high treatment satisfaction (TSQM) with cladribine tablets in this pre-planned interim analysis at 6 months. Few serious, and no unexpected, adverse events were reported, and there were no instances of grade 4 lymphopenia over the first 6 months. These preliminary data indicate good tolerability and convenience of administration of cladribine tablets in patients with highly active RMS.
Original languageEnglish
Article number103385
JournalMultiple sclerosis and related disorders
Early online date9 Nov 2021
Publication statusE-pub ahead of print - 9 Nov 2021

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