Long-term effectiveness in patients previously treated with cladribine tablets: a real-world analysis of the Italian multiple sclerosis registry (CLARINET-MS)

Francesco Patti; Andrea Visconti; Antonio Capacchione; Sanjeev Roy; Maria Trojano; CLARINET-MS Study Group

doi:10.1177/1756286420922685

Long-term effectiveness in patients previously treated with cladribine tablets: a real-world analysis of the Italian multiple sclerosis registry (CLARINET-MS)

Ther Adv Neurol Disord. 2020 Jun 10:13:1756286420922685. doi: 10.1177/1756286420922685. eCollection 2020.

Authors

Francesco Patti¹, Andrea Visconti², Antonio Capacchione², Sanjeev Roy³, Maria Trojano⁴; CLARINET-MS Study Group

Affiliations

¹ Azienda Ospedaliera-Universitaria, "Policlinico Vittorio Emanuele", Catania via Santa Sofia 78, Catania, 95123, Italy.
² Merck Serono S.p.A., Rome, Italy, an affiliate of Merck KGaA, Darmstadt, Germany.
³ Merck, Aubonne, Switzerland, a division of Merck KGaA, Darmstadt, Germany.
⁴ Department of Basic Medical Sciences, Neurosciences and Sense Organs, University of Bari, Italy.

Abstract

Background: The CLARINET-MS study assessed the long-term effectiveness of cladribine tablets by following patients with multiple sclerosis (MS) in Italy, using data from the Italian MS Registry.

Methods: Real-world data (RWD) from Italian MS patients who participated in cladribine tablets randomised clinical trials (RCTs; CLARITY, CLARITY Extension, ONWARD or ORACLE-MS) across 17 MS centres were obtained from the Italian MS Registry. RWD were collected during a set observation period, spanning from the last dose of cladribine tablets during the RCT (defined as baseline) to the last visit date in the registry, treatment switch to other disease-modifying drugs, date of last Expanded Disability Status Scale recording or date of the last relapse (whichever occurred last). Time-to-event analysis was completed using the Kaplan-Meier (KM) method. Median duration and associated 95% confidence intervals (CI) were estimated from the model.

Results: Time span under observation in the Italian MS Registry was 1-137 (median 80.3) months. In the total Italian patient population (n = 80), the KM estimates for the probability of being relapse-free at 12, 36 and 60 months after the last dose of cladribine tablets were 84.8%, 66.2% and 57.2%, respectively. The corresponding probability of being progression-free at 60 months after the last dose was 63.7%. The KM estimate for the probability of not initiating another disease-modifying treatment at 60 months after the last dose of cladribine tablets was 28.1%, and the median time-to-treatment change was 32.1 (95% CI 15.5-39.5) months.

Conclusion: CLARINET-MS provides an indirect measure of the long-term effectiveness of cladribine tablets. Over half of MS patients analysed did not relapse or experience disability progression during 60 months of follow-up from the last dose, suggesting that cladribine tablets remain effective in years 3 and 4 after short courses at the beginning of years 1 and 2.

Keywords: cladribine tablets; clinically isolated syndrome; effectiveness; long-term data; multiple sclerosis; real-world data; real-world evidence; registry; relapsing-remitting MS; secondary progressive MS.