DMT69
Classic-MS: Long-Term Efficacy and Real-World Treatment Patterns for Patients with Relapsing Multiple Sclerosis Who Received Cladribine Tablets in Phase III Parent Trials

Tuesday, October 26, 2021
Exhibit Hall (Rosen Shingle Creek)
Gavin Giovannoni, MD, PhD , Blizard Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London, United Kingdom
Aida Aydemir, MSc , EMD Serono Research & Development Institute Inc., Billerica, MA, USA, an affiliate of Merck KGaA, Darmstadt, Germany, Billerica, MA
Elisabetta Verdun di Cantogno, MD, PhD , Merck KGaA, Darmstadt, Germany
Thomas P. Leist, MD , Comprehensive Multiple Sclerosis Center, Division of Clinical Neuroimmunology, Jefferson University, Philadelphia, PA



Background:

CLASSIC-MS (NCT03961204) explores the long-term efficacy and durability of effect of cladribine tablets (CladT; cumulative dose 3.5 mg/kg over 2 years) beyond the 2 annual treatment courses in patients with relapsing multiple sclerosis (MS) enrolled in CLARITY, with/without CLARITY Extension trials, with the aim of informing future treatment choices.

Objectives:

Interim analysis of long-term outcomes for patients with MS originally enrolled in the parent trials, as part of the CLASSIC-MS study.

Methods:

CLASSIC-MS is an exploratory, low-interventional, ambispective Phase IV study of patients previously enrolled into Phase III parent trials who had received ≥1 course of CladT or placebo. We report an interim analysis of long-term responder rates for a small population of patients with relapsing MS who were previously enrolled in CLARITY with/without CLARITY Extension. Long-term responder status was defined as: A) not requiring further disease-modifying therapy (DMT) treatment until ≥4 years after last parent study dose (LPSD), or B) no evidence of disease reactivation based on clinical outcomes in the 4 years following LPSD. Analyses are descriptive.

Results:

The interim population comprised 93 patients (61% female; mean EDSS score, 4.06±2.00 at CLASSIC-MS baseline), with a median time since LPSD of 10.4 (range 9.5─14.2) years; 93.5% were exposed to CladT in the parent trials. Overall, 82.8% were long-term responders by definition A, and 36.6% by definition B. In addition, 68.8% of patients enrolled to CLASSIC-MS received no subsequent DMT treatment after LPSD. 45% of participating patients were actively employed at the time of CLASSIC-MS enrollment.

Conclusions:

We report an interim analysis of a small population of patients with relapsing MS from CLARITY with/without CLARITY Extension who are participating in CLASSIC-MS. Findings show that while 3 out of 5 participating patients had disease reactivation during 4 years since LPSD, only 1 in 5 required further DMT treatment during these 4 years. Results from the full analysis set of the CLASSIC-MS study will be shown in the final presentation.