Safety, Efficacy of Cladribine for Relapsing-Remitting MS: Real-World Data

The use of oral cladribine is a safe and effective treatment for relapsing-remitting multiple sclerosis (RRMS), according real-world evidence presented at the Annual Meeting of the Consortium of Multiple Sclerosis Centers (CMSC), held from June 1 to 4, 2022 in National Harbor, Maryland.

Prior clinical trial data suggest the potential increased risk for malignancy caused by cladribine is a cause for concern. No follow-up studies have assessed the increased risk for malignancy while on cladribine, prompting this real-world data study.

Researchers followed 50 patients with RRMS treated with oral cladribine at a single MS center for a median of 490.5 days. Patients with MS recruited for the study were mostly female (72%). Mean age of the patients was 48 years, while mean number of years following initial diagnosis of MS was 9.7 years.

The researchers collected real-world data, including prior treatment using other disease-modifying therapies (DMTs) before cladribine, adverse events (AEs), serum lymphocyte and immunoglobulin levels, and annualized relapse rate (ARR).

Prior to treatment with cladribine, 94% of the 50 patients in this study received the DMTs — most commonly natalizumab (54%), ocrelizumab (10%), and glatiramer acetate (10%).

Mostly mild AEs occurred with only 1 patient discontinuing treatment due to an AE. Only 1 patient did not respond to cladribine, necessitating rescue therapy.

After analysis of serum lymphocyte and immunoglobulin levels, grade 0 to 2 lymphopenia occurred in 44 of 49 patients (90%), and severe grade 3 lymphopenia occurred in 6 of 49 patients (12%). None of the patients developed malignancies, grade 4 lymphopenia, or severe infections due to lymphopenia.

ARR during cladribine treatment was 0.06 compared with 0.3 during previous treatment with other DMTs. During the study period, 3 patients each experienced 1 relapse.

“This cohort study provides real-world data demonstrating the efficacy and safety of cladribine in patients with RRMS,” the researchers stated. “These are similar findings to previous clinical trial data.”

Disclosure: Some study authors declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of authors’ disclosures.

Reference

Kaplan T, Kaplan J. Real world findings in an oral cladribine cohort study in patients with multiple sclerosis. Presented at: CMSC 2022 Annual Meeting; June 1-4, 2022; National Harbor, Maryland. Abstract DMT56.