To study the effectiveness and the safety of Cladribine treatment in MS patients in a real-world clinical setting.

Cladribine was approved for treatment of multiple sclerosis (MS). Real-world data is very limited.

This observational, prospective study included MS patients who had at least one year follow-up after second course of Cladribine treatment. Baseline patient clinical and radiological characteristics recorded within one year prior to Cladribine initiation. The relapse rate, disability measures, radiological activity and adverse events at last visit were assessed.

A total of seventy-two patients, 59 (81.9%) were females, mean age 36.32 +10.06 years old, mean disease duration 7.21+6.19. Most patients (n=32; 44.4%) were nai¨ve to any treatment. Forty patients (55.6%) completed two courses of treatment. At the end of observational period, most of our cohort was relapse free (85% versus 25%; P<0.001) and few had new T2 lesions (7.5% versus 70.8%; P<0.001 and gadolinium enhancement 5% versus 66.7%; P<0.001) in MRI compared to baseline. ARR was significantly reduced 0.15 +0.36 versus 0.85+0.53; P<0.01). Most of cohort 90% has no progression of disability. No evidence of disease activity 3 (NEDA-3) was achieved in 30 (75%) patients. It was achieved in 87.5% of naive patients versus 66.7% in patients who received prior disease modification drugs before Cladribine initiation. Infections 6 (n=6; 8.4%) lymphocytopenia (n=3; 4.2%), and elevated liver enzymes (n=1; 1.4%) were reported.

The effectiveness and safety profile of cladribine in this study were consistent with data of phase 3 clinical trials. Early initiation of cladribine is associated with favorable outcome.