# NEDA-3 using cladribine for multiple sclerosis: effectiveness data from a Norwegian hospital

## TL;DR

This study evaluates cladribine's effectiveness in treating multiple sclerosis in Norway, finding that one-third of patients showed no disease activity after three years.

## Contribution

The study provides real-world effectiveness data on cladribine for MS in a Norwegian hospital setting.

## Key findings

- 33% of patients achieved NEDA-3 three years after starting cladribine.
- Treatment-naïve patients had better outcomes compared to those with prior treatments.
- Mild to moderate adverse events occurred in 21.7% of patients.

## Abstract

Cladribine is an immunomodulatory agent used in the treatment of relapsing–remitting multiple sclerosis (MS) and, in some countries, for active progressive forms of MS. However, relatively few clinical observational studies have evaluated its effect.

This retrospective cohort study included all patients with multiple sclerosis who were treated with cladribine at Nordland Hospital between April 2018 and September 2024. We aimed to evaluate the effectiveness of cladribine by assessing No Evidence of Disease Activity (NEDA)-3 over time.

A total of 60 patients (62% women), of whom 58 had relapsing–remitting multiple sclerosis, 1 had radiologically isolated syndrome, and 1 had secondary progressive disease and received at least 1 cyclic treatment. The mean age at the initiation of cladribine was 38.5 ± 11.0 years, and the mean Expanded Disability Status Scale (EDSS) was 2.1 ± 1.3. Two-thirds (65%) of the patients had received other disease-modifying treatment before cladribine. During the study period, eight patients switched or discontinued treatment, seven due to disease activity, two due to self-financed autologous stem cell treatment, one due to a drug overdose, and one for an unclear reason. Compared to patients with evidence of disease activity (EDA), those achieving NEDA-3 after 2 years were older at MS onset (p = 0.046), and a larger proportion were treatment-naïve at the start of cladribine (42% vs. 11%, p = 0.03). NEDA-3 was achieved by 36 (60%) patients at 1 year, 24 (40%) at 2 years, and 20 (33%) at 3 years. Mild to moderate adverse events were observed or reported in 13 (21.7%) patients; 1 developed lymphocytopenia grade 3, and 1 developed herpes zoster.

One in three patients achieved NEDA-3 3 years after starting cladribine, with the best outcomes observed in treatment-naïve patients, while its favorable safety profile and convenient dosing support long-term adherence and disease stability.