Shift to Earlier Treatment, Access to More DMTs Improved Outcomes in Pediatric-Onset MS

The shift to treat patients with pediatric-onset multiple sclerosis (POMS) who are treated earlier with a wider variety of medications has led to better outcomes, according to a study published in Children.

The findings come from a study at Great Ormond Street Hospital and Evelina London Children’s Hospital comparing patients seen in the 2007-2010 period (earlier cohort) and in the 2015-2016 period (later cohort). The researchers compared these cohorts to understand changing management and clinical outcome of patients.

“Early treatment is recognised to improve adult long-term outcomes, and previous challenges in managing children with MS included significant delays in diagnosis and access to treatments,” the authors explained.

There were 24 patients in the earlier cohort and 27 in the later cohort. Demographics were similar between the 2 cohorts, as was tie from first symptoms to diagnosis (median 10 months in earlier cohort and 9 months in the later cohort).

In the earlier cohort, 19 patients (79%) were commenced on disease-modifying therapies (DMTs) compared with 24 patients (89%) in the later cohort. The later cohort also initiated their first DMT much quicker after diagnosis (median 3.5 months vs 9.0 months; P = .013). While interferon beta-1a was the most commonly used initial DMT for both cohorts, 4 new DMTs were introduced after 2010, so the interferon beta-1a accounted for a smaller proportion in the later cohort (59%) vs the earlier cohort (79%). Natalizumab was introduced in 2010, fingolimod in 2014, dimethyl fumerate in 2015, and alemtuzumab in 2017.

The majority (63%) of patients who started on DMT across both cohorts relapsed during a 36-month follow-up. The relapse rate was significantly higher in the earlier cohort (84%) vs the later cohort (46%). The mean annualized relapse rate (ARR) before DMT initiation was also higher in the earlier cohort (2.7) compared with the later cohort (1.7), and the mean ARR throughout the course of treatment with DMT was 0.74 in the early cohort compared with 0.37 in the later cohort.

A larger proportion of patients in the later cohort underwent neuropsychological assessment (89%) compared with the earlier cohort (58%). The researchers found that the later cohort performed better with higher Spelling, Word Reading, and Delayed Memory z-scores. However, after they adjusted for the longer time to assessment in the earlier cohort, only Word Reading z-scores were significantly improved with no significant differences in Spelling and Delayed Memory.

The authors noted the retrospective nature of the study was a key limitation, and they added that it “remains unclear as to what extent service factors are responsible for differing patterns of treatment between cohorts.” In addition, the small sample size limits statistical power and the fact that patients in the cohorts had different baseline relapse rates meant there could be no direct comparison of treatment efficacy.

“Although we cannot ascribe improvements seen to any single factor, the cohort of patients treated earlier, more holistically and with newer DMTs are likely to experience multiple downstream effects predominantly in relapse rates,” the researchers concluded. “Secondary benefits would include fewer hospital admissions, fewer courses of steroid treatment, fewer missed school days and less residual disability resulting from irreversible neuronal loss.”

Reference

Smith AL, Benetou C, Bullock H, et al. Progress in the management of paediatric-onset multiple sclerosis. Children (Basel). Published online November 9, 2020. doi:10.3390/children7110222