Severe infections in pediatric MS and related disorders patients on B-cell depleting therapies compared to sphingosine-1-receptor modulators.

BACKGROUND

There is limited data on infection risk in pediatric onset multiple sclerosis and related disorders (MSARD).

OBJECTIVES

Analyze rate of severe infections in pediatric MSARD patients on B-cell depleting therapies (BCT) compared to fingolimod.

METHODS

This was a retrospective chart review of pediatric MSARD patients from the Harvard Multiple Sclerosis Patient Database and the MGH Pediatric Multiple Sclerosis Center database treated with BCT or fingolimod. Infections were defined as severe if requiring hospitalization, or if there were two outpatient infections within six months requiring more than standard antibiotics.

RESULTS

Forty one patients were identified: 24 on fingolimod and 22 on BCT. Five received fingolimod and then switched to BCT. The rate of severe infections per year was 0.065(0.028,0.128) in the BCT and 0.008(0.0002,0.047) in the fingolimod group. The rate ratio was 7.6; 95 %CI:0.91,64.5;p = 0.061. There was no difference in relapse rate between groups. There was increased radiographic activity in the fingolimod group (0.474 MRIs/year) compared to the BCT group (0.154 MRIs/year) p = 0.002.

CONCLUSIONS

In this small cohort of pediatric MSARD patients on BCT and fingolimod, severe infections were rare. There was a trend towards increased infections with BCT. Clinical relapse rates were similar while fingolimod patients had more radiographic activity.