VANCOUVER, BC—Disease-modifying treatments in relapsing-remitting multiple sclerosis (RRMS) showed similar effects in those whose disease onset was in childhood compared with adult onset, investigators reported at the 68th AAN Annual Meeting.

Noting “a paucity of clinical trial data” with disease-modifying treatments in pediatric-onset MS, Teesta Soman, MD, MBA, Associate Director, Global Medical Affairs, Biogen, Cambridge, MA, and colleagues investigated whether the effect of disease-modifying treatments differed if initiated at onset in children vs. adults by examining individual patient level data from four randomized Phase 3 adult trials.

Using an integrated database from the placebo-controlled AFFIRM, DEFINE, CONFIRM, and ADVANCE trials, they performed subgroup analyses based on age at onset of relapsing-remitting MS. Pediatric onset MS was defined as 10 to 18 years of age and adult onset, greater than 18 years.

Of 3,487 adult patients, 9% had MS onset in childhood. At baseline, the pediatric subgroup was an average of 10 years younger, “slightly more” non-white, “and had more previous steroid treatment and higher MRI activity” than the adult onset MS subgroup, Dr. Soman reported.

Annualized relapse rate was 56% in the pediatric-onset MS subgroup compared with 53% for the adult-onset MS subgroup; new/newly enlarging T2 lesions on MRI were 66% vs. 81%; and Gd+ lesions were 74% vs. 89%, respectively. The time to 12-week confirmed Expanded Disability Status Scale (EDSS) progression was 52% in the pediatric-onset MS subgroup compared with 37% in the adult-onset MS subgroup, they reported.

“These findings suggest that treatment with DMTs [disease-modifying therapies] is beneficial in adult patients with RRMS regardless of age of disease onset,” they concluded.