P.081 Evolving treatment of pediatric-onset multiple sclerosis in Alberta

Background: Pediatric-onset multiple sclerosis (MS) is associated with a high rate of disease activity. However, only a single DMT – fingolimod – has been approved by Health Canada for children, in 2018. In this study, we describe trends in the treatment of pediatric-onset MS in Alberta. Methods: We performed a retrospective review of Alberta administrative health databases, identifying cases of MS under 19 years of age from January 1, 2011 - December 31, 2020. Pharmacy dispenses of MS DMTs were identified by Anatomical Therapeutic Chemical classification code and grouped as injectables (glatiramer acetate, interferon-beta) or newer agents (all others). Results: 79 incident cases of pediatric MS were identified during the study period. 47/79 (59%) had at least one DMT dispense, with the first dispense occurring a median 263 days (IQR 134.5-988) from the index date at a median age of 17.2 years (IQR 16.0-18.6). Injectables accounted for all initial DMT dispenses < 19 years of age prior to 2019, while from 2019-2020 injectables accounted for only 3/15 (20%) initial dispenses, with rituximab (5/15, 33%) being the most common initial DMT in those years. Conclusions: The treatment of children with MS in Alberta has rapidly evolved, shifting shift towards earlier treatment using newer high-efficacy agents.