To define multiple sclerosis (MS) disease activity and neurologic outcomes after exposure to immune checkpoint inhibitors (ICIs) as cancer therapy.
ICIs are associated with immune-related adverse events (irAEs) as well as exacerbation of pre-existing autoimmune diseases. There are reports of ICIs triggering relapses in people with MS (pwMS); however, the incidence of ICI-induced MS activity is unknown.
PwMS who were treated with ICIs were identified by chart review at 8 tertiary medical systems. Participating sites were recruited through the Medical Partnership 4 MS+ (MP4MS+) listserv, a group comprising over 1,300 neurologists and allied health professionals dedicated to the treatment and management of MS. Using a structured instrument, we collected data on MS history, cancer history, treatments, and outcomes.
In this interim analysis, we identified 38 patients (71% female, median age 66 years) with MS (33 relapsing remitting, 4 progressive, and 1 radiologically isolated syndrome) who were treated with ICIs. Thirteen (34%) pwMS were on disease modifying therapy (DMT) immediately prior to ICI initiation and only 8 continued on DMT during ICI therapy. The most common primary tumors were lung (11, 29%) and melanoma (10, 26%). Only 1 pwMS (2.6%) had a relapse following ICI treatment and 1 patient had ongoing progressive disease, during mean of 13 months of follow-up after ICI initiation. Two patients (5%) had peripheral nervous system ICI irAEs, and 12 (32%) had a non-neurologic ICI irAEs. Thirteen (34%) subjects had either partial or complete remission of their cancer at last follow up. Results from an estimated 60 patients will be presented.
In this multi-institutional study of pwMS, who were predominantly older and not on DMT, MS relapses and disease progression following ICI treatment were uncommon.