Abstract General Information

Title

Weight Loss in Multiple Sclerosis Therapy: A Rare Adverse Effect of Fingolimod

Case Report

Case presentation: A 25-year-old woman was diagnosed with relapsing-remitting multiple sclerosis (RRMS) in 2021 and started treatment with dimethyl fumarate. In August 2022, she presented a new lesion with gadolinium enhancement in the right cerebellar peduncle, associated with gastrointestinal adverse effects of the medication. For this reason, the change to fingolimod was indicated and started 2 months later. The patient had an unintentional weight loss of 5 kg in 3 months of medication use, unrelated to dietary changes, initiation of intense and regular physical activity, and without other adverse effects of the medication.

Discussion: Fingolimod is a sphingosine-1-phosphate (S1PR) receptor modulator. S1P receptors are present in various organic tissues with the potential for adverse effects such as headache, elevated liver enzymes, diarrhea, cough, flu and low back pain. S1PR are present in the ventromedial and dorsomedial hypothalamic groups including anorexigenic neurons with action on leptin-melanocortin circuits. We found reports of weight loss associated with the use of fingolimod in only three cases in the literature. A retrospective study (2022) reported an incidence of 11.4% of significant weight loss, defined as a loss of 4.5 kg or 5% of body weight after initiation of fingolimod, suggesting that this adverse effect may be more frequent than previously observed.

Final comments: Dietary guidelines as well as evaluation of changes in appetite and weight, should be observed in patients after initiation of treatment with fingolimod. In addition, more research is needed to clarify the effect of fingolimod on patients weight.