Immune thrombocytopenic purpura associated with fingolimod

Fingolimod is an oral sphingosine-1-phosphate receptor modulator which causes lymphocyte sequestration in lymph nodes and is approved for relapsing multiple sclerosis. The Therapeutic Goods Administration of Australia is aware of only one case where fingolimod preceded immune thrombocytopenic purpura (ITP) by 5 weeks. Here we report three such cases.None were on any medications known to cause ITP and routine investigations were unremarkable. All cases were treated with immunosuppression. Case 1 successfully weaned prednisolone after fingolimod cessation whereas case 2 weaned slowly while continuing fingolimod therapy. Case 3 had more refractory ITP and re-exposure to fingolimod worsened thrombocytopenia.There was a temporal association between fingolimod exposure and ITP however dose-effect association and pathogenesis remain less clear.In conclusion, our cases highlight that clinicians should be aware of the possible association between ITP and fingolimod.