FDA Approval Summary: Ivosidenib for Treatment of Adult Patients with Relapsed/Refractory Myelodysplastic Syndrome with an IDH1 Mutation

On October 24th, 2023, the FDA approved a supplemental application for ivosidenib (Tibsovo; Servier) for the treatment of adult patients with relapsed/refractory (R/R) IDH1-mutated myelodysplastic syndrome (MDS). The efficacy of ivosidenib in patients with R/R MDS was established in study AG120-C-001, an open-label, single-arm trial, based on complete remission (CR) + partial remission (PR) rate, duration of CR + PR, and conversion of transfusion dependence (TD) to transfusion independence (TI). With a median follow-up of 27.1 months in 18 patients with IDH1-mutated R/R MDS treated with ivosidenib 500mg once daily, the CR + PR rate was 39% (95% CI: 17.3-64.3) (all CR responses), with a median duration of response not estimable (range 1.9, 80.8+ months). Of the 9 patients that were TD at baseline, 6 achieved TI (67%). Serious adverse reactions in ≥5% included differentiation syndrome, fatigue, and rash. The most common (≥20%) adverse reactions were arthralgia, fatigue, cough, diarrhea, decreased appetite, mucositis, myalgia, and pruritis.