Tibsovo unlocks new era for rare blood cancers called myelodysplastic syndromes

On 24 October, the FDA approved Servier Pharmaceuticals LLC’s Tibsovo (ivosidenib) for individuals with relapsed or refractory myelodysplastic syndromes (MDS) carrying an isocitrate dehydrogenase-1 (IDH1) mutation, ushering in a new era in MDS treatment. This approval, a first biomarker-driven therapy for MDS, marks a major advancement in an area where there have been limited treatment options.

MDS are a class of bone marrow disorders with a variety of genotypes and phenotypes that induce inefficient haematopoiesis and an increased risk of acute myeloid leukaemia (AML). According to a GlobalData epidemiology study, the number of five-year diagnosed prevalent cases of MDS in the US will reach 107,603 by 2028, highlighting the need for novel treatments. Notably, Tibsovo has emerged as a promising treatment option for the 1.5% of MDS patients who have the IDH1 mutation. Tibsovo targets and inhibits the mutant IDH1 enzyme to disrupt aberrant cell activity in MDS, restoring normal blood cell formation and reducing disease progression.

Tibsovo’s efficacy was examined in a Phase I trial (study AG120-C-001, NCT02074839) on 18 persons with MDS who had an IDH1 mutation detected using Abbott Laboratories‘s RealTime IDH1 Assay. The key outcomes were remission rates and the duration of remission. The complete or partial remission was 39% (seven out of 18). All reported responses were full remissions, with a median response duration of 21.4 months and a median time to complete remission of 1.9 months. Six of nine MDS patients who needed blood or platelet transfusions at the start of the study no longer needed them after Tibsovo treatment. However, it is paramount to be aware of the drug’s associated boxed warning, a possible adverse response called differentiation syndrome, which can be lethal if untreated. According to GlobalData’s consensus analyst forecast, global sales for Tibsovo are expected to reach a modest $179m by 2029. However, as IDH1 is mutated in about 2.85% of all cancers, the label expansion to solid tumours is a possibility. The drug is currently evaluated in 13 Phase I, II, and III clinical trials globally for several solid malignancies, including bile duct cancer, osteosarcoma, rare pediatric tumours, and low-grade glioma. Furthermore, Tibsovo’s FDA breakthrough therapy and orphan drug designations will validate Servier Pharmaceuticals LLC’s investment in researching treatments for rare disorders