ivosidenib
Tibsovo (ivosidenib) is an oral targeted therapy from Servier for acute myeloid leukaemia carrying an IDH1 mutation. It blocks the mutant enzyme's abnormal product, letting blocked blood cells mature again, alone or with azacitidine.
This page is based on FDA prescribing information and the EMA medicine record for ivosidenib, cross-checked with DailyMed and MedlinePlus; the mechanism is explained in plain language, and analogies are used only where they stay accurate.
How it works
Explains what the medicine does in the body, not dosing, side effects, or safety.
An analogy
The IDH1 mutation turns a normal workshop enzyme into one that churns out a counterfeit chemical, 2-HG, which jams the maturation program of young blood cells. Ivosidenib switches the rogue machine off. The counterfeit stops accumulating, the jam clears, and the blood cells finally grow up and do their jobs.
In simple terms
Some acute myeloid leukaemias carry a mutation in the IDH1 gene. The mutant enzyme produces an abnormal substance, 2-hydroxyglutarate, that prevents young blood cells from maturing. Ivosidenib specifically inhibits the mutant IDH1 enzyme, so the abnormal substance falls. Released from the maturation block, leukaemia cells can differentiate and die normally, and healthy blood cell production recovers.
In depth
Ivosidenib is an oral, selective small-molecule inhibitor of mutant IDH1 (R132 variants). It suppresses production of the oncometabolite 2-hydroxyglutarate, reversing epigenetic blockade of differentiation and inducing maturation of malignant myeloid blasts. In newly diagnosed AML unfit for intensive chemotherapy, combining ivosidenib with azacitidine improved event-free and overall survival versus azacitidine alone.
See it in motion
A schematic animation of the mechanism — simplified for clarity, not drawn to scale.
How IDH inhibitors work
- Mutant IDH1 in leukaemia cells makes the abnormal metabolite 2-hydroxyglutarate instead of the normal product.
- That abnormal metabolite blocks blood-cell maturation and helps maintain the leukaemia state.
- The drug binds the mutant enzyme’s active site, so 2-hydroxyglutarate production falls.
- With the metabolic block lifted, immature leukaemia cells can mature and the disease burden decreases.
Target: Mutant isocitrate dehydrogenase-1 (IDH1)
A mutated metabolic enzyme that floods leukaemia cells with the oncometabolite 2-hydroxyglutarate, blocking their maturation; inhibiting it removes the block and restores differentiation.
Approved uses
Approved uses differ by country and change over time. Always follow your local prescribing information.
Approved uses in United States
FDA- With azacitidine, or as monotherapy, for newly diagnosed acute myeloid leukemia with a susceptible IDH1 mutation, as detected by an FDA-approved test, in adults 75 years or older or with comorbidities that preclude intensive induction chemotherapy
- Treatment of adults with relapsed or refractory acute myeloid leukemia with a susceptible IDH1 mutation, as detected by an FDA-approved test
Approved uses in European Union
EMA- With azacitidine, for newly diagnosed acute myeloid leukaemia with an IDH1 R132 mutation in adults not eligible for standard induction chemotherapy
Official sources
The statements on this page trace back to these records.
- Tibsovo (ivosidenib) — Summary of product characteristics and package leaflet, English version
European Medicines Agency
- DailyMed: Tibsovo (ivosidenib) label
DailyMed, U.S. National Library of Medicine
- U.S. Food and Drug Administration: ivosidenib prescribing information
U.S. Food and Drug Administration
- MedlinePlus: ivosidenib
MedlinePlus, U.S. National Library of Medicine
- National Cancer Institute: ivosidenib
National Cancer Institute
This page explains how the medicine works — it isn’t the patient leaflet. For anything that applies to you, read the leaflet that came with your medicine or ask your pharmacist.
MedUnfold provides educational content and is not medical advice. Always follow your local prescribing information and healthcare professional.