Overview
11 DESCRIPTION Enasidenib is an inhibitor of isocitrate dehydrogenase-2 (IDH2) enzyme. Enasidenib is available as the mesylate salt with the chemical name: 2-methyl-1-[(4-[6-(trifluoromethyl)pyridin-2-yl]-6-{[2-(trifluoromethyl)pyridin-4-yl]amino}-1,3,5-triazin-2-yl)amino]propan-2-ol methanesulfonate.
Mechanism of Action
12 CLINICAL PHARMACOLOGY 12.1 Mechanism of Action Enasidenib is a small molecule inhibitor of the isocitrate dehydrogenase 2 (IDH2) enzyme. Enasidenib targets the mutant IDH2 variants R140Q, R172S, and R172K at approximately 40-fold lower concentrations than the wild-type enzyme in vitro. Inhibition of the mutant IDH2 enzyme by enasidenib led to decreased 2-hydroxyglutarate (2-HG) levels and induced myeloid differentiation in vitro and in vivo in mouse xenograft models of IDH2 mutated AML. In blood samples from patients with AML with mutated IDH2, enasidenib decreased 2-HG levels, reduced blast counts and increased percentages of mature myeloid cells. 12.
Indications
- 1 INDICATIONS AND USAGE IDHIFA is an isocitrate dehydrogenase-2 inhibitor indicated for the treatment of adult patients with relapsed or refractory acute myeloid leukemia (AML) with an isocitrate dehydrogenase-2 (IDH2) mutation as detected by an FDA-approved test ( 1.1 ). 1.1 Acute Myeloid Leukemia IDHIFA is indicated for the treatment of adult patients with relapsed or refractory acute myeloid leukemia (AML) with an isocitrate dehydrogenase-2 (IDH2) mutation as detected by an FDA-approved test.
Common Doses
- 100 mg
- 50 mg
Dosage
2 DOSAGE AND ADMINISTRATION 100 mg orally once daily until disease progression or unacceptable toxicity ( 2.2 ). 2.1 Patient Selection Select patients for the treatment of AML with IDHIFA based on the presence of IDH2 mutations in the blood or bone marrow [see Indications and Usage (1.1) and Clinical Studies (14.1) ] . Information on FDA-approved tests for the detection of IDH2 mutations in AML is available at http://www.fda.gov/CompanionDiagnostics . 2.
Black Box Warning
WARNING: DIFFERENTIATION SYNDROME Patients treated with IDHIFA have experienced symptoms of differentiation syndrome, which can be fatal if not treated. Symptoms may include fever, dyspnea, acute respiratory distress, pulmonary infiltrates, pleural or pericardial effusions, rapid weight gain or peripheral edema, lymphadenopathy, bone pain, and hepatic, renal, or multi-organ dysfunction. If differentiation syndrome is suspected, initiate corticosteroid therapy and hemodynamic monitoring until symptom resolution [see Warnings and Precautions (5.1) and Adverse Reactions (6.1) ] .
Contraindications
- 4 CONTRAINDICATIONS None. None ( 4 ).
Side Effects
- 6 ADVERSE REACTIONS The following clinically significant adverse reactions are described elsewhere in the labeling: • Differentiation Syndrome [see Warnings and Precautions (5.1) ] The most common adverse reactions (≥20%) are nausea, vomiting, diarrhea, elevated bilirubin, and decreased appetite ( 6.1 ). To report SUSPECTED ADVERSE REACTIONS, contact Bristol Myers Squibb at 1-800-721-5072 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch. 6.
Interactions
- 7 DRUG INTERACTIONS • Certain CYP1A2 and CYP2C19 Substrates: Avoid concomitant use unless otherwise recommended in the Prescribing Information ( 7.1 ). • Certain CYP3A Substrates: Avoid concomitant use unless otherwise recommended in the Prescribing Information ( 7.1 ). • Certain OATP1B1, OATP1B3, and BCRP Substrates: Avoid concomitant use unless otherwise recommended in the Prescribing Information ( 7.1 ). 7.1 Effect of IDHIFA on Other Drugs Certain CYP1A2 Substrates Avoid concomitant use with IDHIFA unless otherwise recommended in the Prescribing Information for CYP1A2 substrates where...