Enasidenib is an isocitrate dehydrogenase-2 (IDH2) inhibitor used for the treatment of adult patients with relapsed or refractory acute myeloid leukemia (AML) who harbor IDH2 mutations.

How to Use Enasidenib

Administration Regimen

Recommended Dose: 100mg orally once daily, which can be taken with or without food.

Treatment Course: Continue medication until disease progression or unacceptable toxicity occurs. To assess clinical response, a treatment duration of at least 6 months is recommended.

Administration Requirements: Swallow the tablet whole; do not split or crush it. If a dose is missed or vomiting occurs, take the missed dose as soon as possible on the same day, and resume the normal dosing schedule the next day. Do not take a double dose to make up for the missed one.

Dose Adjustment of Enasidenib

Dose Adjustment for Differentiation Syndrome

Management: Immediately initiate corticosteroid therapy (e.g., dexamethasone 10mg every 12 hours) and conduct hemodynamic monitoring when differentiation syndrome is suspected.

Dose Adjustment: If severe pulmonary symptoms requiring intubation/ventilator support or renal dysfunction persist for more than 48 hours occur, suspend enasidenib. Resume medication after symptoms improve to grade ≤2.

Dose Adjustment for Non-Infectious Leukocytosis

Management: Hydroxyurea is the first-line treatment. If hydroxyurea is ineffective, suspend enasidenib and resume the 100mg daily dose once the white blood cell (WBC) count drops to <30×10⁹/L.

Dose Adjustment for Elevated Bilirubin

When bilirubin >3× upper limit of normal (ULN) persists for ≥2 weeks without abnormal liver enzymes, reduce the dose to 50mg daily.

After bilirubin returns to <2×ULN, the dose can be increased back to 100mg daily.

Medication for Special Populations of Enasidenib

Pregnant and Lactating Women

Pregnancy Risk: Animal studies have shown that enasidenib has embryo-fetal toxicity and may cause teratogenicity. Women of childbearing age must confirm a negative pregnancy status before medication use, and use highly effective contraceptive measures during treatment and for 1 month after the last dose.

Lactation: Breastfeeding is prohibited; avoid breastfeeding for at least 1 month after the last dose.

Patients with Hepatic or Renal Impairment

Hepatic Function: No dose adjustment is needed for mild hepatic impairment (bilirubin ≤ULN with AST >ULN, or bilirubin 1-1.5×ULN). Data on moderate to severe hepatic impairment are insufficient.

Renal Function: No dose adjustment is needed for patients with a creatinine clearance ≥30mL/min. Data on patients with more severe renal impairment are limited.