Valemetostat, as an EZH2 inhibitor, is contraindicated mainly to individuals with special physiological conditions and drug interaction risks. During medication, it is necessary to strictly avoid specific foods and disease states. The following classification details the contraindications and restrictions.

1. Taboo population

(1) Pregnant women: with embryo fetal toxicity, prohibited during pregnancy. Pregnancy status should be verified before treatment, and effective contraception should be used during the medication period and within 6 months after the last dose.

(2) Breastfeeding women: Medications may be secreted into breast milk. Breastfeeding is prohibited during treatment and for one week after discontinuation of medication.

(3) Severe liver function impairment: Not recommended for Child Pugh C patients, dosage adjustment is necessary for moderate to mild impairment.

(4) Individuals allergic to active ingredients: permanent discontinuation of medication is required if vascular edema or severe rash occurs.

2. Forbidden foods

(1) Grapefruit and its products: significantly inhibit CYP3A4 metabolic enzymes, leading to a 2-3 fold increase in blood drug concentration.

(2) High fat diet: Postprandial administration leads to a 35% increase in AUC, it is recommended to take on an empty stomach.

(3) Alcoholic beverages: may increase the metabolic burden on the liver and induce elevated transaminase levels.

3. Restrictive conditions

(1) Cardiovascular disease: Risk of QT interval prolongation. Hypokalemia should be corrected before medication, and regular monitoring of electrocardiogram is necessary.

(2) Hematological system diseases: The incidence of thrombocytopenia is about 30%, and blood routine is monitored weekly during treatment.

(3) Combination therapy: Strong CYP3A4 inhibitors/inducers need to be adjusted in dosage to avoid combination with anticoagulants such as warfarin.

4. Special population restrictions

(1) Children: The safety and efficacy of patients under 18 years old have not been established.

(2) Elderly patients: Patients aged 65 and above need to reduce the starting dose as the clearance rate decreases by 40%.

(3) Renal insufficiency: Patients with end-stage renal disease should use it with caution, and moderate damage does not require dose adjustment.