Belzutifan

Belzutifan is a targeted drug that is mainly used to treat specific types of malignant tumors such as kidney cancer, hemangioblastoma and pancreatic neuroendocrine tumors.

It inhibits tumor growth and angiogenesis by inhibiting HIF-2α and blocking the expression of genes associated with hypoxia adaptation and tumor growth.

Belzutifan has been approved by the Food and Drug Administration (FDA) of the United States and has been marketed in United States, United Kingdom, Canada and other countries and regions.

1. Main ingredient

 Belzutifan

2. Applicable people

Belzutifan is indicated for treatment of adult patients with von Hippel-Lindau (VHL) disease who require  therapy for associated renal cell carcinoma (RCC), central nervous system (CNS) hemangioblastomas, or  pancreatic neuroendocrine tumors (pNET), not requiring immediate surgery.  

3. Use in Specific Populations

 1 Pregnancy  

Based on findings in animal studies, Belzutifan can cause fetal harm when administered to a pregnant  woman. There are no available data on the use of Belzutifan in pregnant women to inform the drug associated risk. In an animal reproduction study, oral administration of belzutifan to pregnant rats during  the period of organogenesis caused embryo-fetal lethality, reduced fetal body weight, and fetal skeletal  malformations at maternal exposures ≥0.2 times the human exposure (AUC) at the recommended dose of  120 mg daily (see Data). Advise pregnant women and females of reproductive potential of the potential  risk to a fetus.  

The background risk of major birth defects and miscarriage for the indicated population is unknown. In the  U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically  recognized pregnancies is 2–4% and 15–20%, respectively.

2 Lactation  

There are no data on the presence of belzutifan or its metabolites in human milk or their effects on the  breastfed child or on milk production. Because of the potential for serious adverse reactions in a  breastfed child, advise women not to breastfeed during treatment with Belzutifan and for 1 week after the  last dose.

3 Females and Males of Reproductive Potential  

Belzutifan can cause fetal harm when administered to a pregnant woman.

4 Pediatric Use  

Safety and effectiveness of Belzutifan have not been established in pediatric patients.  

5 Geriatric Use  

Of the patients who received Belzutifan in Study 004, 3.3% were ≥65 years old [see Clinical Studies  (14)]. Clinical trials of Belzutifan did not include sufficient numbers of patients aged 65 and older to  determine whether they respond differently from younger patients.  

6 Renal Impairment  

No dosage modification of Belzutifan is recommended in patients with mild (eGFR 60-89 mL/min/1.73 m2  estimated by MDRD) and moderate (eGFR 30-59 mL/min/1.73 m2) renal impairment [see Clinical  Pharmacology (12.3)]. Belzutifan has not been studied in patients with severe (eGFR 15-29 mL/min/1.73  m2) renal impairment.  

7 Hepatic Impairment  

No dosage modification of Belzutifan is recommended in patients with mild [total bilirubin ≤ upper limit of normal (ULN) and aspartate aminotransferase (AST) > ULN or total bilirubin >1 to 1.5 x ULN and any  AST] hepatic impairment. Belzutifan has not been studied in patients with moderate or severe hepatic  impairment (total bilirubin >1.5 x ULN and any AST) 

8 Dual UGT2B17 and CYP2C19 Poor Metabolizers  

Patients who are dual UGT2B17 and CYP2C19 poor metabolizers have higher belzutifan exposures,  which may increase the incidence and severity of adverse reactions of Belzutifan. Closely monitor for  adverse reactions in patients who are dual UGT2B17 and CYP2C19 poor metabolizers

4. Over dosage

There is no specific treatment for Belzutifan overdose. In cases of suspected overdose, withhold  Belzutifan and institute supportive care. Grade 3 hypoxia occurred at dosages of 120 mg twice a day and  Grade 4 thrombocytopenia occurred at dosages of 240 mg once daily (approximately 2 times the  recommended dosage).

5. Storage

 Store at 20°C to 25°C (68°F to 77°F), excursions permitted between 15°C and 30°C (59°F and 86°F).

6. Pharmacokinetics

The mean steady-state (CV%) Cmax is 1.3 μg/mL (42%) and AUC0-24h is 16.7 µg•hr/mL (52%) in patients  with VHL disease-associated RCC. Steady state is reached after approximately 3 days. Cmax and AUC  increase proportionally over a dose range of 20 mg to 120 mg (0.17 to 1 times the approved  recommended dose).

FDA，2021.08