Welireg Belzutifan Tablets

1. Indications and Usage
Von Hippel-Lindau (VHL) Disease:
Indicated for the treatment of adult and pediatric patients (12 years and older) with VHL disease requiring therapeutic intervention for renal cell carcinoma (RCC), central nervous system (CNS) hemangioblastomas, or pancreatic neuroendocrine tumors (pNETs), not requiring immediate surgery.
Advanced Renal Cell Carcinoma (RCC):
Indicated for the treatment of adult patients with advanced RCC who have been treated with prior anti-PD-1/L1 inhibitor and anti-angiogenic therapy.
2. Dosage and Administration
Recommended Dosage:
Dose: 120 mg orally once daily.
Duration: Continue until disease progression or unacceptable toxicity.
Administration: Swallow tablets whole; do not crush or chew. Can be taken with or without food.
Dose Modifications:
Anemia: Interrupt if Hemoglobin < 8 g/dL; resume at reduced dose when ≥ 8 g/dL.
Hypoxia: Interrupt if resting oxygen saturation < 88%; resume at reduced dose when resolved.
3. Mechanism of Action
HIF-2α Inhibition:
Belzutifan is a small molecule inhibitor of hypoxia-inducible factor-2α (HIF-2α).
Physiological Effect:
It binds to the HIF-2α protein, blocking its interaction with HIF-1β. This inhibits the transcription and expression of HIF-2α target genes involved in angiogenesis (e.g., VEGF), cell proliferation, and tumor growth.
4. Safety and Warnings
Anemia:
Anemia occurs frequently and can be severe. Monitor hemoglobin levels prior to treatment and regularly during treatment.
Hypoxia:
Hypoxia may occur, sometimes requiring oxygen supplementation or hospitalization. Monitor oxygen saturation levels.
Embryo-Fetal Toxicity:
Can cause fetal harm. Verify pregnancy status before starting. Advise females of reproductive potential to use effective non-hormonal contraception during treatment and for 1 week after the final dose.
5. Adverse Reactions
Most Common (≥20%):
Anemia, fatigue, headache, dizziness, hypoxia, diarrhea, nausea, musculoskeletal pain, elevated creatinine, hyperglycemia, and cough.
6. Drug Interactions
UGT2B17 or CYP2C19 Inhibitors:
May increase belzutifan exposure. Monitor for anemia and hypoxia and consider dose reduction.
Hormonal Contraceptives:
May reduce the efficacy of hormonal contraceptives. Use non-hormonal methods.
7. Pharmaceutical Information
Chemical Composition:
Active Ingredient: Belzutifan.
Storage:
Store at 20°C to 25°C (68°F to 77°F); excursions permitted to 15-30°C (59-86°F). Protect from moisture.