Belzutifan (Welireg) is a prescription medication indicated for the treatment of von Hippel-Lindau (VHL)-associated renal cell carcinoma (RCC), central nervous system (CNS) hemangioblastomas, or pancreatic neuroendocrine tumors (pNET).

What Are the Purchase Channels for Belzutifan (Welireg)?

Overseas Purchase

Patients may choose to consult and purchase the medication at hospital pharmacies or licensed drugstores in countries or regions where belzutifan has been approved for marketing.

As drug prices may be affected by factors such as regional differences and exchange rate fluctuations, patients need to make a budget and plan in advance before purchasing.

Purchase via Medical Service Institutions

Patients can consult domestic overseas medical service institutions that cooperate with international pharmacies or pharmaceutical companies.

These institutions can usually provide legal import channels, along with professional consultation and guidance services.

Precautions for Belzutifan (Welireg)

Essential Evaluations Before Treatment Initiation

Pregnancy Verification: Prior to the start of treatment, it is mandatory to verify the pregnancy status of females of reproductive potential. Use of this product during pregnancy may cause harm to the fetus.

Hematological and Oxygen Saturation Monitoring: Hemoglobin levels (to prevent anemia) and oxygen saturation (to prevent hypoxia) should be tested before treatment.

Patient Counseling: Physicians must inform patients and their partners about the risk of embryo-fetal toxicity, and instruct them to use effective non-hormonal contraceptive methods. This is because this product may render certain hormonal contraceptives ineffective. Contraceptive measures should be continued for 1 week after the last dose.

Dosage, Administration and Missed Dose Management

Recommended Dose: 120 mg, taken orally once daily, with or without food. The medication should be taken at the same time each day.

Administration Method: The tablets must be swallowed whole; do not chew, crush, or split the tablets.

Missed Dose and Vomiting Management: If a dose is missed, take it as soon as possible on the same day it is remembered, and resume the regular dosing schedule at the original time the next day. Do not take a double dose to make up for the missed dose. If vomiting occurs after taking the medication, do not take an extra dose, and take the next scheduled dose at the regular time the following day.

Drug Interactions

Avoid co-administration with sensitive CYP3A4 substrates (such as certain statins and antiarrhythmic drugs), as this product may reduce their plasma concentrations, which could lead to treatment failure.

Co-administration with UGT2B17 or CYP2C19 inhibitors may increase the plasma concentration of belzutifan, thereby potentially increasing the risk and severity of anemia and hypoxia. Close monitoring is required, and consideration should be given to reducing the dose of this product.

How to Identify the Authenticity of Belzutifan (Welireg)?

Verify the Source and Packaging

Source Tracing: Ensure that the medication is obtained directly with a doctor’s prescription from a licensed pharmacy. Verify that the manufacturer indicated on the bottle label is Merck Sharp & Dohme Corp.

Packaging Integrity: Check that the bottle seal is intact and that the bottle cap is a child-resistant closure. The bottle should contain two desiccant cans (not for consumption).

Label Information: Verify that the drug name (WELIREG), active ingredient (Belzutifan), strength (40 mg), and NDC number (0006-5331-01) are clearly and accurately printed, and consistent with the prescription.

Tablet Appearance: According to the official description, belzutifan tablets are blue, oval, film-coated tablets, engraved with “177” on one side and blank on the other. Upon receiving the medication, check the tablets against this description.