Belzutifan

1 INDICATIONS AND USAGE WELIREG is a hypoxia-inducible factor inhibitor indicated: von Hippel-Lindau (VHL) disease 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. ( 1.1 ) Renal Cell Carcinoma with a Clear Cell Component (ccRCC) in combination with pembrolizumab or pembrolizumab and berahyaluronidase alfa-pmph, for the adjuvant treatment of adult patients with ccRCC at intermediate-high or high risk of recurrence following nephrectomy, or following nephrectomy and resection of metastatic lesions. ( 1.2 ) as monotherapy, for treatment of adult patients with advanced ccRCC following a programmed death receptor-1 (PD-1) or programmed death-ligand 1 (PD-L1) inhibitor and a vascular endothelial growth factor tyrosine kinase inhibitor (VEGF-TKI). ( 1.2 ) Pheochromocytoma or Paraganglioma (PPGL) for treatment of adult and pediatric patients 12 years and older with locally advanced, unresectable, or metastatic pheochromocytoma or paraganglioma (PPGL). ( 1.3 ) 1.1 von Hippel-Lindau (VHL) disease WELIREG 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. 1.2 Renal Cell Carcinoma with a Clear Cell Component (ccRCC) WELIREG, in combination with pembrolizumab or pembrolizumab and berahyaluronidase alfa-pmph, is indicated for the adjuvant treatment of adult patients with ccRCC at intermediate-high or high risk of recurrence following nephrectomy, or following nephrectomy and resection of metastatic lesions. WELIREG is indicated for the treatment of adult patients with advanced ccRCC following a programmed death receptor-1 (PD-1) or programmed death-ligand 1 (PD-L1) inhibitor and a vascular endothelial growth factor tyrosine kinase inhibitor (VEGF-TKI). 1.3 Pheochromocytoma or Paraganglioma (PPGL) WELIREG is indicated for the treatment of adult and pediatric patients 12 years and older with locally advanced, unresectable, or metastatic pheochromocytoma or paraganglioma (PPGL).

12.1 Mechanism of Action Belzutifan is an inhibitor of hypoxia-inducible factor 2 alpha (HIF-2α). HIF-2α is a transcription factor that plays a role in oxygen sensing by regulating genes that promote adaptation to hypoxia. Under normal oxygen levels, HIF-2α is targeted for ubiquitin-proteasomal degradation by VHL protein. Lack of functional VHL protein results in stabilization and accumulation of HIF-2α. Upon stabilization, HIF-2α translocates into the nucleus and interacts with hypoxia-inducible factor 1 beta (HIF-1β) to form a transcriptional complex that induces expression of downstream genes, including genes associated with cellular proliferation, angiogenesis, and tumor growth. Belzutifan binds to HIF-2α, and in conditions of hypoxia or impairment of VHL protein function, belzutifan blocks the HIF-2α-HIF-1β interaction, leading to reduced transcription and expression of HIF-2α target genes. In vivo, belzutifan demonstrated anti-tumor activity in mouse xenograft models of renal cell carcinoma.

2 DOSAGE AND ADMINISTRATION The recommended dosage of WELIREG in adult patients is 120 mg administered orally once daily with or without food. ( 2.1 ) The recommended dosage of WELIREG in pediatric patients 12 years and older is based on bodyweight: Patients weighing 40 kg or greater: 120 mg orally once daily Patients weighing less than 40 kg: 80 mg orally once daily 2.1 Recommended Dosage The recommended dosages for WELIREG are listed in Table 1. Table 1: Recommended Dosage Indication Recommended WELIREG Dosage Duration of Therapy von Hippel-Lindau Disease 120 mg orally once daily. Until disease progression or unacceptable toxicity. Adjuvant Treatment of ccRCC 120 mg orally once daily in combination with pembrolizumab or pembrolizumab and berahyaluronidase alfa-pmph. For the recommended dosage of pembrolizumab or pembrolizumab and berahyaluronidase alfa-pmph, refer to the respective Prescribing Information. Until disease recurrence or unacceptable toxicity, or up to 54 weeks. Treatment of Advanced ccRCC 120 mg orally once daily. Until disease progression or unacceptable toxicity. Pheochromocytoma or Paraganglioma Adults: 120 mg orally once daily. Pediatric patients 12 years and older based on bodyweight: Patients weighing 40 kg or greater: 120 mg orally once daily. Patients weighing less than 40 kg: 80 mg orally once daily. Until disease progression or unacceptable toxicity. Administration Instructions WELIREG should be taken at the same time each day and may be taken with or without food. Advise patients to swallow tablets whole. Do not chew, crush, or split WELIREG prior to swallowing. If a dose of WELIREG is missed, it can be taken as soon as possible on the same day. Resume the regular daily dose schedule for WELIREG the next day. Do not take extra tablets to make up for the missed dose. If vomiting occurs any time after taking WELIREG, do not retake the dose. Take the next dose on the next day. 2.2 Dosage Modifications for Adverse Reactions Dosage modifications for WELIREG for adverse reactions are summarized in Table 2 . The recommended dose reductions are: First dose reduction: WELIREG 80 mg orally once daily Second dose reduction: WELIREG 40 mg orally once daily Third dose reduction: Permanently discontinue Table 2: Recommended Dosage Modifications for Adverse Reactions Adverse Reaction Severity Dosage Modification Anemia [see Warnings and Precautions (5.1) ] Adjuvant ccRCC Indication: Hemoglobin <9 g/dL or transfusion indicated Withhold WELIREG until hemoglobin ≥9 g/dL. Resume WELIREG at the same or reduced dose; or discontinue depending on the severity of anemia. Life-threatening or urgent intervention indicated Withhold WELIREG until hemoglobin ≥9 g/dL. Resume WELIREG at a reduced dose once resolved, or permanently discontinue. All Other Indications: Hemoglobin <8 g/dL or transfusion indicated Withhold WELIREG until hemoglobin ≥8 g/dL. Resume WELIREG at the same or reduced dose; or discontinue depending on the severity of anemia. Life-threatening or urgent intervention indicated Withhold WELIREG until hemoglobin ≥8g/dL. Resume WELIREG at a reduced dose once resolved, or permanently discontinue. Hypoxia [see Warnings and Precautions (5.2) ] Decreased oxygen saturation with exercise (e.g., pulse oximeter <88%) Consider withholding WELIREG until resolved. Resume WELIREG at the same dose or at a reduced dose depending on the severity of hypoxia. Decreased oxygen saturation at rest (e.g., pulse oximeter <88% or PaO 2 ≤55 mm Hg) or urgent intervention indicated Life-threatening or recurrent symptomatic hypoxia Withhold WELIREG until resolved. Resume WELIREG at reduced dose or discontinue depending on the severity of hypoxia. Permanently discontinue WELIREG. Other Adverse Reactions [see Adverse Reactions (6) ] Grade 3 Withhold WELIREG until resolved to ≤ Grade 2. Consider resuming WELIREG at a reduced dose (reduce by 40 mg). Permanently discontinue WELIREG upon recurrence of Grade 3. Grade 4 Permanently discontinue WELIRE

6 ADVERSE REACTIONS The following clinically significant adverse reactions are discussed elsewhere in the labeling: Anemia [see Warnings and Precautions (5.1) ] Hypoxia [see Warnings and Precautions (5.2) ] VHL disease : Most common (≥25%) adverse reactions, including laboratory abnormalities, were decreased hemoglobin, fatigue, increased creatinine, headache, dizziness, increased glucose, and nausea. ( 6.1 ) ccRCC : Most common (≥25%) adverse reactions for WELIREG, including laboratory abnormalities, in combination with pembrolizumab were decreased hemoglobin, increased alanine aminotransferase (ALT), fatigue, increased aspartate aminotransferase (AST), decreased lymphocytes, and increased alkaline phosphatase. ( 6.1 ) Most common (≥25%) adverse reactions for WELIREG as monotherapy, including laboratory abnormalities were decreased hemoglobin, fatigue, musculoskeletal pain, increased creatinine, decreased lymphocytes, increased ALT, decreased sodium, increased potassium, and increased AST. ( 6.1 ) PPGL : Most common (≥25%) adverse reactions, including laboratory abnormalities were anemia, fatigue, musculoskeletal pain, decreased lymphocytes, increased ALT, increased AST, increased calcium, dyspnea, increased potassium, decreased leukocytes, headache, increased alkaline phosphatase, dizziness, and nausea. ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact Merck Sharp & Dohme LLC at 1-877-888-4231 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch . 6.1 Clinical Trials Experience Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice. von Hippel-Lindau (VHL) disease LITESPARK-004 The safety of WELIREG was evaluated in an open-label clinical trial (LITESPARK-004) in 61 patients with VHL disease who had at least one measurable solid tumor localized to the kidney [see Clinical Studies (14.1) ] . Patients received WELIREG 120 mg orally once daily until disease progression or unacceptable toxicity. The median duration of exposure to WELIREG was 68 weeks (range: 8.4 to 104.7 weeks). Serious adverse reactions occurred in 15% of patients who received WELIREG, including anemia, hypoxia, anaphylaxis reaction, retinal detachment, and central retinal vein occlusion (1 patient each). Permanent discontinuation of WELIREG due to adverse reactions occurred in 3.3% of patients. Adverse reactions which resulted in permanent discontinuation of WELIREG were dizziness and opioid overdose (1.6% each). Dosage interruptions of WELIREG due to an adverse reaction occurred in 39% of patients. Adverse reactions which required dosage interruption in >2% of patients were fatigue, decreased hemoglobin, anemia, nausea, abdominal pain, headache, and influenza-like illness. Dose reductions of WELIREG due to an adverse reaction occurred in 13% of patients. The most frequently reported adverse reaction which required dose reduction was fatigue (7%). The most common (≥25%) adverse reactions, including laboratory abnormalities, that occurred in patients who received WELIREG were decreased hemoglobin, fatigue, increased creatinine, headache, dizziness, increased glucose, and nausea. Table 3 summarizes the adverse reactions reported in patients treated with WELIREG in LITESPARK-004. Table 3: Adverse Reactions Occurring in ≥10% of Patients Who Received WELIREG in LITESPARK-004 Adverse Reaction WELIREG (n=61) All Grades Graded per NCI CTCAE v4.0 (%) Grade 3-4 (%) General Fatigue Includes other related terms 64 5 Nervous system Headache 39 0 Dizziness 38 0 Gastrointestinal Nausea 31 0 Constipation 13 0 Abdominal pain 13 0 Eye Disorders Visual impairment Includes visual impairment, vision blurred, central retinal vein occlusion and retinal detachment 21 3.3 Infections Upper respiratory tract infection 21 0 Respiratory, Thoracic and Mediastinal Dyspnea 20 1.6 Muscul

5 WARNINGS AND PRECAUTIONS Anemia : Monitor for anemia before initiation of and periodically throughout treatment with WELIREG. Withhold, reduce dose, or permanently discontinue WELIREG based on severity. ( 2.2 , 5.1 ) Hypoxia : Monitor oxygen saturation before initiation of, and periodically throughout, treatment with WELIREG. For hypoxia at rest, withhold until resolved, resume at reduced dose, or discontinue depending on severity. For life-threatening hypoxia, permanently discontinue WELIREG. ( 2.2 , 5.2 ) 5.1 Anemia WELIREG can cause severe anemia that can require blood transfusion. Monitor for anemia before initiation of, and periodically throughout, treatment with WELIREG. Transfuse patients as clinically indicated. Withhold, reduce dose, or permanently discontinue WELIREG based on severity [see Dosage and Administration (2.2) ] . von Hippel-Lindau (VHL) disease In LITESPARK-004, decreased hemoglobin occurred in 93% of patients and 7% had Grade 3 events [see Adverse Reactions (6.1) ] . Median time to onset of anemia was 31 days (range: 1 day to 8.4 months). The safety of erythropoiesis stimulating agents (ESAs) for treatment of anemia in patients with VHL disease treated with WELIREG has not been established. Randomized controlled trials in patients with cancer receiving myelosuppressive chemotherapy with ESAs have shown that ESAs increased the risks of death and serious cardiovascular reactions, and decreased progression-free survival and/or overall survival. See the prescribing information for ESAs for more information. Renal Cell Carcinoma with a Clear Cell Component (ccRCC) In LITESPARK-005, decreased hemoglobin occurred in 88% of patients and 29% had Grade 3 events [see Adverse Reactions (6.1) ] . Median time to onset of anemia was 29 days (range: 1 day to 16.6 months). Of the patients with anemia, 22% received transfusions only, 20% of patients received ESAs only and 12% received both transfusion and ESAs. In LITESPARK-022, decreased hemoglobin occurred in 95% of patients and 11% had Grade 3 or higher events [see Adverse Reactions (6.1) ]. Median time to onset of anemia was 42 days (range: 1 day to 11.1 months). Of the patients with anemia, 5% received transfusions only, 8% received ESAs only, and 1.3% received both transfusion and ESAs. Pheochromocytoma or Paraganglioma (PPGL) In LITESPARK-015, anemia occurred in 96% of patients and 22% had Grade 3 events [see Adverse Reactions (6.1) ] . Median time to onset of anemia was 29 days (range: 1 day to 22.1 months). Of the patients with anemia, 20% received transfusions only, 26% received ESAs only, and 6% received both transfusion and ESAs. 5.2 Hypoxia WELIREG can cause severe hypoxia that may require discontinuation, supplemental oxygen, or hospitalization [see Dosage and Administration (2.2) ]. Monitor oxygen saturation before initiation of, and periodically throughout, treatment with WELIREG. For decreased oxygen saturation with exercise (e.g., pulse oximeter <88% or P a O 2 ≤55 mm Hg), consider withholding WELIREG until pulse oximetry with exercise is greater than 88%, then resume at the same dose or at a reduced dose. For decreased oxygen saturation at rest (e.g., pulse oximeter <88% or PaO2 ≤55 mm Hg) or urgent intervention indicated, withhold WELIREG until resolved and resume at a reduced dose or discontinue. For life-threatening hypoxia or for recurrent symptomatic hypoxia, permanently discontinue WELIREG [see Dosage and Administration (2.2) ] . Advise patients to report signs and symptoms of hypoxia immediately to a healthcare provider. von Hippel-Lindau (VHL) disease In LITESPARK-004, hypoxia occurred in 1.6% of patients [see Adverse Reactions (6.1) ] . Renal Cell Carcinoma with a Clear Cell Component (ccRCC) In LITESPARK-005, hypoxia occurred in 15% of patients and 10% had Grade 3 events [see Adverse Reactions (6.1) ] . Of the patients with hypoxia, 69% were treated with oxygen therapy. Median time to onset of hypoxia was 30.5 days (range: 1 day to 21.1 mont

4 CONTRAINDICATIONS None. None. ( 4 )

10 OVERDOSAGE There is no specific treatment for WELIREG overdose. In cases of suspected overdose, withhold WELIREG 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).