Mechanism of Action for WELIREG® (belzutifan)
WELIREG works differently by targeting HIF-2α, a key driver of tumor growth1,2
WELIREG is indicated for the treatment of adult patients with advanced renal cell carcinoma with a clear cell component (ccRCC) following an anti–PD-1/L1 and a VEGF-TKI
The approval of WELIREG marks the first treatment option in a novel therapeutic class available for your appropriate adult patients with advanced ccRCC since 20152
Up to 92% of tumors from patients with any ccRCC are characterized by a somatic VHL gene mutation, resulting in the accumulation of HIF-2α.3–6 Approximately one-third of ccRCC may progress to metastatic disease7
HIF-1β = hypoxia-inducible factor 1 beta; HIF-2α = hypoxia-inducible factor 2 alpha; PD-1 = programmed death receptor-1; PD-L1 = programmed death-ligand 1; RCC = renal cell carcinoma; VEGF-TKI = vascular endothelial growth factor tyrosine kinase inhibitor; VHL = von Hippel-Lindau.

References: 1. Targeted drug therapy for kidney cancer. American Cancer Society. Last revised June 25, 2026. https://www.cancer.org/cancer/kidney-cancer/treating/targeted-therapy.html. Accessed August 3, 2026. 2. Choi SH, Chen Y-W, Panian J, Yuen K, McKay RR. Emerging innovative treatment strategies for advanced clear cell renal cell carcinoma. Oncologist. 2025;30(3):oyae276. 3. Correa AF, Rini BI, Linehan WM, Schmidt LS, Lane BR, Uzzo RG. Cancer of the kidney. In: DeVita VT Jr, Lawrence TS, Rosenberg SA, eds. Cancer: Principles and Practice of Oncology. 12th ed. Wolters Kluwer; 2022:729–755. 4. Kaelin WG Jr. HIF2 inhibitor joins the kidney cancer armamentarium. J Clin Oncol. 2018;36(9):908–910. 5. Kaelin WG Jr. The VHL tumor suppressor gene: insights into oxygen sensing and cancer. Trans Am Clin Climatol Assoc. 2017;128:298–307. 6. Choi WSW, Boland J, Lin J. Hypoxia-inducible factor-2α as a novel target in renal cell carcinoma. J Kidney Cancer VHL. 2021;8(2):1–7. 7. Mattila KE, Vainio P, Jaakkola PM. Prognostic factors for localized clear cell renal cell carcinoma and their application in adjuvant therapy. Cancers. 2022;14(1):239.