Merck's HIF-2α Inhibitor Welireg® (Belzutifan) Officially Launched Commercially in China

Shanghai, China,2025Year5Month22Day——MSD (MSD is the corporate name of Merck & Co., Inc. in Rahway, New Jersey, U.S.) announced its hypoxia-inducible factor 2α (HIF-2α) inhibitor Belzutifan (trade name: Welirey).^®) has been officially commercially launched in China, applicable to adult patients with Von Hippel-Lindau (VHL) disease-associated renal cell carcinoma (RCC), central nervous system (CNS) hemangioblastoma, or pancreatic neuroendocrine tumors (pNET) who do not require immediate surgical treatment.

      VHL disease is a rare autosomal dominant genetic disorder.^[1], caused by mutations in the VHL tumor suppressor gene located on chromosome 3p25-26.^[1],[2]VHL disease is often characterized by a multi-organ tumor syndrome, such as central nervous system hemangioblastomas, retinal hemangioblastomas, renal cell carcinoma, pancreatic tumors, etc.^[1],[3]Among them, central nervous system hemangioblastoma and renal cell carcinoma are the main causes of death in patients.^[1]The average life expectancy of VHL patients in China is only 62 years.^[4]。

      "VHL disease, as a hereditary and rare disease, is difficult to cure completely. Surgical resection of VHL-related tumors is one of the main treatment options, but patients often experience tumor recurrence after surgery and may face multiple surgeries throughout their lifetime."^[1]", urgently awaiting new treatment options to improve patient survival and quality of life."Bezutifan Clinical Trial Principal Investigator (PI), Institute of Urology, Peking University First HospitalStanding CommitteeProfessor Gong Kan, Deputy Director"HIF-2α is the main driver of tumorigenesis in VHL-associated tumors."^[5],[6],[7], while the discovery of hypoxia-inducible factor (HIF) and the mechanism of cellular oxygen sensing and adaptation won the 2019 Nobel Prize in Physiology or Medicine.^[8]Belzutifan tablets, as an HIF-2α inhibitor, can block the interaction between HIF-2α and hypoxia-inducible factor 1β (HIF-1β), leading to a reduction in the transcription and expression of HIF-2α target genes.^[9], thereby inhibiting tumor growth. Thanks to the national attention to rare diseases and the introduction of a series of favorable policies, Belzutifan has been approved for the clinical treatment of VHL disease. This marks a new chapter in the treatment of VHL disease in China and will bring new options for Chinese patients with VHL disease."

Anna Tian, Senior Vice President of MSD Global and President of MSD ChinaRepresents: "Vilari^®(Belzutifan Tablets) as the first and only HIF-2α inhibitor currently approved in China^[10], will bring new treatment options for adult patients with VHL-associated renal cell carcinoma (RCC), central nervous system (CNS) hemangioblastomas, or pancreatic neuroendocrine tumors (pNET). MSD is always committed to transforming cutting-edge academic achievements and breakthrough results into treatment solutions that benefit patients, providing them with more treatment choices. In the field of rare diseases, especially rare tumors, there are still many unmet treatment needs. Verily.^®(The launch of Bezuftinib tablets) represents MSD's solemn commitment to this field. Relying on its leading position and profound accumulation in the field of oncology research and innovation, MSD will continue to adhere to bringing cutting-edge treatment options to healthcare professionals and patients, jointly building a healthy future."

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      At MSD (the corporate name of Merck & Co., Inc. in the United States, located in Rahway, New Jersey), we work together to pursue a shared goal: harnessing the power of cutting-edge science to save lives and improve health worldwide. For over 130 years, we have brought hope to humanity by developing critical medicines and vaccines. We are committed to being a leading research-intensive biopharmaceutical company—today, we stand at the forefront of innovation, delivering transformative solutions to advance the prevention and treatment of diseases in humans and animals. We have built a diverse and inclusive global workforce, operating responsibly every day to ensure a safe, sustainable, and healthy future for all people and communities. For more information, visit www.msd.com and follow us on X (formerly Twitter), LinkedIn, and YouTube.

About MSD China

      China is a crucial part of MSD's global growth strategy. MSD’s China headquarters is located in Shanghai, with a research and development center in Beijing and manufacturing facilities in Hangzhou, Ningbo, and Tianjin, integrating R&D, manufacturing, and commercial operations. We are fully committed to providing high-quality innovative medicines, vaccines, and services to the people of China, benefiting Chinese society. For more information, please visit MSD China's official website or follow MSD China's official social media account on WeChat.

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[3] Maher ER, lselius L, Yates JR, et al. Von Hippel-Lindau disease : a genetic study[J].J Med Genet, 1991,28(7): 443-447.

[4] Wang JY, Peng SH,liT, et al. Risk factors for survival inpatients with von Hippel-Lindau disease[ J]. Journal of Medical Genetics,2018,55(5):322-328.

[5] Shepherd STC, Drake WM, Turajlic S. The road to systemic therapy in von Hippel-Lindau (VHL) disease: Are we there yet?[J].Eur J Cancer. 2023;182:15-22.

[6] William Y Kim , Michal Safran, Marshall R M Buckley,et al.Failure to prolyl hydroxylate hypoxia-inducible factor alpha phenocopies VHL inactivation in vivo[J]. EMBO J. 2006 Oct 4;25(19):4650-4662.

[7] Chuan Shen , Rameen Beroukhim, Steven E Schumacher,et al. Genetic and functional studies implicate HIF1α as a 14q kidney cancer suppressor gene[J]. Cancer Discov. 2011 Aug;1(3):222-235.

[8] Nanduri R Prabhakar. 2019 Nobel Prize in Physiology or Medicine[J]. Physiology (Bethesda). 2020 Mar 1;35(2):81-83.

[9]Bezutifan Chinese Instructions, 2024 Edition, MSD

[10]As of May 20, 2025.