China Approves Merck’s WELIREG For Von Hippel Lindau Associated Tumors

Merck, known as MSD outside the U.S. and Canada, announced that China's National Medical Products Administration (NMPA) has approved WELIREG® (belzutifan) for treating adults with Von Hippel-Lindau (VHL) disease. This approval applies to patients requiring therapy for associated renal cell carcinoma (RCC), central nervous system (CNS) hemangioblastomas, or pancreatic neuroendocrine tumours (pNET) without the need for immediate surgery. WELIREG, an oral hypoxia-inducible factor-2 alpha (HIF-2α) inhibitor, is China's first and only approved HIF-2α inhibitor, marking its 17th global approval for this indication.

Dr Marjorie Green, senior vice president and head of oncology, global clinical development, Merck Research Laboratories, said, “This approval of WELIREG brings the first and only systemic therapy to adult patients in China with certain VHL disease-associated tumours who, to date, have not had access to a non-surgical treatment option to help manage manifestations of VHL disease. We are committed to bringing innovative treatment options to patients in need worldwide. We are proud to offer eligible adult patients in China a first-in-class HIF-2α inhibitor as a possible treatment option.”

The approval is based on data from the Phase 2 LITESPARK-004 trial, demonstrating a robust objective response rate (ORR) and median duration of response (DOR). In the trial, WELIREG achieved an ORR of 49% in VHL-associated RCC patients, with responses lasting between 2.8+ and 22.3+ months. Additionally, 56% of responders maintained their response for at least a year.

WELIREG also showed significant efficacy in treating other VHL-associated tumours. Among patients with CNS hemangioblastomas, the ORR was 63%, including a 4% complete response rate, with responses lasting up to 22.3+ months. Similarly, in patients with pNET, WELIREG achieved an ORR of 83%, with 17% achieving complete responses and responses lasting up to 19.4+ months.

Initially approved in the U.S. in August 2021 for VHL-related tumours, WELIREG is also authorised for advanced RCC following prior therapy with a PD-1/PD-L1 inhibitor and a VEGF-TKI. Merck continues to study WELIREG in a broad clinical program, exploring its potential as a monotherapy and in combination treatments for advanced RCC and other cancers.