NEW YORK – The European Commission (EC) on Tuesday granted conditional marketing authorization to Merck's HIF-2α inhibitor Welireg (belzutifan) for some von Hippel-Lindau (VHL) disease-associated cancers.
The approval includes patients with VHL-associated localized renal cell carcinoma, central nervous system (CNS) hemangioblastomas, or pancreatic neuroendocrine tumors for whom localized procedures are unsuitable. The EC also granted conditional approval to Welireg for an all-comer population of previously treated advanced clear cell renal cell carcinoma.
The approval in VHL-associated cancers was based on results from the Phase II LITESPARK-004 trial. In the study, treatment with Welireg led to responses in 49 percent of renal cell carcinoma patients, 63 percent of CNS hemangioblastomas, and 83 percent of pancreatic neuroendocrine tumors. Some patients in the study also experienced a complete response on Welireg, including 17 percent of pancreatic neuroendocrine tumor and 4 percent of CNS hemangioblastoma patients.
"The approval of Welireg in the EU introduces the first and only systemic treatment option for adult patients with certain VHL disease-associated tumors for whom localized procedures are unsuitable," Marjorie Green, senior VP and head of oncology global clinical development at Merck Research Laboratories, said in a statement. "This is an important moment, and we are pleased that Welireg, a first-in-class HIF-2α inhibitor, can now potentially help these patients in need."
The EC's conditional approval will be valid for one year and subject to annual renewal pending additional data from the LITESPARK-004 trial and another Phase II trial of Welireg in patients with VHL-associated tumors.
Welireg was approved in the US for the same indication in VHL-associated tumors in 2021.