EC Approves Merck’s Welireg for Von Hippel-Lindau Disease and Kidney Cancer

Merck & Co, operating as MSD outside the US and Canada, has received conditional approval from the European Commission (EC) for its drug Welireg (belzutifan). This medication has been authorized as a standalone treatment for specific patients suffering from von Hippel-Lindau (VHL) disease and renal cell carcinoma (RCC). The EC's decision marks a significant advancement in the treatment options available for individuals facing these challenging conditions.

Welireg is now approved for adult patients diagnosed with VHL disease who cannot undergo localized treatments for associated localized renal cell carcinoma, central nervous system hemangioblastomas, or pancreatic neuroendocrine tumors. Additionally, the drug is sanctioned for adults with advanced clear cell RCC that has progressed after at least two prior therapeutic regimens that incorporated a programmed death receptor-1 (PD-1) or programmed death-ligand 1 (PD-L1) inhibitor, along with two or more vascular endothelial growth factor (VEGF) targeted therapies. This approval provides a new avenue for patients who have exhausted other treatment options, offering hope for improved management of their conditions.

VHL disease affects approximately 15,000 individuals across Europe. It is characterized by a genetic mutation in the VHL gene, leading to abnormal cell growth which can result in cysts or tumors in various organs, such as the kidneys and pancreas. These growths may impair organ function and potentially become cancerous. In contrast, RCC is far more prevalent, with over 130,000 new cases identified in Europe in 2020 alone. The disease is more common in men, and about 30% of patients are diagnosed at an advanced stage, highlighting the need for effective treatments like Welireg.

Merck's acquisition of Welireg occurred in 2019 when the company purchased Peloton Therapeutics for $1.1 billion. The drug, administered orally, is designed to inhibit hypoxia-inducible factor 2 alpha (HIF-2α), a transcription factor that plays a crucial role in regulating cellular proliferation, angiogenesis, and tumor growth. By targeting HIF-2α, Welireg aims to disrupt these processes and slow down or stop the progression of tumors.

The EC's approval of Welireg for these two indications follows recent recommendations from the European Medicines Agency's human medicines committee. This endorsement was bolstered by promising results from clinical trials, specifically the phase 2 LITESPARK-004 trial for VHL disease and the phase 3 LITESPARK-005 study for RCC. These trials demonstrated the drug's efficacy and potential benefits for patients who have limited treatment options.

Marjorie Green, the senior vice president and head of oncology at Merck Research Laboratories, expressed her satisfaction with the EC's decision. She emphasized the significance of having Welireg available as the first and only systemic treatment option for adult patients with certain VHL disease-associated tumors who cannot undergo localized procedures. She also highlighted its potential as a new option for patients with advanced clear cell RCC that has progressed following treatment with PD-1 or PD-L1 inhibitors and multiple VEGF targeted therapies.

The approval of Welireg marks a pivotal moment for patients suffering from VHL disease and advanced RCC in Europe. As a first-in-class HIF-2α inhibitor, it offers a novel treatment pathway for patients with limited options, potentially improving their quality of life and providing hope in their battle against these challenging conditions.