Clinical Trials

Merck’s phase 3 LITESPARK-005 trial of Welireg met primary endpoint

Merck (known as MSD outside of the US and Canada) has shared topline results from its phase 3 LITESPARK-005 trial, assessing Welireg (belzutifan) for the treatment of adult patients with advanced renal cell carcinoma (RCC) that has progressed following PD-1/L1 checkpoint inhibitor and vascular endothelial growth factor-tyrosine kinase inhibitor (VEGF-TKI) therapies.
Throughout the trial, Welireg showed a statistically significant and clinically meaningful improvement in progression-free survival (PFS) compared to everolimus. There was also a statistically significant improvement in objective response rate (ORR), the trial’s secondary endpoint.
In addition, there was a trend towards an improvement in overall survival (OS), however this didnotreachstatisticalsignificance.Itisexpectedthat OS will be further assessed in subsequent analyses. The safety profile of the drug was consistent with previous studies.
Dr Marjorie Green, senior vice president and head of late-stage oncology, global clinical development at Merck Research Laboratories, commented: “Patients with advanced RCC face low survival rates, and for those whose cancer progresses following PD-1/L1 and VEGF-TKI therapies, there is a need for new treatment options that can reduce their risk of disease progression or death. This is the first phase 3 trial to show positive results in advanced RCC following these therapies and the first new mechanism to demonstrate potential in advanced RCC in recent years. We look forward to discussing these results with health authorities.”
Full results of the study are expected to be presented at an upcoming medical meeting and will then be shared with the relevant regulatory authorities.