Merck-Eisai’s kidney cancer drug combo fail to improve survival in late-stage trial

April 21 (Reuters) – Merck and Eisai’s experimental combination treatments failed to significantly improve survival or reduce the risk of cancer progression or death in patients with the most common form of kidney cancer in a late-stage trial.

The companies said on Tuesday they tested Merck’s Keytruda and Eisai’s Lenvima, a combination already approved in the U.S., with Merck’s Welireg as a first-line treatment for patients with clear cell renal cell carcinoma, which makes up about 80% of all kidney cancer cases.

The study, which enrolled 1,688 patients, also tested the combination of Lenvima and MK-1308A, the co-formulation of Merck’s blockbuster drug, Keytruda, and its experimental antibody quavonlimab.

An interim analysis showed that neither combinations generated better results compared to the treatment with a combination of Keytruda and Lenvima, thereby failing to meet the two main goals of the study.

Overall survival, which measures the length of time patients live after diagnosis or the start of treatment, is a key indicator of how well a treatment works.

The data derails a near-term path to first-line approval for Merck’s Welireg, Cantor analyst Carter Gould said, adding that it challenges the drug’s potential to reach more than $2 billion in peak sales.

Gould projects Welireg sales of $1 billion in 2026, peaking at $2 billion in 2035.

The drug generated $716 million in sales last year.

The safety profile of the new combinations under trial were consistent with the previous studies, the companies said, adding that they are conducting a full evaluation of the data.

The Keytruda-Lenvima combination therapy is approved in the U.S., the European Union, Japan and other countries as a first-line treatment for adult patients with advanced renal cell carcinoma.

(Reporting by Mariam Sunny in Bengaluru; Editing by Shilpi Majumdar and Shinjini Ganguli)