Oct 29 (Reuters) - Merck ( MRK ) and Japan's Eisai ( ESALF )

said on Wednesday they will shut down a late-stage

study testing an experimental combination therapy to treat a

type of liver cancer, after interim results showed the treatment

was unlikely to improve overall survival.

The study tested Merck's ( MRK ) blockbuster drug Keytruda and

Eisai's ( ESALF ) Lenvima, along with a liver cancer procedure called

transarterial chemoembolization (TACE), in patients with

unresectable, non-metastatic hepatocellular carcinoma, which is

the most common type of liver cancer.

This type of cancer is often diagnosed at an intermediate

stage, where curative treatments such as resection, ablation or

transplant are not viable. However, some patients may still be

able to get treatments like TACE, which target the liver

directly.

In an interim analysis, patients treated with the

combination lived longer without their cancer getting worse,

meeting one of the trial's goals for progression-free survival

compared to TACE.

But the interim data showed the combination was unlikely to

meet the overall survival goal, prompting the companies to end

the trial early.

The combination therapy had previously failed in trials

studying it for other types of cancers such as lung, esophageal

cancer and skin, among others.

The results do not affect the current approved indications

or other ongoing trials.

The Keytruda-Lenvima combination therapy is approved in the

U.S., the European Union, Japan and other countries for the

treatment of a type of kidney cancer, and a type of uterine

cancer.