Hutchmed Ltd said on Monday the US Food and Drug Administration has declined to approve its cancer drug, citing the need for a multi-regional clinical trial, becoming the second China-tested drug to be rejected by the US regulator this year.

In its so-called complete response letter to the company, the FDA said current drug data, based on two trials in China and one bridging study in the United States, does not support an approval in the United States at this time.

A multi-regional clinical trial that includes subjects more representative of the US patient population and aligned to current US medical practices is required, the FDA wrote in the letter.

Hutchmed was seeking approval for its drug surufatinib for the treatment of pancreatic and extra-pancreatic neuroendocrine tumors, a condition that has a few treatment options.

"There are very few treatments approved and used in these rare diseases..We look forward to continued engagement with the FDA on developing a plan to bring surufatinib to patients in the US," Hutchmed CEO Weiguo Su said.

The drug is approved in China for both indications.

The decision is a setback for Hutchmed and raises concerns for some other Chinese drugmakers who have been seeking to bring their products to the US market at lower costs by conducting a single-country clinical trial.

The FDA in March declined to approve Eli Lilly and partner Innovent Biologics Inc's lung cancer drug that had been studied only in China.

It has raised concerns over lack of population diversity in single-country trials, citing the need for conducting studies applicable to the US population.

There are at least 25 applications from China in drug development phases, planned to be submitted or already under review by the FDA, that are predominantly or solely based on trial data from China, the regulator said in February.

Reuters