June 11 (Reuters) - Eli Lilly and Co's recently approved stomach cancer drug Cyramza failed to prolong the lives of patients with advanced liver cancer in a late-stage trial, the drugmaker said on Wednesday.

Patients enrolled in the trial previously had failed to benefit from standard chemotherapy for liver cancer.

"Liver cancer is a very difficult-to-treat tumor type and no Phase III study has been able to demonstrate improved survival in the second-line setting," Lilly said in a release.

Cyramza also failed in an earlier study to improve outcomes for patients with breast cancer.

But the drug has proven effective in a late-stage trial against the most common form of lung cancer, and Lilly is also testing it against colorectal cancer.

Investment bank Cowen and Co has predicted Cyramza will generate annual sales of $1.2 billion by 2020, assuming it is approved for at least one additional type of cancer, beyond stomach cancer.

Lilly shares slipped 1.2 percent in premarket trading, from their closing price Tuesday of $59.75 on the New York Stock Exchange.

(Reporting by Ransdell Pierson; Editing by Chizu Nomiyama)