UPDATE 1-Threshold's lung cancer study does not meet goal

(Adds details, share movement)

Oct 11 (Reuters) - Threshold Pharmaceuticals Inc (THLD.O) said a mid-stage study of its experimental drug glufosfamide to treat small cell lung cancer did not meet the main goal of objective response rate and that it will stop further enrollment in the trial.

The clinical trial used a two-stage design to ensure an adequate response rate to justify complete enrollment and only one confirmed partial response was observed among the 21 patients enrolled in the first stage.

The low response rate indicates that glufosfamide is not sufficiently effective as a single agent for patients with small cell lung cancer, the company said in a statement.

However, patients currently enrolled in the clinical trial will be given the option to continue in the trial, the company added.

Threshold's shares fell more than 18 percent in late electronic trade, after closing at 87 cents Thursday on the Nasdaq. (Reporting by Jennifer Robin Raj in Bangalore)