Pfizer Inc. said it ended an advanced trial of its experimental lung cancer drug figitumumab after an independent safety committee determined the treatment was unlikely to improve patients’ survival.

The study, for use of figitumumab in patients with lung cancer, stopped enrolling patients in September after the committee found an “apparent imbalance” between the number of deaths and other complications among patients taking the medicine and those in control groups, the New York-based company said today in a statement.