A large study of Bristol-Myers Squibb Co's Opdivo treatment has been halted after proving the drug is effective against the most common form of lung cancer, the company said, positioning the medicine for far wider use than its already approved lung cancer and melanoma indications. The U.S. drugmaker on Friday said the study, called Checkmate-057, was stopped early after an independent data monitoring committee concluded that Opdivo provided a survival advantage over docetaxel, a standard chemotherapy, among patients with previously treated non-squamous non-small cell lung cancer .