Cubist Pharmaceuticals Inc. rose after a study of the company's experimental drug for the treatment of complicated urinary tract infections met its goal in a recent Phase III trial of showing that it worked more effectively than an existing antibiotic, called levofloxacin. The treatment, which is known as CXA-201 or ceftolozane/tazobactam, is especially important for Cubist because of its potential to be approved by the FDA to treat several conditions.