Federal regulators on Friday approved an Ariad Pharmaceuticals Inc. drug to treat two types of leukemia, giving the Cambridge company the green light more than three months ahead of schedule to sell the medicine in the United States.

The once-daily pill, known by its chemical name of ponatinib during years of research and clinical trials, will be marketed under the brand name Iclusig, the biotechnology company said. It was approved to treat chronic myeloid leukemia, as well as Philadelphia chromosome positive acute lymphoblastic leukemia, for patients who can’t tolerate or have developed a resistance to existing therapies.