Pfizer breast cancer drug succeeds in mid-stage trial

Pfizer Inc's experimental breast cancer drug significantly delayed progression of symptoms in a mid-stage trial, meeting the study's primary goal and keeping Pfizer in the forefront of a race for a new standard of care for the disease. Pfizer shares were up nearly 4 percent on positive findings for the oral treatment, called palbociclib, one of the company's most important experimental drugs that some analysts believe could eventually claim annual sales of more than $5 billion, if approved. The trial tested the pill in post-menopausal patients with locally advanced or newly diagnosed breast cancer that had spread to other parts of the body. "We are delighted with the final data," Pfizer said in a release, adding the company will discuss the successful data on progression-free survival with the U.S. Food and Drug Administration "to determine next steps" for palbociclib.