Pfizer (NYSE:PFE) announced today a successful phase 2 trial of its breast cancer drug Palbociclib, which had shares up 2.5% on the news. "We are delighted with the final data, which suggests the potential for Palbociclib to transform the standard of care," Pfizer announced. The company could file for accelerated approval in March, which would potentially mean approval this year.

In this video, Motley Fool health-care analyst David Williamson looks at the competition in this space, the potential market for Pfizer's new drug, and one secret winner that stands to benefit here.

David Williamson owns shares of Novartis and Pfizer. The Motley Fool has no position in any of the stocks mentioned. Try any of our Foolish newsletter services free for 30 days. We Fools don't all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.