As expected, Pfizer ($PFE) has submitted an early FDA application for palbociclib, beating a quick path to market with a breakthrough breast cancer treatment that could peak at nearly $3 billion a year. The company is betting that palbociclib's Phase II data will be enough to merit a full approval, making its pitch to regulators while the drug's late-stage program remains underway. If Pfizer's gambit works out, the treatment will lead an incoming pack of CDK 4/6 inhibitors that promise to make a meaningful difference for breast cancer patients, trailed by Novartis' ($NVS) LEE011, Eli Lilly's ($LLY) bemaciclib and others. More