Pfizer Inc. (PFE), the world’s largest drugmaker, is weighing whether to ask U.S. regulators to expedite their review of a potential $5 billion-a-year treatment to slow a type of incurable breast cancer. The therapy, called PD 0332991, generated excitement among oncologists in December after data showed the drug stopped disease progression for more than two years in 165 patients. That trial was done in the second of three stages of research regularly required for Food and Drug administration approval. The FDA has cleared cancer drugs for sale before final trial results are completed, including New York-based Pfizer’s Xalkori for lung tumors in 2011 and Novartis AG (NOVN)’s Gleevec for leukemia a decade earlier. While no company decision has been made to push for early clearance, “There are some precedents for approval after Phase 2,” said Mikael Dolsten, Pfizer’s head of worldwide research. “We’ll see whether there are ways to accelerate availability of the drug for patients,” Dolsten said in an interview at the JPMorgan Chase & Co. health conference in San Francisco. “We’re obviously open to dialogues and advice from FDA and the European agencies.” Pfizer hopes to start the final-stage trial by the end of March, said Geno Germano, who heads the company’s oncology and specialty care businesses. The medicine is the first in a new class of agents that works by blocking a protein critical in the cancer cell cycle, lead researcher Richard Finn said in December. The study unveiled in December included women with tumors fueled by the hormone estrogen, the most common type of breast cancer. All had metastatic disease, which had spread to other parts of the body and is no longer considered curable. Almost 230,000 women in the U.S. will be diagnosed with breast cancer this year, and more than 39,900 will die from it, according to the American Cancer Society.
