Dr. Goss said the investigators plan to look for clearer data on how to define which women are high-risk and would benefit from exemestane. They also will be looking for biomarkers that can show how well a woman does while on chemoprevention: something comparable to measures used when patients take anti-hypertensives or cholesterol-lowering drugs.
Another unknown is whether Pfizer, Inc. will seek a chemoprevention indication for exemestane. Aromasin lost patent protection in the United States in Apri, and will lose it in Europe in July, according to company spokesman Christopher Loder. "We cannot comment on our regulatory plans at this time," he said in a hallway interview at the convention center where ASCO is being held.
Loss of exclusivity is likely to mean lower prices for Aromasin, which could make Pfizer less inclined to invest in applications for the indication. Whether insurance companies would pay for chemoprevention use without an indication is also a question – but price might not be a barrier.
Pfizer helped pay for the trial. Dr. Goss and several of his coauthors received honoraria and research funding from Pfizer, as well as other companies. Dr. Davidson and Dr. Kensler disclosed no relevant conflicts of interest.