Manufactured by Pfizer, the bone drug, Fablyn, has been found to reduce the risk of breast cancer and bone fracture in post-menopausal women with osteoporosis. Unable to be approved as an osteoporosis treatment by the Food and Drug Administration (FDA) last year, Pfizer is "exploring strategic options" that include licensing out Fablyn or selling the rights Pfizer now holds, in line with plans disclosed last year, Victoria Davis, a spokeswoman, said in an e-mail yesterday.

Also known as lasofoxifene, Fablyn is a non-steroidal selective estrogen receptor modulator (SERM). These types of drugs work by blocking the effects of estrogen in the breast tissue. If a SERM is in the estrogen receptor, there is no room for estrogen and it can't attach to the cell. If estrogen isn't attached to a breast cell, the cell doesn't receive estrogen's signals to grow and multiply.

According to a study published in the Journal of the National Cancer Institute, women taking the medicine had a 79% lower chance of breast cancer compared with those on placebo. When the drug went up for approval previously, it was found to cause blood clots, leg cramps, and hot flushes. Physicians are now saying that the benefits far outweigh the risk.  Bloomberg states that "for the new report, the authors looked at a previous study of 8,556 postmenopausal women, ages 59 to 80, who had low bone density. They were randomly assigned to receive 0.5 milligrams of Fablyn or else 0.25 milligrams of Fablyn or a placebo, and followed for five years.  During that time, 49 women developed breast cancer, including five in the 0.5 milligram Fablyn group and 24 in the placebo group, according to the research published today."