Eli Lilly''s drug Evista, used for the treatment of osteoporosis, significantly reduces the incidence of breast cancer in post-menopausal women, says new data published in the 16 June edition of the Journal of the American Medical Association.

According to the authors of the study, the data indicate that Evista reduced the risk of newly diagnosed invasive breast cancer by 76 per cent during a median of 40 months of treating post-menopausal women for osteoporosis. The data was collected from a study involving 7,705 women. It was funded by Eli Lilly but involved external researchers who for the first time confirmed Evista''s role in cancer prevention.

Expected to be a blockbuster drug, Evista managed sales of only $144 million in 1998, its first year. The drug faced stiff competition from Merck''s drug Fasomax, believed to be more potent, and struggled to make an impact in a new and undeveloped osteoporosis drug market.

Osteoporosis is an ailment affecting post-menopausal women. The onset of the disease is usually between the age of 45-55 years and is characterised by rapid de-mineralisation of bones making them prone to fractures. It is estimated that one out of every two women in the world is at a risk of developing osteoporosis.

In spite of such a vast potential, the market for osteoporosis remains small, because of the incidence of breast cancer associated with the hormonal replacement therapy, or HRT, a popular remedy to delay the onset of the disease.

Analyst believes that though the study would not change perception of the drug in cancer prevention immediately, it would eventually open a wide market for the drug. Analysts feel that the Food and Drug Administration, a "very cautious" body that regulates drugs in US, may not allow Eli Lilly to market the drug for prevention of breast cancer until long term studies are available in several years.