Over the 4 years of the osteoporosis treatment trial (involving 7705 patients), EVISTA treatment compared to placebo reduced the risk of total breast cancer by 62% (RR 0.38; CI 0.21, 0.69), the risk of invasive breast cancer by 71% (RR 0.29, CI 0.13, 0.58) and the risk of invasive oestrogen receptor (ER) positive breast cancer by 79% (RR 0.21, CI 0.07, 0.50).