Two generic drugs can help cut the rate of breast cancer deaths in postmenopausal women, according to two studies published in the Lancet journal. The researchers also said that these drugs -- aromatase inhibitors and bisphosphonates -- can be used together to enhance their benefits and reduce certain side effects.

Aromatase inhibitors (AIs) are hormone-suppressing drugs prescribed to women with postmenopausal breast and ovarian cancer, while bisphosphonates are used to treat osteoporosis. 

The results of the two studies were announced by the Early Breast Cancer Trialists' Collaborative Group, a worldwide collaboration formed by the University of Oxford in England to collect the findings of randomized trials of early breast cancer treatment.

The first study conducted by the Institute of Cancer Research, UK, and the Royal Marsden NHS Foundation Trust in England analyzed data from 30,000 post-menopausal women who participated in nine randomized trials.

The findings showed that intake of AIs for five years reduced the risk of the cancer recurring by about a third, and the risk of dying from breast cancer by about 15 percent through the decade after the start of the treatment. The researchers stated that mortality rates associated with breast cancer would reduce by 40 percent over 10 years after beginning the treatment.

The second study, also conducted by the Institute of Cancer Research, found that bisphosphonates increased chances of survival among breast cancer patients if taken for two years to five years after the onset of the disease. For the study, researchers combined data from 18,766 women from 26 clinical trials. The study team stated that as breast cancer mostly spreads to the bone, following a bisphosphonates treatment could result in a 17 percent reduction in the recurrence of cancer.

According to the researchers, among post-menopausal women, bisphosphonate treatment showed an 18 percent decline in breast cancer deaths in the first decade after diagnosis. The researchers, however, noted that bisphosphonate has little effect in premenopausal women.

"These studies provide really good evidence that both of these inexpensive, generic drugs can help to reduce breast cancer mortality in postmenopausal women," Richard Gray, lead statistician for both studies and a professor at Oxford, said, in a press release. 

"The drugs are complementary, because the main side effect of aromatase inhibitors is an increase in bone loss and fractures, while bisphosphonates reduce bone loss and fractures as well as improving survival," Gray noted.