Originally developed to prevent osteoporosis, lassaxifen is a selective estrogen receptor modulator. In other words, lassaxifen has both estrogen and anti-estrogen effects in different tissues, which is mainly mediated by the estrogen receptors.
Previous observational studies have found that compared with other drugs, lasofoxifene can effectively prevent breast cancer, reduce the incidence rate of ER-positive breast cancer by 80 percent , in addition to inhibiting bone loss.
In addition, lassaxifen has good safety, can maintain bone mineral density, prevent vaginal dryness and do not stimulate the uterus.
But at present, although scientists have found that it is helpful to prevent breast cancer, it is not clear whether it has anti-tumor effect.
In this new study, researchers in Chicago carried out experiments in mice, all of which had ER positive breast cancer, and all of them had ER mutations.
The researchers treated some mice with lassaxifen and others with fulvestan.
In addition, they also tested the two drugs in combination with paboxib.
Paboxib is a commonly used chemotherapeutic drug. It can prevent cancer cells from proliferating.
In the experiment, the researchers found that rasoxifen alone was more effective than fulvestan in preventing tumor growth and reducing cancer cell metastasis.
However, the combination of the two drugs can improve the efficacy of the two drugs.
This study shows that raloxifene is better than breast cancer in treating breast cancer, whether used alone or in combination with the use of the same method.
In addition to fewer side effects, lasoxifen has other significant advantages.
Unlike fulvestan, which must be injected, lassaxifen can be taken orally.
It also has a long half-life, which means that lasoxifen will stay in the body longer.
Clinically, the desired effect is that whenever a new estrogen receptor is produced or the receptor is mutated, the drugs in the patient can inhibit it.
The advantage of lasoxifen is that it works longer.
The University of Chicago is conducting a phase II clinical trial. They used raloxifene as a treatment for menopausal women who received second-line treatment. These women had ER positive breast cancer, metastasis, and ER mutation.
Follow up researchers will also continue to study the combination of lassaxifen and abecilin, a chemotherapeutic drug similar to pabocillin.
At present, most ER positive metastatic breast cancer women are treated with vitamin.
But according to the study, fulvestan is not the best drug. For female patients, the applicability of lassaxifen is better than that of fulvestan.