Inhaled hormone treatment offer breast cancer alternative

An inhaled hormone treatment may offer women at high risk of breast cancer an alternative to losing their breasts or ovaries, researchers say.

The nasal spray contains a drug that effectively shuts down the ovaries, and a small amount of hormones that keep the patient from going into premature menopause, the researchers told a breast cancer conference in San Antonio, Texas.

A very early trial involving just 13 women suggests the treatment may at least make it easier for doctors to watch for breast cancer in high-risk patients, and offers some hope it could help to prevent cancer, the researcher said.

“This is a regimen that preserves a woman’s options,” Dr Jeffrey Weitzel of the City of Hope Hospital in Duarte, California, who helped lead the study, said.

Both breast and ovarian cancer are often related to the action on cells by the female hormone oestrogen. It seems to accumulate over a woman’s lifetime.

Usually, the cause (of breast cancer) is unknown but a small percentage of women have mutations in genes known as BRCA1 and BRCA2 that put them at a very high risk of breast cancer.

BRCA mutations account for somewhere between 4% and 10% of breast cancer cases.

Some of these women are opting to have their breasts or ovaries removed, which does seem to prevent the cancer.

Women and doctors are eager to find a less drastic alternative.

Dr Weitzel and colleagues at the University of Southern California and the University of Utah tested a treatment developed by privately held Balance Pharmaceuticals.

Called Libra, it combines a drug called deslorelin with very small amounts of oestrogen and testosterone.

The main purpose of the Phase I trial was to see if it made the women’s breasts easier to look at in mammograms. Young women tend to have “dense” breasts that, when x-rayed, look opaque, making it harder to pick out tiny tumors.

Significant results

“We have significant results already,” Dr Weitzel said.

“In BRCA1 and 2 carriers and women without the mutations we have seen a significant decrease in breast density while bone mineral density remained stable. Their quality of life remained good and unchanged throughout the studies.”

After a year the women stopped using the daily nose spray and within a month or two their normal menstrual periods returned, suggesting they had regained normal fertility.

The drug, a gonadotrophin-releasing hormone agonist, “essentially shuts down the ovary,” Dr Weitzel said.

The hormones in the spray replace the small amount of testosterone produced by the ovaries and are about equal to the smallest amount of oestrogen that a woman produces during her menstrual cycle.

As with birth control pills, the women were given a small amount of progestin, in this case every three months, to protect the lining of the uterus. This caused period-like bleeding.

“Our focus now is on women at high risk – not the average woman,” said Dr Weitzel, who advises Balance Pharmaceuticals. “But it should ultimately act as a contraceptive.”

Libra is in Phase III trials, the last phase of study before a drugmaker can seek US Food and Drug Administration approval, for endometriosis.

The cancer-fighting drug tamoxifen reduces the risk of breast cancer in many women, but has not so far seemed to help women with BRCA mutations.

(Source: ABC Online)