Prostate cancer drugs such as Zoladex, Eligard, Lupron may risk diabetes, death: USFDA

Prostate cancer drugs such as Zoladex from AstraZeneca Plc, Trelstar from Watson Pharmaceuticals Inc could lead to death of patients who use them besides increasing the risks of diabetes and heart attack, US FDA has alerted.

Medicines belonging to the class of gonadotropin-releasing hormone (GnRH) agonists, which are primarily used to treat men with prostate cancer, have been associated with a small increased risk for diabetes, heart attack, stroke, and sudden death in men treated with one of the medications, according to a preliminary and ongoing analysis of several studies by the U.S. Food and Drug Administration.

Other drugs belonging to GnRH class marketed include Eligard, Lupron, Synarel, Vantas, and Viadur. There are also several generic products available.

GnRH agonists are drugs that suppress the production of testosterone, a hormone that is involved in the growth of prostate cancer.

This type of treatment is called androgen deprivation therapy, or ADT. Suppressing testosterone has been shown to shrink or slow the growth of prostate cancer.

Some GnRH agonists are also used in women to help manage the pain caused by endometriosis, to improve anemia associated with uterine fibroids prior to hysterectomy and in some cases for palliative treatment of advanced breast cancer.

Use of these products should not exceed one year for women except in treating breast cancer. There are no known comparable studies that have evaluated the risk of diabetes and heart disease in women taking GnRH agonists.

Some GnRH agonists are also used in children to treat central precocious puberty. There are no known studies that have evaluated the risk of diabetes and heart disease in children taking GnRH agonists.

FDA has advised health care professionals to be aware of these potential risks and carefully weigh the benefits and risks of GnRH agonists when determining a treatment for patients with prostate cancer.

Patients receiving a GnRH agonist should be monitored for the development of diabetes and cardiovascular disease.

Cardiovascular risk factors such as smoking and increases in blood pressure, cholesterol, blood sugar and weight should be managed according to current clinical practice.

US FDA, however, advised patients not to stop treatment with a GnRH agonist unless instructed to do so by a health care professional.

“While our review of these prostate cancer treatments is ongoing and there are some limitations to the data, FDA believes it is important to tell patients and health care professionals that there may be an increased risk of serious side effects,” stated Robert Justice, M.D., director of the Division of Drug Oncology Products in FDA’s Center for Drug Evaluation and Research.

At this time, FDA has not made any conclusions about whether GnRH agonists cause an increase in the risk of diabetes and heart disease in patients receiving one of these medications to treat prostate cancer.

The prostate gland is part of the male reproductive system. Prostate cancer is the second most common type of cancer among men in the United States, behind skin cancer, and usually occurs in older men.

This year an estimated 203,415 new cases of prostate cancer will be diagnosed and about 28,372 men will die from the disease, according to the Centers for Disease Control and Prevention.

Metastatic prostate cancer indicates that the cancer has spread, or metastasized, to the lymph nodes or other parts of the body, mostly to the bones. Castration resistant/hormone-refractory prostate cancer means that the cancer has continued to grow despite the suppression of male hormones that fuel the growth of prostate cancer cells.

More than 80% of all prostate cancer cases are discovered when the disease is limited to the prostate and surrounding organs, while 10-20% of patients are diagnosed when the cancer has already metastasized.