Is leuprolide mesylate safe and effective in the treatment of advanced prostate cancer?



This study examined the safety and effectiveness of slow-release leuprolide mesylate (LM) administered by injection under the skin (leuprolide mesylate subcutaneous injectable suspension or LMIS), in the treatment of advanced prostate cancer. This study concluded that this medication is safe and effective in the treatment of advanced prostate cancer.

Advanced prostate cancer is cancer that has spread from the prostate to other parts of the body. Patients with this type of cancer can be treated with androgen deprivation therapy (ADT). This therapy works by reducing the hormones (such as testosterone) that the cancer needs in order to grow. LMIS is an ADT, given by injection under the skin, which reduces the level of testosterone in the body. When testosterone levels fall below a certain point (50ng/dL), these are called “castrate” testosterone levels. This is one of the aims of ADT. 

It is not known if LMIS is safe and effective in the treatment of advanced prostate cancer.

122 patients with advanced prostate cancer were included in this study. Each patient was given two LMIS injections, six months apart. They were followed up for 6 months after the second treatment. 

28 days after treatment, 98.5% of patients had reached a castrate testosterone level. At the end of the study, 97% of patients had a castrate testosterone level. 95.9% of these patients had an even lower testosterone level (less than 20 ng/dL). LMIS reduced PSA levels (a protein elevated in the blood in the presence of cancer) after the first injection. These levels remained low throughout the study. 

Bone pain and urinary symptoms can occur in patients with advanced prostate cancer. These symptoms did not get worse during the study. The most common side effects included hot flushes (48.9%) and high blood pressure (14.6%). 

This study concluded that LMIS is safe and effective in the treatment of advanced prostate cancer.

This study was funded by Foresee Pharmaceuticals Co., Ltd., the manufacturers of LMIS. This was a small study. Larger studies with longer follow up are required.