A drug used to treat advanced prostate cancer. It is also being studied in the treatment of other types of cancer. Lupron keeps the testicles from making testosterone by blocking other hormones that are needed to make it. This may stop the growth of cancer cells that need testosterone to grow. Lupron is a type of gonadotropin-releasing hormone (GnRH) agonist. Also called Eligard, leuprolide acetate, and Lupron Depot.