Cancer Prostate Cancer Treatment The Use of Zytiga After Lupron to Control Prostate Cancer By Mark Scholz, MD twitter linkedin Mark Scholz, MD, is a board-certified oncologist and expert on prostate cancer. Learn about our editorial process Mark Scholz, MD Medically reviewed by Medically reviewed by Doru Paul, MD on August 20, 2020 Doru Paul, MD, is triple board-certified in medical oncology, hematology, and internal medicine. He is an associate professor of clinical medicine at Weill Cornell Medical College and attending physician in the Department of Hematology Oncology at the New York Presbyterian Weill Cornell Medical Center. Learn about our Medical Review Board Doru Paul, MD Updated on September 17, 2020 Print One of the unique characteristics of prostate cancer is its responsiveness to the withdrawal of testosterone. This “Achilles Heel” of prostate cancer was discovered in the 1940s when surgical removal of the testicles was shown to induce cancer remissions. In 1985, Lupron, an injectable medication that accomplished the same thing was approved by the FDA. Lupron works by tricking the testicles to shut down their production of testosterone. Snap Decision / Photographer's Choice / Getty Images Effectiveness Lupron controls prostate cancer for an average duration of 18 to 24 months in men with metastatic disease. When Lupron stops working, other hormonal agents such as Casodex or Nilandron may provide temporary control, but their duration of effect (keeping the PSA down) usually lasts for less than a year. Controversy has raged in academia about whether a simple decline in PSA levels accurately indicates that a patient’s survival will be extended. So these days, the FDA will only approve a new drug if the pharmaceutical manufacturer documents improved survival in a prospective, placebo-controlled trial. Proving improved survival is a much stiffer challenge than simply showing that medication causes a temporary decline in PSA levels. Zytiga (abiraterone), which was studied in men with metastatic disease that had become resistant to Lupron proved this thesis—volunteers with metastatic, Lupron-resistant prostate cancer who received abiraterone were shown to live 33% longer than men who received a placebo. Zytiga is given in combination with Lupron post-Lupron failure and not alone. Zytiga is a designer drug that works by exploiting the relatively recent discovery that resistance to Lupron (defined as cancer growth despite zero testosterone in the blood) is not a result of the cancer cells having learned to grow without testosterone. Rather, Lupron resistance is a result of prostate cancer cells having learned how to manufacture their own testosterone internally. Its anticancer effect works by blocking an essential enzyme located inside the cancer cell, an enzyme that is an integral component in the synthetic pathway of testosterone. The net result is that the cancer cell is blocked from manufacturing its own testosterone. Side Effects Side effects of Zytiga can include changes in potassium levels in the blood, and in rare cases, liver dysfunction. Zytiga also enhances the action of cholesterol pills like Lipitor and Crestor so their dosage needs to be reduced to compensate. To keep potassium levels in the normal range Zytiga is administered in conjunction with prednisone, a form of cortisone. Cortisone can have side effects too. It is occasionally associated with gastric irritation and stomach ulcers. Higher blood sugar levels can also occur in people who have diabetes. Was this page helpful? Thanks for your feedback! Limiting processed foods and red meats can help ward off cancer risk. These recipes focus on antioxidant-rich foods to better protect you and your loved ones. Sign up and get your guide! Sign Up You're in! Thank you, {{form.email}}, for signing up. There was an error. Please try again. What are your concerns? Other Inaccurate Hard to Understand Submit