Zytiga Side Effects

Generally Zytiga is well tolerated with few side effects compared to standard chemotherapy. There are some side effects and these are related to the way it works to decrease the level of androgenic hormones. Zytiga inhibits androgen production in the body and this causes a type of male menopause when the testosterone levels fall to zero. This may result in symptoms such as hot flashes, feeling of faintness, dizziness and loss of balance in some cases.

In 50% of men there are no side effects reported and their responses to the drug have been very good. Some patients say they strated feeling better within a few days of taking Zytiga. Other men have seen their PSA plummet when on Zytiga seeing reductions in PSA from over 100 decline to less than 20 within a month in some cases.

In the remaining 50% the side effects are typical of androgen deprivation therapy. Many men may already have experience of these side effects from hormonal therapy having previously been on Lupron or Zoladex.

Here are the manufacturers guidelines on the side effects of Zytiga
About ZYTIGA

"Since its first approval in the U.S. in 2011, ZYTIGA has been approved in 39 additional countries, many thousands of men have received treatment with it, and it is quickly becoming one of the cornerstones of our oncology offerings," said Hait.

ZYTIGA in combination with prednisone was approved by the U.S. Food and Drug Administration (FDA) in April 2011 for the treatment of men with metastatic castration-resistant prostate cancer who have received prior chemotherapy containing docetaxel.  The Phase 3 study for this initial ZYTIGA indication was also unblinded at the interim point, in August 2010, based on a statistically significant improvement in overall survival and an acceptable safety profile.  A subsequent analysis with more mature data confirmed the survival benefit and safety profile.
Indication

ZYTIGA® (abiraterone acetate) in combination with prednisone is indicated for the treatment of patients with metastatic castration-resistant prostate cancer (CRPC) who have received prior chemotherapy containing docetaxel.

Important Safety Information

Contraindications - ZYTIGA® (abiraterone acetate) may cause fetal harm (Pregnancy Category X) and is contraindicated in women who are or may become pregnant.

Hypertension, Hypokalemia and Fluid Retention Due to Mineralocorticoid Excess - Use with caution in patients with a history of cardiovascular disease or with medical conditions that might be compromised by increases in hypertension, hypokalemia, and fluid retention. ZYTIGA® may cause hypertension, hypokalemia, and fluid retention as a consequence of increased mineralocorticoid levels resulting from CYP17 inhibition. Safety has not been established in patients with LVEF <50% or New York Heart Association (NYHA) Class III or IV heart failure because these patients were excluded from the randomized clinical trial. Control hypertension and correct hypokalemia before and during treatment. Monitor blood pressure, serum potassium, and symptoms of fluid retention at least monthly.

Adrenocortical Insufficiency (AI) - AI has been reported in clinical trials in patients receiving ZYTIGA® in combination with prednisone, after an interruption of daily steroids and/or with concurrent infection or stress. Use caution and monitor for symptoms and signs of AI if prednisone is stopped or withdrawn, if prednisone dose is reduced, or if the patient experiences unusual stress. Symptoms and signs of AI may be masked by adverse reactions associated with mineralocorticoid excess seen in patients treated with ZYTIGA®. Perform appropriate tests, if indicated, to confirm AI. Increased dosages of corticosteroids may be used before, during, and after stressful situations.

Hepatotoxicity - Increases in liver enzymes have led to drug interruption, dose modification, and/or discontinuation. Monitor liver function and modify, withhold, or discontinue ZYTIGA® dosing as recommended (see Prescribing Information for more information). Measure serum transaminases [alanine aminotransferase (ALT) and aspartate aminotransferase (AST)] and bilirubin levels prior to starting treatment with ZYTIGA®, every two weeks for the first three months of treatment, and monthly thereafter.  Promptly measure serum total bilirubin, AST, and ALT if clinical symptoms or signs suggestive of hepatotoxicity develop. Elevations of AST, ALT, or bilirubin from the patient's baseline should prompt more frequent monitoring. If at any time AST or ALT rise above five times the upper limit of normal (ULN) or the bilirubin rises above three times the ULN, interrupt ZYTIGA® treatment and closely monitor liver function.