What is Zytiga?

Zytiga is a brand-name prescription medication. It's used to treat two types of prostate cancer:

  • metastatic castration-resistant prostate cancer (CRPC)
  • metastatic high-risk castration-sensitive prostate cancer (CSPC)

Metastatic means the cancer has spread to other parts of the body. Both of these cancers are considered advanced.

The word "castration" refers to the lowering of testosterone levels. Testosterone usually plays a role in stimulating prostate cancer growth. Prostate cancer is considered castration-resistant if the cancer continues to grow or spread even with therapy or surgery to lower testosterone levels.

High-risk castration-sensitive cancer still responds to lowered testosterone levels but requires more aggressive treatment.

Zytiga contains the drug abiraterone acetate. It's a type of medication used in hormone therapy, which is a treatment that lowers the level of male hormones in the body. Reduced levels of male hormones, such as testosterone, help slow or stop the growth of prostate cancer cells.

Zytiga comes as an oral tablet that you take once a day. You'll take Zytiga with a corticosteroid (prednisone) to reduce the risk of certain side effects. In some cases, you'll take Zytiga and prednisone with a different type of hormone therapy to further lower testosterone levels.

Effectiveness

In clinical studies of men with metastatic CRPC, taking Zytiga with prednisone in addition to standard hormone therapy prolonged life by about 4.5 months. For men with CSPC, drug therapy that included Zytiga lowered the risk of death by 34% over 52 months.

Another study looked at men with either metastatic CRPC or CSPC who were starting hormone therapy for the first time. Those who took Zytiga had a three-year survival rate of 83%. This means that they lived for three years after they started taking the drug. Those who received standard therapy had a three-year survival rate of 76%.

Also in this study, Zytiga lowered the risk of death within three years of starting treatment by 37%. This was compared to standard therapy.

FDA approval

The Food and Drug Administration (FDA) approved Zytiga for metastatic CRPC in 2011.

The FDA approved Zytiga for CSPC in 2018.

Zytiga is a brand-name medication that contains abiraterone acetate. Zytiga comes as a 250-mg tablet and a 500-mg tablet.

A generic version of the 250-mg tablet of abiraterone acetate is available. The 500-mg tablet doesn't have a generic version.

Zytiga can cause mild or serious side effects. The following list contains some of the key side effects that you may have while taking Zytiga. This list does not include all possible side effects.

For more information on the possible side effects of Zytiga, talk with your doctor or pharmacist. They can give you tips on how to deal with any side effects that may be bothersome.

More common side effects

The more common side effects of Zytiga include:

  • joint pain, swelling, or stiffness
  • cough
  • diarrhea
  • edema (swelling, typically in your hands, legs, and feet)
  • headache
  • fatigue (lack of energy)
  • flushing (warmth and redness in your skin)
  • nausea
  • vomiting
  • upper respiratory infection (sinus infection or common cold)

Most of these side effects may go away within a few days or a couple of weeks. If they're more severe or don't go away, talk with your doctor or pharmacist.

Serious side effects

Serious side effects of Zytiga can vary in how often they occur.

More common serious side effects

Some common side effects that could result in serious health issues for some people include:

  • Anemia (low level of red blood cells)
  • Hypertension (high blood pressure)
  • Electrolyte disorders (such as low potassium levels)
  • High cholesterol levels
  • High triglyceride levels
  • High blood sugar levels
  • Decrease in liver function (your liver isn't working properly)
  • Urinary tract infections (UTIs). Symptoms can include:
    • burning feeling when you urinate
    • urinating more often than usual but not passing much urine
    • suddenly needing to urinate
  • Kidney problems. Symptoms can include:
    • UTIs (see UTI symptoms above)
    • having to urinate more often than usual
    • needing to urinate often at night
    • blood in urine

Your doctor will monitor you for these side effects at regularly scheduled office visits. If you have serious side effects that can't be controlled, your doctor may lower your Zytiga dose or have you stop treatment.

Rare serious side effects

These serious side effects from Zytiga aren't common, but they can occur. Call your doctor right away if you have serious side effects. Call 911 if your symptoms feel life-threatening or if you think you're having a medical emergency.

Serious side effects and their symptoms can include the following:

  • Serious allergic reaction. Symptoms can include:
    • trouble breathing
    • swelling of your tongue, mouth, or throat
    • angioedema (swelling under your skin, typically in your eyelids, lips, hands, or feet)
  • Liver damage and liver failure. Symptoms can include:
    • jaundice (yellowing of your skin or eyes)
    • dark urine
    • loss of appetite
    • itchy skin
    • stomach pain
    • fatigue (lack of energy)
    • severe nausea and vomiting
  • Cardiac disorders, including abnormal heart rhythm and cardiac arrest (your heart stops beating). Symptoms can include:
    • chest pain
    • feeling like your heart is skipping a beat
    • feeling like your heart is beating too fast or too slow
    • shortness of breath
    • anxiety
    • dizziness
    • fainting
  • Adrenal problems (especially if you stop taking prednisone, are under stress, or get an infection). Symptoms can include:
    • long-lasting fatigue (lack of energy)
    • loss of appetite
    • weight loss
    • muscle weakness
    • stomach pain

Side effect details

You may wonder how often certain side effects occur with this drug, or whether certain side effects pertain to it. Here's some detail on some of the side effects this drug may or may not cause.

Liver damage

Liver damage, severe liver toxicity (when harmful levels of the drug build up in your liver), and liver failure were reported as side effects in clinical studies of Zytiga.

Symptoms of liver problems include jaundice (yellowing of your skin or eyes), urine that's darker than normal, stomach pain, nausea, and vomiting. Liver damage typically occurs during the first three months after starting Zytiga.

Six percent of people who took Zytiga in clinical trials had serious liver damage, based on liver function tests. The test results showed much higher than normal levels of the proteins alanine transaminase (ALT) and aspartate aminotransferase (AST), which the liver releases when it's damaged.

In fact, about 1% of people who took Zytiga in clinical studies stopped taking the drug because of liver damage.

Your doctor will test your liver function before you start taking Zytiga and during your treatment. They'll test levels of ALT, AST, and bilirubin (yellowish pigment that your liver processes). If these levels are too high, you may need to take a lower dose of Zytiga or stop treatment.

If you have moderate liver damage before you begin taking Zytiga, your doctor will start you on a lower dose of Zytiga. They'll also check your liver function more often. If you have severe liver damage, you shouldn't take Zytiga.

Urinary tract infection

In clinical studies, up to 12% of people who took Zytiga had a urinary tract infection (UTI). In about 2% of these cases, the UTI was considered urgent and required antibiotics given as an injection into your vein (intravenous).

Symptoms of a UTI include feeling a burning sensation when you urinate, having to urinate often, and feeling that you have to urinate right away. If you have these symptoms, tell your doctor. You may need an antibiotic to help prevent the infection from spreading.

Kidney effects

Some people in clinical studies of Zytiga had side effects involving their kidneys, including:

  • urinary tract infections (UTIs)
  • having to urinate more often than usual
  • needing to urinate often at night
  • blood in urine

Some of these kidney effects may be related to a UTI, but they may not. If you have any of these symptoms, talk with your doctor about possible treatment options.

Weight loss (not a side effect)

Weight loss wasn't a side effect reported in clinical studies of Zytiga.

But some people may lose weight because of some of the side effects of Zytiga, including diarrhea, nausea, vomiting, and upset stomach. These side effects may prevent these people from eating on a regular schedule. These side effects may also prevent their bodies from taking in enough nutrients.

Weight loss is commonly one of the first signs of cancer, according to the American Cancer Society. During cancer treatment, people may lose weight for many reasons, including medication side effects, depression, and loss of appetite.

Also, unexplained weight loss and muscle loss, called cachexia, is often seen during late-stage cancer due to poor food intake or poor food absorption.

Lastly, weight loss can be a symptom of liver damage or liver failure, which has been reported as a side effect in Zytiga clinical studies.

If you're concerned about your weight loss, talk with your doctor. They can help create a diet plan that provides all the vitamins, minerals, and calories you need. They can also refer you to a dietitian or nutritionist specially trained to help people with cancer.

As with all medications, the cost of Zytiga can vary. To find current prices for Zytiga in your area, check out WellRx.com. The cost you find on WellRx.com is what you would pay without insurance. Your actual cost will depend on your insurance plan, your location, and the pharmacy you use.

Financial and insurance assistance

If you need financial support to pay for Zytiga, or if you need help understanding your insurance coverage, help is available.

Janssen Biotech, Inc., the manufacturer of Zytiga, offers a program called Janssen CarePath. For more information and to find out if you're eligible for support, call 877-227-3728 or visit the program website.

The Zytiga dosage your doctor prescribes will depend on several factors. These include:

  • your liver function (how well your liver is working)
  • the medications you take to treat other conditions

Typically, your doctor will start you on the usual dosage. Then they'll adjust it over time to reach the amount that's right for you. Your doctor will ultimately prescribe the smallest dosage that provides the desired effect.

The following information describes dosages that are commonly used or recommended. However, be sure to take the dosage your doctor prescribes for you. Your doctor will determine the best dosage to suit your needs.

Drug forms and strengths

Zytiga comes in two strengths: a 250-mg uncoated tablet and a 500-mg film-coated tablet.

Dosage for metastatic castration-resistant prostate cancer

The usual recommended dose for metastatic castration-resistant prostate cancer is 1,000 mg of Zytiga taken once a day. The dosage may be taken as two 500-mg tablets or four 250-mg tablets.

With your Zytiga dose, you will also take 5 mg of prednisone by mouth twice a day. (For more information, see "Zytiga and prednisone" below).

If you haven't had your testicles surgically removed, you'll take an additional medication to lower your hormone levels.

Dosage for metastatic high-risk castration-sensitive prostate cancer

The usual recommended dose for metastatic high-risk castration-sensitive prostate cancer is 1,000 mg of Zytiga taken once a day. This dosage may also be taken as two 500-mg tablets or four 250-mg tablets.

With your Zytiga dose, you will also take 5 mg of prednisone by mouth once a day. (For more information, see "Zytiga and prednisone" below).

If you haven't had your testicles surgically removed, you'll take an additional medication to lower your hormone levels.

Dosage for liver disease

If you have moderately severe liver disease, the recommended dosage is 250 mg of Zytiga taken once a day.

What if I miss a dose?

If you miss a dose of Zytiga or prednisone, take a dose the next day at the regular time. Don't take two doses at one time or in the same day. Taking more than one dose of Zytiga or prednisone can increase your risk for side effects.

If you miss more than one dose, call your doctor.

Using a reminder tool can help you remember to take Zytiga every day.

Will I need to use this drug long term?

It depends. Your doctor may want you to continue your Zytiga treatment on a long-term basis if the drug is effective (works well) and safe for you. They'll monitor any side effects and your cancer progress to decide if Zytiga is right for you.

The Food and Drug Administration (FDA) approves prescription drugs such as Zytiga to treat certain conditions. Zytiga may also be used off-label for other conditions. Off-label use is when a drug that's approved to treat one condition is used to treat a different condition.

Zytiga for metastatic prostate cancer

Zytiga is approved to treat two types of metastatic prostate cancer:

  • metastatic castration-resistant prostate cancer (CRPC)
  • metastatic high-risk castration-sensitive prostate cancer (CSPC)

Metastatic prostate cancer is cancer that has spread from the prostate to other areas in the body.

The word "castration" refers to the lowering of testosterone levels. Testosterone usually plays a role in stimulating prostate cancer growth. Prostate cancer is considered castration-resistant if the cancer continues to grow or spread even with therapy or surgery to lower testosterone levels.

High-risk castration-sensitive cancer still responds to lowered testosterone levels but requires more aggressive treatment.

For either type of cancer, Zytiga is used with prednisone, a corticosteroid that helps lessen certain side effects.

Zytiga is also taken with other hormone therapy called androgen deprivation therapy (ADT), which further reduces male hormone levels. Examples of ADT options include:

  • leuprolide acetate (Eligard)
  • goserelin acetate (Zoladex)
  • histrelin acetate (Vantas)
  • degarelix (Firmagon)

An alternative to ADT medication is bilateral orchiectomy (surgical removal of the testicles), which also lowers testosterone levels.

Uses that are not approved

Zytiga may be used off-label for other uses. Off-label use is when a drug that's approved for one purpose is used for another purpose.

Nonmetastatic prostate cancer

Zytiga isn't FDA-approved to treat nonmetastatic prostate cancer. But the American Urological Association recommends Zytiga as an option for people if all of the following apply:

  • They have nonmetastatic castration-resistant prostate cancer (CRPC).
  • Their risk of developing metastatic prostate cancer is high.
  • They don't want or can't take standard therapy.
  • They're unwilling to "watch and wait" under their doctor's supervision.

In one clinical study, about half of the people who received Zytiga had nonmetastatic CRPC. In this group, the use of Zytiga with standard therapy didn't improve the rate of overall survival by a significant amount compared to standard therapy alone. But people with nonmetastatic prostate cancer did go longer without having a significant change in cancer growth or needing to change therapy.

There are other drugs available that can treat your condition. Some may be better suited for you than others. If you're interested in finding an alternative to Zytiga, talk with your doctor to learn more about other medications that may work well for you.

Alternatives for prostate cancer

Examples of other drugs that may be used to treat prostate cancer include:

  • enzalutamide (Xtandi)
  • docetaxel (Taxotere)
  • sipuleucel-T (Provenge)
  • cabazitaxel (Jevtana)
  • radiotherapy (such as Xofigo)

You may wonder how Zytiga compares to other medications that are prescribed for similar uses. Here we look at how Zytiga and Xtandi are alike and different.

Zytiga contains the drug abiraterone acetate. Xtandi contains the drug enzalutamide.

Both drugs decrease the activity of male hormones but work in slightly different ways. Zytiga blocks the production of certain male hormones. Xtandi helps prevent male hormones from attaching to their receptors (proteins on prostate cancer cells). In both cases, the drugs help stop the spread of prostate cancer.

Uses

Zytiga and Xtandi are both used to treat castration-resistant prostate cancer (CRPC). Castration-resistant cancer continues to spread despite the use of drugs that lower male hormone levels.

Zytiga is specifically FDA-approved to treat metastatic CRPC. The Food and Drug Administration (FDA) has also approved Zytiga to treat metastatic high-risk castration-sensitive prostate cancer (CSPC). Metastatic prostate cancer has spread from the prostate to other areas in the body. CSPC still responds to hormone therapy.

Xtandi is FDA-approved for metastatic and nonmetastatic CRPC. Nonmetastatic prostate cancer has not spread to other parts of the body yet.

Both drugs are taken along with other hormone therapy or following surgery to remove your testicles. This helps further reduce the effects of androgens (male hormones such as testosterone) on cancer cells.

Drug forms and administration

Zytiga and Xtandi are both given as pills. You take them once a day.

Zytiga comes as a 250-mg tablet and a 500-mg tablet. The usual dosage is 1,000 mg once a day. You should take Zytiga without food (on an empty stomach). You take Zytiga along with prednisone, a corticosteroid that helps reduce certain side effects.

Xtandi comes as a 40-mg capsule. The usual dosage is 160 mg once a day. You can take it with or without food.

Your doctor may change your dose of Zytiga or Xtandi if you're taking other medications that affect the levels of Zytiga or Xtandi in your body. You may also need a lower dose of Zytiga if you have liver disease.

Side effects and risks

Zytiga and Xtandi work in slightly different ways, so they have some similar and some different side effects. Below are examples of these side effects.

More common side effects

These lists contain examples of more common side effects that can occur with Zytiga, Xtandi, or with both drugs (when taken individually).

  • Can occur with Zytiga:
    • cough
  • Can occur with Xtandi:
    • weakness
    • vertigo (dizziness)
    • lack of appetite
    • weight loss
  • Can occur with both Zytiga and Xtandi:
    • joint pain
    • headache
    • fatigue (lack of energy)
    • flushing (warmth and redness in your skin)
    • diarrhea
    • edema (swelling, typically in your hands, legs, and feet)
    • nausea
    • vomiting
    • upper respiratory infection (sinus infection or common cold)

Serious side effects

These lists contain examples of serious side effects that can occur with Zytiga, Xtandi, or with both drugs (when taken individually).

  • Can occur with Zytiga:
    • anemia (low level of red blood cells)
    • electrolyte disorders (such as low potassium levels)
    • high cholesterol and triglyceride levels
    • liver damage or liver failure
    • adrenal problems, such as low cortisol levels
    • cardiac disorders, including abnormal heart rhythm and cardiac arrest (your heart stops beating)
    • urinary tract infections
    • kidney problems
  • Can occur with Xtandi:
    • seizures
    • neurological disorder affecting the brain
    • ischemic heart disease (lack of blood flow to the heart)
    • falls and fractures
  • Can occur with both Zytiga and Xtandi:
    • severe allergic reaction
    • hypertension (high blood pressure)
    • high blood sugar levels

Effectiveness

These drugs haven't been directly compared in clinical studies, but studies have found both Zytiga and Xtandi to be effective for treating metastatic castration-resistant prostate cancer.

The American Urological Association, the National Comprehensive Cancer Network, and the American Society of Clinical Oncology all recommend either Zytiga or Xtandi as treatment options for metastatic CRPC.

Costs

Zytiga and Xtandi are both brand-name drugs. There's currently a generic form of Zytiga, but there isn't a generic form of Xtandi. Brand-name medications usually cost more than generics.

The brand-name form of Zytiga costs much more than the generic form.

According to estimates from WellRx.com, the brand-name form of Zytiga generally costs less than Xtandi. The actual price you pay will depend on your insurance plan, your location, and the pharmacy you use.

You may wonder how Zytiga compares to other medications that are prescribed for similar uses. Below are comparisons between Zytiga and several medications.

Zytiga vs. Casodex

Zytiga contains the drug abiraterone acetate. Casodex contains the drug bicalutamide.

Both drugs decrease the activity of male hormones, but they work in different ways. Zytiga prevents the production of certain male hormones. Casodex blocks male hormones from attaching to their receptors (proteins on prostate cancer cells). Both actions help stop the spread of prostate cancer.

Uses

Both Zytiga and Casodex are used to treat metastatic prostate cancer. Metastatic prostate cancer has spread from the prostate to other areas of the body.

The Food and Drug Administration (FDA) has approved Zytiga to treat metastatic castration-resistant prostate cancer (CRPC). Metastatic CRPC continues to grow despite the use of drugs that lower male hormone levels.

Zytiga is also approved to treat metastatic high-risk castration-sensitive prostate cancer. This type of prostate cancer still responds to drugs that lower male hormone levels.

Casodex is FDA-approved to treat stage D2 metastatic prostate cancer. Stage D2 prostate cancer has metastasized (spread) to more distant bones, like the spine or ribs.

Drug forms and administration

Zytiga and Casodex are both given as pills. You take them once a day.

Zytiga comes in two strengths: a 250-mg tablet and a 500-mg tablet. The usual dosage is 1,000 mg once a day. You should take the drug without food (on an empty stomach). You take Zytiga with prednisone (a corticosteroid) to reduce certain side effects.

You may need a different dose of Zytiga if you're taking certain drugs that can affect Zytiga levels in the body or if you have liver disease.

Casodex comes as a 50-mg tablet. The usual dosage is 50 mg of Casodex once a day.

Both drugs must be taken with either additional hormone therapy or after surgery to remove your testicles. This helps further reduce the effects of androgens (male hormones such as testosterone) on prostate cancer cells.

Side effects and risks

Zytiga and Casodex work in different ways in the body. Therefore, they have some similar and some different common and serious side effects.

More common side effects

These lists contain examples of more common side effects that can occur with Zytiga, Casodex, or with both drugs (when taken individually).

  • Can occur with Zytiga:
    • joint pain
    • fatigue (lack of energy)
  • Can occur with Casodex:
    • body pain (in back, stomach, or pelvis)
    • weakness
    • constipation
    • shortness of breath
    • dizziness
    • blood in urine
  • Can occur with both Zytiga and Casodex:
    • flushing (warmth and redness in your skin)
    • upper respiratory infection, such as a sinus infection or common cold
    • nausea
    • edema (swelling, typically in your hands, feet, and legs)
    • diarrhea
    • cough
    • headache
    • vomiting
    • needing to urinate often at night

Serious side effects

These lists contain examples of serious side effects that can occur with Zytiga, Casodex, or with both drugs (when taken individually).

  • Can occur with Zytiga:
    • hypertension (high blood pressure)
    • electrolyte disorders (such as low potassium levels)
    • high cholesterol and triglyceride levels
    • adrenal problems, such as low cortisol levels
    • cardiac disorders, such as abnormal heart rhythm or cardiac arrest (your heart stops beating)
    • urinary tract infections
    • kidney problems
  • Can occur with Casodex:
    • breast growth and pain
  • Can occur with both Zytiga and Casodex:
    • severe allergic reaction
    • anemia (low level of red blood cells)
    • liver damage or liver failure
    • high blood sugar levels

Effectiveness

These drugs haven't been directly compared in clinical studies, but studies have found both Zytiga and Casodex to be effective for treating metastatic castration-resistant prostate cancer (CRPC).

The National Comprehensive Cancer Network recommends both Zytiga and Casodex as treatment options for metastatic CRPC.

Costs

Zytiga and Casodex are both brand-name drugs. There are generic forms of both Zytiga and Casodex. Brand-name medications usually cost more than generics.

According to estimates from WellRx.com, brand-name Zytiga and generic Zytiga generally cost more than either form of Casodex. The actual cost you pay for the drug will depend on your insurance plan, your location, and the pharmacy you use.

Zytiga vs. Yonsa

Zytiga and Yonsa contain the same drug: abiraterone acetate. But Yonsa was created as a much smaller particle of abiraterone acetate so your bloodstream can better absorb the drug. You can take Yonsa with or without food because of its smaller particle size.

Uses

Zytiga and Yonsa are both FDA-approved to treat metastatic castration-resistant prostate cancer (CRPC). Metastatic prostate cancer has spread from the prostate to other areas in the body. Metastatic CRPC continues to grow despite therapy that lowers male hormone levels.

Zytiga is also FDA-approved to treat metastatic high-risk castration-sensitive prostate cancer (CSPC). CSPC still responds to drug therapy that lowers male hormone levels.

Drug forms and administration

Zytiga and Yonsa are both given as pills once a day.

Zytiga comes in two strengths: a 250-mg tablet and a 500-mg tablet. The usual dosage is 1,000 mg once a day. You should take Zytiga without food (on an empty stomach). You take the drug with prednisone (a corticosteroid) to reduce certain side effects.

Your doctor may prescribe a different dose of Zytiga if you're taking certain drugs that affect Zytiga levels in your body or if you have liver disease.

Yonsa comes as a 125-mg tablet. The usual dosage is 500 mg of Yonsa once a day. You take Yonsa with methylprednisolone (a corticosteroid) to reduce certain side effects.

Both drugs must be taken with either additional hormone therapy or after surgery to remove your testicles. This helps further reduce the effects that androgens (male hormones such as testosterone) have on cancer cells.

Side effects and risks

Zytiga and Yonsa are very similar drugs, therefore they have many of the same side effects.

More common side effects

This lists contains examples of more common side effects that can occur with Zytiga and Yonsa:

  • joint pain or swelling
  • cough
  • diarrhea
  • edema (swelling, typically in your hands, legs, and feet)
  • fatigue (lack of energy)
  • flushing (warmth and redness in your skin)
  • nausea or vomiting
  • upper respiratory infection, such as a sinus infection or common cold
  • headaches
  • shortness of breath
  • bruising

Serious side effects

These lists contain examples of serious side effects that can occur with both Zytiga and Yonsa:

  • hypertension (high blood pressure)
  • anemia (low level of red blood cells)
  • high cholesterol and triglyceride levels
  • electrolyte disorders (such as low potassium levels)
  • high blood sugar levels
  • adrenal problems, such as low cortisol levels
  • urinary tract infections
  • liver damage or liver failure
  • cardiac disorders, such as abnormal heart rhythm or cardiac arrest (your heart stops beating)
  • kidney problems
  • low levels of white blood cells

Effectiveness

These drugs haven't been directly compared in clinical studies, but studies have found both Zytiga and Yonsa to be effective for treating metastatic castration-resistant prostate cancer.

Zytiga and Yonsa are two versions of the same drug. Yonsa was created as a much smaller particle of abiraterone acetate so your bloodstream can better absorb the drug. You can take Yonsa with or without food because of its smaller particle size. But you can expect the two drugs to have very similar effects on the body.

The National Comprehensive Cancer Network recommends both Zytiga and Yonsa as treatment options for metastatic CRPC.

Costs

Zytiga and Yonsa are both brand-name drugs. There are currently no generic forms of Yonsa, but there is a generic form of Zytiga available. Brand-name medications usually cost more than generics.

According to estimates from WellRx.com, brand-name Zytiga and generic Zytiga generally cost more than Yonsa. The actual cost you pay for the drug will depend on your insurance plan, your location, and the pharmacy you use.

You take Zytiga with another drug called prednisone. Prednisone is a prescription corticosteroid medication.

Zytiga prevents your adrenal glands (which make and release hormones) from making cortisol. Cortisol is a hormone that plays a role in many important bodily functions. Some of these include maintaining blood pressure, regulating sleep-wake cycles, and controlling blood sugar levels.

Prednisone helps replace low cortisol levels, so it keeps these important bodily functions working properly. Prednisone also helps you avoid the side effects of low cortisol levels. That's why you take prednisone and Zytiga together.

If you have metastatic castration-resistant prostate cancer, you will take 5 mg of prednisone twice a day.

If you have metastatic high-risk castration-sensitive prostate cancer, you will take 5 mg of prednisone once a day.

You typically take Zytiga with prednisone and another hormone therapy drug. This second type of hormone therapy is referred to as androgen deprivation therapy (ADT). ADT medications help prevent the testicles from making male hormones that encourage prostate cancer to grow.

The adrenal glands and prostate cancer cells themselves also make male hormones in small amounts. Zytiga helps prevent these secondary areas of the body from producing testosterone.

Examples of ADT drugs include:

  • leuprolide acetate (Eligard)
  • goserelin acetate (Zoladex)
  • histrelin acetate (Vantas)
  • degarelix (Firmagon)

There's no interaction between Zytiga and alcohol. But Zytiga has caused liver toxicity (dangerous levels of the drug that build up in the liver) in some people. Drinking too much alcohol may increase the risk of liver damage in people who are taking Zytiga.

If you take Zytiga, talk with your doctor about whether drinking alcohol is safe for you.

Zytiga can interact with several other medications. It can also interact with certain supplements and foods.

Different interactions can cause different effects. For instance, some interactions can affect how well a drug works, while others can increase the number of side effects or make them more severe.

Zytiga and other medications

Below is a list of medications that can interact with Zytiga. This list does not contain all drugs that may interact with Zytiga.

Before taking Zytiga, talk with your doctor and pharmacist. Tell them about all prescription, over-the-counter, and other drugs you take. Also tell them about any vitamins, herbs, and supplements you use. Sharing this information can help you avoid potential interactions.

If you have questions about drug interactions that may affect you, ask your doctor or pharmacist.

Zytiga and Xofigo

Don't take Zytiga with Xofigo, a radioactive medication, unless you're taking them together in a clinical trial. In a clinical study, people who took Zytiga with Xofigo had a greater risk for bone fractures and death. This was compared to people who took Zytiga and a placebo (a dummy drug that doesn't work). If you have questions about Xofigo, talk with your doctor.

Zytiga and Provenge

There's no interaction between Zytiga and Provenge (sipuleucel-T). Provenge is a type of vaccine that makes your immune system more active in fighting prostate cancer.

One clinical study looked at how people's immune systems responded to Provenge therapy. An immune system response shows that Provenge is working. The results of this study were similar in people who took Zytiga with Provenge and in people who used Zytiga after taking Provenge.

However, current treatment guidelines don't recommend using Zytiga and Provenge together. Instead, the guidelines recommended taking one drug or the other as a possible treatment.

Zytiga and certain seizure medications

Taking Zytiga with certain seizure medications can increase how quickly your body gets rid of Zytiga. This can lower the amount of Zytiga in your body and make the drug less effective (not work as well). Examples of these seizure medications include:

  • phenytoin (Dilantin, Phenytek)
  • carbamazepine (Carbatrol, Epitol, Equetro, Tegretol, Tegretol-XR, or Teril)
  • phenobarbital

In some instances, your doctor may want you to take Zytiga with one of these seizure medications. If that's the case, they may increase your Zytiga dose to 1,000 mg twice a day.

Zytiga and certain tuberculosis medications

Taking Zytiga with certain tuberculosis medications can increase how quickly your body gets rid of Zytiga. This may make Zytiga less effective (not work as well) by lowering the amount of the drug in your body. Examples of these tuberculosis medications include:

  • rifampin (Rifadin, Rimactane)
  • rifabutin (Mycobutin)
  • rifapentine (Priftin)

In some instances, your doctor may want you to take Zytiga with one of these tuberculosis medications. If that's the case, they may increase your Zytiga dose to 1,000 mg twice a day.

Zytiga and drugs that are broken down by the enzyme CYP2D6

Taking Zytiga with drugs that are metabolized (broken down) by the enzyme CYP2D6 can increase the levels of those drugs in your body. (An enzyme is a protein that causes chemical reactions in your body.) This is because Zytiga blocks CYP2D6 from breaking down those drugs the way the enzyme normally would. Higher levels of these drugs may increase your risk for side effects.

Examples of drugs broken down by CYP2D6 include:

  • dextromethorphan (Delsym)
  • certain antidepressants, such as desipramine (Norpramin), nortriptyline (Pamelor), and venlafaxine (Effexor XR, Pristiq)
  • atomoxetine (Strattera)
  • thioridazine
  • nebivolol (Bystolic)

If you're taking Zytiga with a drug that's metabolized by CYP2D6, your doctor will closely monitor your side effects. You may need a lower dose of Zytiga or an alternative for the other medication.

Zytiga and drugs that are broken down by the protein CYP2C8

Taking Zytiga with drugs that are metabolized (broken down) by the protein CYP2C8 can increase the levels of those drugs in your body. This is because Zytiga blocks CYP2C8 from breaking down those drugs the way the protein normally would. Higher levels of these drugs can increase your risk for side effects.

Examples of these drugs include pioglitazone (Actos) and repaglinide (Prandin).

If you're taking Zytiga with a drug that's broken down by CYP2C8, your doctor will monitor you closely for side effects. You may need an alternative to that medication or a lower dose of Zytiga.

Zytiga and St. John's wort

Taking Zytiga with St. John's wort can decrease the amount of Zytiga in your body. This is because St. John's wort increases how quickly your body gets rid of Zytiga. Low levels of Zytiga can decrease how well it will work for you.

In some instances, your doctor may want you to take Zytiga and St. John's wort. If that's the case, your doctor may increase your Zytiga dose to 1,000 mg twice a day.

Zytiga and foods

Don't take Zytiga at the same time that you eat food. Eating food when you take the drug will increase the amount of Zytiga that your body absorbs (takes in) at one time. This increases your risk for side effects. Take Zytiga either one hour before a meal or two hours after a meal.

However, according to current treatment guidelines, taking Zytiga with food may be an option. Talk with your doctor if you have questions.

You should take Zytiga according to your doctor or healthcare provider's instructions.

Timing

Take Zytiga once a day, either one hour before a meal or two hours after a meal. Taking the medication at the same time each day can help you remember your dose.

And medication reminders can help make sure that you don't miss a dose.

Taking Zytiga with food

Take Zytiga on an empty stomach, either one hour before a meal or two hours after a meal. Taking Zytiga on an empty stomach helps decrease your risk for side effects.

Take your dose of Zytiga with a glass of water.

However, according to current treatment guidelines, taking Zytiga with food may be an option. Talk with your doctor if you have questions.

Can Zytiga be crushed, split, or chewed?

No. You shouldn't crush, split, or chew Zytiga. You must swallow it whole.

Zytiga contains the drug abiraterone acetate, which is used to treat two types of metastatic prostate cancer:

  • Metastatic castration-resistant prostate cancer.* This is prostate cancer that has metastasized (spread) from the prostate to another area in the body. It's castration-resistant, which means it keeps growing despite drug therapy or surgery that lowers testosterone levels.
  • Metastatic high-risk castration-sensitive prostate cancer. This is also prostate cancer that has metastasized (spread) from the prostate to another area in the body. High-risk prostate cancer is expected to grow and spread quickly. Castration-sensitive prostate cancer responds to drug therapy or surgery that lowers testosterone levels.

* The word "castration" is used because drug therapy is considered an alternative to surgically removing the testicles. Both of these methods decrease testosterone levels.

Androgens (male hormones such as testosterone) encourage prostate cancer cells to grow. Zytiga belongs to a class of medications called androgen biosynthesis inhibitors. These drugs inhibit (block) the production of androgens.

Specifically, Zytiga blocks the activity of an enzyme (a protein that causes chemical reactions in the body) called CYP17. The CYP17 enzyme is involved in the production of testosterone and other male hormones. These hormones are made in the testicles, the adrenal glands, and prostate cancer cells.

Zytiga decreases the amount of testosterone that prompts cancer to grow. But it doesn't block all testosterone production in the body, so you need to take Zytiga with other hormone therapy.

How long does it take to work?

Each person's body will respond differently to Zytiga. But drugs like Zytiga that affect steroid hormones may start to lower testosterone levels in days to weeks. Because the goal of Zytiga treatment is to stop the growth of cancer, it's not possible to say for sure how quickly the lower testosterone levels will affect cancer cells.

Zytiga isn't intended for use by women.

Pregnant women shouldn't take or handle Zytiga. In animal studies, taking Zytiga while pregnant had harmful and fatal effects on offspring.

Women who are pregnant or may become pregnant must wear protective gloves while handling Zytiga 250-mg uncoated tablets or damaged Zytiga 500-mg coated tablets. Unprotected exposure to the drug may harm the developing baby.

If men who are taking Zytiga are sexually active with a pregnant woman, they should use a condom during treatment and for three weeks after the final dose. If they have female partners who can become pregnant, the couple should use two forms of birth control (for example, condoms and oral birth control pills).

In animal studies, males who were given Zytiga had reduced fertility (ability to make a woman pregnant). This effect was reversible after 16 weeks following the last dose. But animal studies don't always predict what will occur in humans.

It's not known whether Zytiga passes into breast milk.

If you're considering taking Zytiga while you're breastfeeding, talk with your doctor. They may recommend that you either stop breastfeeding or take a drug other than Zytiga.

Here are answers to some frequently asked questions about Zytiga.

Can I use Zytiga after using Xtandi?

Yes. You can take Zytiga after taking Xtandi.

According to current treatment guidelines, Zytiga is a treatment option for people whose cancer got worse while taking Xtandi or after taking Xtandi.

On the other hand, Xtandi is a treatment option for people whose cancer got worse while taking Zytiga or after taking Zytiga.

Can I take Zytiga without prednisone?

It's recommended that you take Zytiga with the corticosteroid prednisone to reduce some of the side effects that happen because of low hormone levels. Some of these side effects include high blood pressure, low potassium levels, and edema (swelling, typically in your hands, legs, and feet).

In one clinical study, people took prednisolone (a corticosteroid that's similar to prednisone) with Zytiga. In another clinical study involving older adults, Zytiga was taken with either prednisone or prednisolone. These combinations were found to be safe and effective for treating metastatic prostate cancer when taken with standard hormone therapy.

And in another study, switching from prednisone to dexamethasone (a corticosteroid similar to prednisone) was safe for people with advanced cancer.

A small clinical study found that some people may be able to take Zytiga without prednisone. However, they'll need to be monitored more closely by their doctor. Don't stop taking prednisone unless your doctor tells you to do so.

Some doctors may also prescribe a different corticosteroid, such as prednisolone, methylprednisolone, or dexamethasone, that you take with Zytiga. Prescribing a different corticosteroid than the one the Food and Drug Administration (FDA) approved is considered off-label use.

Is Zytiga a form of chemotherapy?

No. Zytiga isn't a form of chemotherapy. Zytiga is a type of hormone therapy that helps fight prostate cancer. It works by reducing the amount of male hormones in the body.

Chemotherapy drugs, such as docetaxel (Taxotere) or cabazitaxel (Jevtana), work differently from hormone therapy drugs. Chemotherapy drugs attack many different types of rapidly growing cells in the body, including cancer cells. But the drugs also attack newly forming blood cells, hair follicle cells, and cells on the linings of the mouth and intestines. Chemotherapy drugs typically have many side effects because of how they affect the body.

Hormone therapy is usually a first-choice therapy for treating prostate cancer. Chemotherapy can be used with hormone therapy or by itself to treat late-stage cancer. However, Zytiga isn't one of the hormone therapies currently recommended to be used in combination with chemotherapy.

How long will I need to be treated with Zytiga?

You and your doctor will discuss how effective and safe Zytiga is for you. You will likely take Zytiga for as long as it helps prevent cancer from growing and for as long as you can handle the side effects. This may be anywhere from months to years.

Does Zytiga affect my testosterone levels?

Yes. Zytiga helps slow or stop the growth of prostate cancer by decreasing the amount of testosterone and other male hormones in your body. Zytiga lowers testosterone levels by blocking the production of other steroids that help create testosterone. It also lowers the levels of another important male hormone called dihydrotestosterone.

What is the life expectancy for someone taking Zytiga?

Life expectancy (the number of years you will likely live) is based on several factors. These include your age, overall health status, the stage (how advanced) your cancer is, and other factors. Life expectancy is different for every person. The number of years you will likely live will help guide therapy options for your prostate cancer.

In clinical studies, people with metastatic castration-resistant prostate cancer who took Zytiga lived about 4.5 months longer than people who didn't take Zytiga. But each person's response to Zytiga treatment will be unique and based on their own life expectancy factors.

Before taking Zytiga, talk with your doctor about your health history. Zytiga may not be right for you if you have certain medical conditions. These include:

Heart disease

Zytiga may cause serious heart problems (such as heart attack or stroke) and death. Before you start taking Zytiga, talk with your doctor about your history of heart disease. This includes heart failure, arrhythmia (abnormal heart rhythm), and heart attack.

Your doctor will check you for heart disease, as well as for high blood pressure, low potassium levels, and fluid retention (see below). If needed, they'll recommend treatment for heart disease before and during your Zytiga treatment. Zytiga may not be right for people with a very high risk for serious heart problems.

Hypertension

Zytiga can cause hypertension (high blood pressure), which increases your risk for heart problems such as heart attack or stroke.

Your doctor will check your blood pressure before you start Zytiga and at least once a month while you take the drug. If needed, they'll recommend treatment options to control your blood pressure before and during your Zytiga treatment.

Hypokalemia

Zytiga can decrease blood levels of potassium. This is an important electrolyte (a mineral) that your body needs for proper nerve, muscle, and heart function.

Your doctor will check your potassium levels before you start Zytiga and at least once a month while you take the drug. If needed, they'll recommend treatment options to correct your potassium levels before and during your Zytiga treatment.

Edema or fluid retention

Zytiga can cause edema (swelling, typically in your hands, legs, and feet).

Before starting Zytiga, tell your doctor about any swelling that you have. They will check to see if the swelling is caused by a disease that should be treated before you start taking Zytiga. If needed, they'll recommend treatment options to help prevent edema before or during your Zytiga treatment.

Adrenal insufficiency

Zytiga and prednisone (a corticosteroid drug that you take with Zytiga) have been linked to adrenal problems. (Adrenal glands make and release hormones.) The link was very strong in people who were under stress, had an infection, or stopped corticosteroid therapy.

Before starting Zytiga, tell your doctor if you've had adrenal problems in the past. They may monitor you more closely for side effects or recommend an alternate therapy.

Pituitary disorders

Zytiga works on hormones that are partly controlled by the pituitary gland.

Before starting Zytiga, tell your doctor if you've had pituitary problems in the past. They may monitor you more closely while you take Zytiga.

Liver disease or liver problems

Zytiga has been linked to liver damage, hepatitis, liver failure, and death. People who had liver disease or liver problems in the past have a greater risk of liver damage if they take Zytiga.

Your doctor will check how your liver is working before you start Zytiga. They'll continue to check your liver function every two weeks for three months, and then every month after that. If you develop liver problems during treatment, you may need to stop taking Zytiga for a time or take a lower dose.

People with moderate liver disease should start with a lower dose of Zytiga. People with severe liver disease shouldn't take Zytiga.

Taking more than the recommended dosage of Zytiga can increase your risk for common and serious side effects. This list does not include all possible overdose symptoms.

Overdose symptoms

Symptoms of an overdose can include:

  • diarrhea
  • nausea and vomiting
  • high blood pressure
  • abnormal heart rhythm
  • cardiac arrest (your heart stops beating)
  • liver damage or liver failure

What to do in case of overdose

If you think you've taken too much of this drug, call your doctor. You can also call the American Association of Poison Control Centers at 800-222-1222 or use their online tool. But if your symptoms are severe, call 911 or go to the nearest emergency room right away.

When you get Zytiga from the pharmacy, the pharmacist will add an expiration date to the label on the bottle. This date is typically one year from the date they dispensed the medication.

The expiration date helps guarantee the effectiveness of the medication during this time. The current stance of the Food and Drug Administration (FDA) is to avoid using expired medications. If you have unused medication that has gone past the expiration date, talk with your pharmacist about whether you might still be able to use it.

Storage

How long a medication remains good can depend on many factors, including how and where you store the medication.

Store Zytiga pills at room temperature (68°F to 77°F/20°C to 25°C) away from the reach of children.

Disposal

If you no longer need to take Zytiga and have leftover medication, it's important to dispose of it safely. This helps prevent others, including children and pets, from taking the drug by accident. It also helps keep the drug from harming the environment.

The FDA website provides several useful tips on medication disposal. You can also ask your pharmacist for information on how to dispose of your medication.

The following information is provided for clinicians and other healthcare professionals.

Indications

Zytiga is approved by the Food and Drug Administration (FDA) to be used in combination with prednisone for the treatment of metastatic castration-resistant prostate cancer and metastatic high-risk castration-sensitive prostate cancer.

Mechanism of action

Zytiga contains the prodrug abiraterone acetate, which is an androgen biosynthesis inhibitor. It's converted through hydrolysis to the active metabolite abiraterone.

Zytiga inhibits the enzyme 17α-hydroxylase/C17,20-lyase (CYP17), which is expressed in the testicles, adrenal glands, and prostatic tumor tissue. Inhibition of the CYP17 enzyme decreases production of the testosterone precursors dehydroepiandrosterone (DHEA) and androstenedione, which ultimately lowers the levels of serum testosterone and dihydroxy testosterone.

Inhibition of CYP17 also increases mineralocorticoid production by the adrenal glands.

Pharmacokinetics and metabolism

Maximum plasma concentrations are reached two hours after oral administration of Zytiga. Meal fat composition significantly alters systemic exposure, so Zytiga should be taken on an empty stomach.

Zytiga is highly bound to plasma proteins (albumin and alpha-1 acid glycoprotein) and is metabolized via non-CYP mediated hydrolysis. Approximately 88% of the dose is excreted in feces. Terminal half-life is approximately 12 hours. Hepatic impairment prolongs exposure (see dosing adjustment recommendations).

Zytiga is a substrate of cytochrome P450 (CYP) 3A4 and an inhibitor of CYP2D6 and CYP2C8.

Contraindications

Zytiga can cause harm to a developing fetus and loss of pregnancy.

Note: Men with female partners of reproductive potential should use effective contraception during Zytiga treatment and for three weeks after the final dose.

Storage

Zytiga tablets should be stored at room temperature (68°F to 77°F/20°C to 25°C). Keep out of reach of children.