What Is Enzalutamide (Xtandi®)?
Reviewed by: HU Medical Review Board | Last reviewed: July 2022
Enzalutamide (Xtandi®) is a drug that is used to treat people with prostate cancer. It is also called antiandrogen or a nonsteroidal antiandrogen (NSAA).1
Enzalutamide is for people with:1-4
- Castration-resistant prostate cancer (CRPC)
- Metastatic prostate cancer (cancer that has spread to other areas of the body)
- Non-metastatic prostate cancer (cancer that has not spread beyond the prostate)
- Metastatic castration-sensitive prostate cancer (mCSPC)
- Non-metastatic castration-sensitive prostate cancer with biochemical recurrence at high risk for metastasis
The US Food and Drug Administration (FDA) has also approved talazoparib (Talzenna®) with enzalutamide for homologous recombination repair (HRR) gene-mutated metastatic castration-resistant prostate cancer (mCRPC).5
What are the ingredients in enzalutamide?
Enzalutamide’s active ingredient is an androgen receptor inhibitor in the body.2,3
How does enzalutamide work?
In the body, prostate cancer cells often rely on the male sex hormone testosterone to grow and spread. Enzalutamide works by blocking the binding of testosterone and other androgens (male hormones) to the androgen receptors on prostate cancer cells.2,3
By blocking the androgen receptors, enzalutamide helps to suppress the growth and spread of prostate cancer cells, even in cases where the cancer has become resistant to other treatments, such as surgical castration or medical interventions that lower testosterone levels.2,3
Enzalutamide should be taken at the same time as Gonadotropin-Releasing Hormone agonists (GnRH or LHRH) unless you have had surgery to lower the amount of testosterone in your body.1
In addition, enzalutamide can be used during early stages of other hormone therapies, such as treatment with GnRH, in order to block the initial surge of testosterone that can come along with these drugs. The surge of testosterone at the beginning of some of these treatment methods can contribute to a short-term rapid tumor growth before it is halted, potentially leading to life-threatening issues such as spinal cord compression.1
Enzalutamide comes in a pill form that is taken by mouth. Your provider will determine the right dosage and administration schedule for you. It is important to follow this schedule exactly as instructed.1
What are the possible side effects?
Multiple clinical trials evaluated the safety and efficacy of enzalutamide. But, as with any medicine, there are possible side effects.1-3
The most common side effects of enzalutamide include:1
- Fatigue
- Hot flashes
- Loss of appetite
- Musculoskeletal pain
- Headache
- Weight loss
- Dizziness
- High blood pressure
- Joint pain
These are not all the possible side effects of enzalutamide. Talk to your doctor about what to expect when taking enzalutamide. You also should call your doctor if you have any changes that concern you when taking enzalutamide.
Other things to know
Less common but more serious side effects can accompany enzalutamide including seizures and posterior reversible encephalopathy syndrome (PRES), a reversible condition that affects the brain’s functioning. People taking enzalutamide should be monitored for seizures and PRES.1
Avoid activities where a sudden loss of consciousness (in the event of a seizure) could cause serious harm to you or others around you.1
Always take your medicine as prescribed by your doctor. Talk to your doctor if you have any questions regarding your enzalutamide regimen. Alert your provider immediately if you notice any of the following symptoms:1
- Loss of consciousness
- Seizure
- Headache
- Decreased alertness
- Reduced eyesight, blurred vision, or changes in eyesight
- Confusion, falls, or dizziness
- Chest pain or discomfort
- Shortness of breath
In addition, there is an increased risk of falling or injuries from falls while taking enzalutamide. If you notice signs of a potential infection, or fall and injure yourself, contact your provider immediately.1
You should also contact your provider if you notice any signs of an allergic reaction to the medication, including chest pain or difficulty breathing.1
While taking enzalutamide, males with female partners who are pregnant, or who can become pregnant, should use contraceptives during treatment and for a period of time after completing treatment. Discuss appropriate birth control methods, and how long you need to use them, with your doctor.1
Before starting enzalutamide talk to your provider if you:1
- Have a history of brain injuries, brain tumors, stroke, or seizures
- Have high blood pressure
- Have a partner who is pregnant or could become pregnant
- Have any other medical conditions
Before beginning treatment for prostate cancer, tell your doctor about all your health conditions and any other drugs, vitamins, or supplements you are taking. This includes over-the-counter drugs.
For more information, read the full prescribing information of enzalutamide.