The late stage prostate cancer drugs list is growing for men who have metastatic prostate cancer that has resisted treatment with hormone therapy. Four options on the list are Provenge (sipuleucel-T), Xtandi (enzalutamide), Zytiga (abiraterone), and Xofigo (radium-223).
How do you know which of the late stage prostate cancer drugs is best for you? That decision can be made only after you and your healthcare providers have carefully reviewed your health status, your expectations about treatment, your lifestyle, and the potential risks and benefits of each option. While the first three factors are for you to determine, here is information on the benefits and risks of each of the four late stage prostate cancer drugs to help you make your choice.
What is Provenge
Currently, Provenge is the only immunotherapy drug approved by the Food and Drug Administration (FDA) for the treatment of advanced prostate cancer. Provenge is sometimes called a vaccine for prostate cancer even though technically a vaccine works to prevent disease while Provenge engages the immune system to fight the cancer. Thus Provenge has an advantage over other types of medical treatments and late stage prostate cancer drugs because it supports immune system cells rather than destroys cells, as does chemotherapy and radiation therapy, or stops the production or function of hormones, as does hormone therapy.
Men who are eligible for treatment with Provenge:
- Must have asymptomatic or minimally symptomatic prostate cancer, which means any cancer pain must not be severe enough to require treatment with narcotics
- Must have failed to respond to hormone therapy
- Must have metastatic cancer that has spread to the bones or lymph nodes (but not the brain, liver, or lungs)
- Must not have received chemotherapy within the previous three months
Here are some other things you should know about Provenge:
- Clinical trials show Provenge increased overall survival by 4.1 months in eligible men when compared with placebo. That is, the average survival for men who took Provenge was 25.8 months as compared with 21.7 months in men who took placebo
- Each dose of Provenge is individually formulated and is made from each man’s own blood cells. To make each dose, a sample of a man’s blood cells are collected, modified, and then returned to the patient as an infused dose of Provenge within a few days of collection. This process is done three times over a period of 4 to 5 weeks, which is the entire length of treatment. Thus men need only three doses of Provenge.
- Men who wish to take Provenge must not have used steroids for a specific time period before beginning treatment with the immunotherapy. Therefore, men who may have been taking Zytiga (which requires the use of steroids as part of the treatment) will need to go through a wash out period before taking Provenge.
- Side effects of Provenge (those that affect at least 15% of men) include back pain, chills, fatigue, fever, headache, joint aches, and nausea. Reactions to the infusion occur in about 3.5% of men and can include breathing problems, chills, dizziness, fatigue, fever, headache, high blood pressure, muscle aches, nausea, vomiting, and weakness. Stroke is a rare side effect.
What is Zytiga
Zytiga is a type of hormone therapy, but unlike other drugs in its class, it can stop hormone production (hormones promote prostate cancer growth) in three locations rather than just two: the adrenal glands, the testes, and the prostate tumor. Zytiga focuses its efforts on cytochrome P450 17A1, a protein that has a significant role in the production of testosterone.
Another feature of Zytiga is that it must be taken daily along with prednisone (a steroid) for an average of eight months. Because steroids weaken the integrity of the immune system, men who use Zytiga are at an increased risk of infection.
Here are some other features you should know about Zytiga:
- Clinical trials have shown that men who took Zytiga once daily along with prednisone twice daily had an average overall survival of 14.8 months compared with 10.9 months among men in the placebo group. Thus the average survival advantage for Zytiga is 3.9 months.
- Side effects of Zytiga may include cough, diarrhea, fluid retention, heartbeat disorders, high blood pressure, hot flashes, joint swelling, low potassium levels, muscle aches, upper respiratory tract infections, upset stomach, urinary frequency, and urinary tract infection.
What is Xtandi
Xtandi is a new type of hormone therapy for prostate cancer and also the first one in a new drug class called androgen inhibitors. This means that Xtandi works by inhibiting the activity of an androgen (testosterone), which prostate cancer cells need to grow and reproduce. Men with metastatic prostate cancer resistant to hormone therapy are eligible for treatment with Xtandi if they have also not responded to chemotherapy (docetaxel).
Here are some key features about Xtandi:
- The daily oral treatment course lasts for an average of eight months.
- Results of clinical trials show that Xtandi can improve overall survival by an average of 4.8 months when compared with placebo.
- Side effects include anxiety, back pain, blood in the urine, diarrhea, dizziness, fatigue, headache, hot flashes, joint pain, lower respiratory tract infections, muscle weakness, musculoskeletal pain, sleep problems, spinal cord compression, tingling sensations, tissue swelling, and upper respiratory tract infections. About 1% of men experience seizures.
What is Xofigo
Approved in May 2013, Xofigo is for late stage prostate cancer that has metastasized to the bones but not other organs. It sends radiation directly to the bone tumors without damaging surrounding tissues.
Here are the key details on Xofigo:
- Xofigo is injected six times at four-week intervals.
- Clinical trials showed that the medication has a three-month average survival rate over the placebo.
- Side effects include nausea, vomiting, diarrhea, and swelling of the leg, ankle, and foot.
- It cannot be used with chemotherapy.
Provenge, Zytiga, Xtandi, or Xofigo?
All four late stage prostate cancer drugs are costly. The current cost of a treatment course of Provenge is $93,000, which does not include doctor visits and other additional charges. Xtandi costs about $7,450 per month and typically is taken for eight months. Zytiga hits the wallet at about $5,000 per month, and the average length of treatment is eight months. Xofigo costs $69,000 for the six-month treatment. All four late stage prostate cancer drugs are expected to be covered by Medicare, and patients should check with their individual health insurance providers as well as patient assistance programs from the drug manufacturers for other information.
When choosing among late stage prostate cancer drugs, men should consider all their options and discuss them with their loved ones and medical professionals. Ultimately, the choice between Provenge, Zytiga, Xtandi, Xofigo or other prostate cancer treatments is up to you.
Read more in our Prostate Cancer Health Center.
