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Home » Prostate and Urological Health » Formulation Development for Prostate Cancer Offers Hope for Some Patients

The deadliest form of prostate cancer is the most difficult to treat, but treatment formulation offers increased administration flexibility.

Prostate cancer remains a deadly disease. It’s estimated that this year alone nearly 200,000 men will be diagnosed — and more than 33,000 will die from some form of the disease. Many of those deaths will be the result of metastatic castration-resistant prostate cancer (mCRPC); up to 75 percent of prostate cancer patientswill progress to the metastatic form of the disease, and historically the median survival for men diagnosed with mCRPC is less than two years.

The good news is, treatment for mCRPC has improved dramatically. Prior to the introduction of docetaxel chemotherapy in 2004, there really was no effective treatment for mCRPC. Luckily for patients, that has changed.


Treating mCRPC remains challenging because the cancer has stopped responding to hormone therapies, grows despite low testosterone levels, and has spread to other parts of the body, including the lymph nodes, bones, liver, or brain. Recent years have seen the introduction of newer therapies for mCRPC, including abiraterone acetate, which interferes with androgen production in the testes, the adrenal glands, and tumors.

While abiraterone acetate is an effective treatment for mCRPC, typical dosing of 1,000mg orally once a day (along with prednisone) requires the patient to plan their meals carefully in order to ensure they take their medication at least one hour before or two hours after eating. Failure to abide by this recommendation can lead to increased exposure of the drug and adverse reactions. There can also be blood level variations with traditional formulations.

A flexible formulation

Oral medications must be absorbed by the body before they are excreted — what’s known as the ‛window of absorption’ — and particle size matters because when you reduce the size of an object, its relative surface area increases. More surface area means an improved rate of dissolution; it’s been demonstrated that reducing the diameter of the particles in pharmaceuticals — a process known as micronization — results in higher dissolution rates and bioavailability.

A formulation of abiraterone acetate, YONSA® (approved by the FDA for treating mCRPC) in combination with methylprednisolone, uses a micronization technique to improve the drug absorption and flexibility of administration options — it is currently the only micronized formulation of abiraterone acetate approved by the FDA. Using a patented micronization process, the drug particles in YONSA® have been reduced to 0.1–0.5 micron, which is up to 200 times smaller than conventional drug particles.

This process allows a lower dose — just 500mg once a day (along with 4mg of methylprednisolone twice daily) — but the increased bioavailability means the drug’s performance is comparable to 1,000mg of another abiraterone acetate, and YONSA® also results in more consistent blood levels and drug absorption. It is important to note, however, that the safety and risk profile of YONSA® is also comparable to 1,000mg of traditional abiraterone acetate. YONSA® must be taken properly — the tablets should not be chewed — and the medication may not be comparable to other formulations of abiraterone acetate, and thus should not be mixed.

YONSA® has also been found to have no food effect — meaning that patients can take YONSA® with or without food, giving them increased flexibility and one less thing to worry about as they battle their disease. Men taking YONSA® do not have to fast, and do not have to take the dose at specific times — they can do so whenever it is convenient.

Metastatic Castration-Resistant Prostate Cancer is a challenging disease to face. Its treatment should be as effective and flexible as possible. For more information about YONSA® and mCRPC, speak with your oncologist, and visit

What is YONSA® (abiraterone acetate)?

YONSA® is a prescription medicine used with methylprednisolone to treat prostate cancer that has spread to other parts of the body and no longer responds to medical or surgical treatment that lowers testosterone.

 It is not known if YONSA® is safe and effective in children.


Who should not take YONSA®(abiraterone acetate)?

YONSA® is not for use in women.

Do not take YONSA® if you are pregnant or may become pregnant. YONSA® may harm your unborn baby.  

Women who are pregnant or who may become pregnant should not touch YONSA® tablets if broken, crushed, or damaged without protection, such as gloves.

What do I need to tell my healthcare provider before taking YONSA®?

Before you take YONSA®, tell your healthcare provider about all of your medical conditions, especially if you: 

  • Have heart problems
  • Have liver problems
  • Have a history of adrenal problems
  • Have a history of pituitary problems
  • Have a partner who is pregnant or may become pregnant.H

Tell your healthcare provider about all the medicines you take, including prescription and over-the counter medicines, vitamins, and herbal supplements. 

How should I take YONSA®?

  • Take YONSA® and methylprednisolone exactly as your healthcare provider tells you. 
  • Take your prescribed dose of YONSA® once a day. Take your prescribed dose of methylprednisolone twice a day. Your healthcare provider may change your dose of YONSA if needed.
  • Do not switch between YONSA® and other medicines that contain abiraterone acetate unless your healthcare provider tells you to. Follow your healthcare provider’s instructions carefully if you are switching between YONSA® and another medicine that contains abiraterone acetate. 
  • Do not take YONSA® and other medicines that contain abiraterone acetate on the same day.
  • Do not stop taking your prescribed dose of YONSA® or methylprednisolone without talking with your healthcare provider first. 
  • Take YONSA® with or without food. 
  • Swallow YONSA® tablets whole with water. Do not crush or chew tablets. 
  • If you miss a dose of YONSA® or methylprednisolone, take your prescribed dose the following day. If you miss more than 1 dose, tell your healthcare provider right away. 
  • If you are receiving gonadotropin-releasing hormone (GnRH) therapy, you should continue your therapy during treatment with YONSA® and methylprednisolone.

Your healthcare provider will do blood tests to check for side effects.

What are the possible adverese effects of YONSA®?

YONSA® may affect fertility in males and may affect your ability to father a child. Talk to your healthcare provider if this is a concern for you

YONSA® may cause serious side effects, including: 

• High blood pressure (hypertension), low blood potassium levels (hypokalemia) and fluid retention (edema). 

Tell your healthcare provider if you get any of the following symptoms:

  • Dizziness
  • Confusion
  • Fast heartbeats
  • Muscle weakness
  • Feel faint or lightheaded
  • Pain in your legs
  • Headache
  • Swelling in your legs or feet

Adrenal problems may happen if you stop taking methylprednisolone, get an infection, or are under stress.

Liver problems. Your healthcare provider will do blood tests to check your liver before and during treatment with YONSA®. Liver failure may occur, which can lead to death. Tell your healthcare provider if you notice any of the following changes:

  • Yellowing of the skin or eyes
  • Darkening of the urine
  • Severe nausea or vomiting

The most common side effects of YONSA® arefatigue, joint swelling or discomfort, edema, hot flush, diarrhea, vomiting, cough, hypertension, dyspnea, urinary tract infection and contusion.

These are not all the possible side effects of YONSA®

Tell your healthcare provider if you have any side effect that bothers you or that does not go away.

Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088 or visit

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