abiraterone vs exemestane
PlainMeds reviewed this comparison against our methodology in August 2026. It places FDA and CMS record fields side by side, without recommending either medication.
Side-by-side comparison of abiraterone and exemestane. Data from FDA drug databases (Orange Book, NDC Directory, recalls, shortages) covering 20,000+ approved drugs, plus CMS pricing; see our methodology.
Zytiga
Aromasin
Abiraterone (Zytiga) is a medicine used with prednisone to treat prostate cancer that has spread. It works by lowering the amount of androgen your body makes.
Exemestane is a medicine used to treat breast cancer in women after menopause. It lowers estrogen levels in the body.
Abiraterone is used to treat prostate cancer that has spread to other parts of the body. It is for cancers that are castration-resistant, meaning they no longer respond to hormone therapy alone. It is also used for high-risk castration-sensitive prostate cancer. You will take this medicine with prednisone.
Exemestane is used to treat breast cancer in women who have gone through menopause. It is for women with estrogen-receptor positive early breast cancer who have already taken tamoxifen for 2 to 3 years. It is also used for advanced breast cancer that has gotten worse after tamoxifen treatment.
Abiraterone blocks an enzyme called CYP17, which your body needs to make androgens. Androgens can help prostate cancer grow. By blocking this enzyme, abiraterone lowers androgen levels and slows cancer growth.
Exemestane blocks a substance called aromatase in your body. Aromatase makes estrogen. By blocking aromatase, exemestane lowers the amount of estrogen, which can slow the growth of breast cancer cells.
- • Feeling tired
- • Joint pain
- • High blood pressure
- • Feeling sick to your stomach
- • Swelling
- • Hot flashes
- • Feeling tired
- • Joint pain
- • Headache
- • Trouble sleeping
- Death 1,390
- Fatigue 1,023
- Hot Flush 678
- Asthenia 562
- Disease Progression 561
- Fatigue 2,174
- Malignant Neoplasm Progression 1,772
- Arthralgia 1,678
- Nausea 1,675
- Diarrhoea 1,661
Abiraterone can cause problems with mineralocorticoid excess, like high blood pressure, low potassium, and fluid retention. If you have heart problems, your doctor will monitor you closely. This medicine can also cause liver problems, which can be severe. Your doctor will check your liver function regularly. Do not take abiraterone with radium Ra 223 dichloride. Abiraterone can harm an unborn baby, so men should use effective birth control if their partner can get pregnant.
Exemestane can cause bone thinning (lower bone mineral density). Your doctor should check your vitamin D levels before you start taking exemestane. If you could get pregnant, exemestane can harm an unborn baby. Use effective birth control while taking this medicine.
Abiraterone can cause harm to an unborn baby. Men who are taking abiraterone should use effective birth control during treatment and for 3 weeks after the last dose if their partner is able to get pregnant. It is not known if abiraterone passes into breast milk.
Exemestane can harm an unborn baby. If you are able to become pregnant, you must use effective birth control while taking exemestane and talk to your doctor. Do not breastfeed while taking exemestane and for 1 month after the last dose.
How to Read This abiraterone vs exemestane Comparison
abiraterone is classified in the CYP17 Inhibitor drug class, while exemestane sits within the Aromatase Inhibitor (Steroidal) class. Drugs from different classes work through distinct mechanisms, so a head-to-head comparison illustrates trade-offs rather than equivalence. Both drugs are prescription-only, so a licensed provider must authorize use.
Adverse event totals above are pulled from the FDA's Adverse Event Reporting System (FAERS). For these top-ranked reactions alone, abiraterone has 4,214 submissions while exemestane has 8,960. Those figures reflect cumulative reporting volume, not per-patient risk, so older, widely dispensed drugs typically look worse on count alone. No direct interaction between these two drugs is listed in our FDA-derived dataset, though co-prescription still warrants pharmacist review. Serious warnings, pregnancy guidance, and contraindications can differ even when indications overlap.
A table cannot represent individual circumstances. Data here is sourced from FDA Structured Product Labels (SPL) and FAERS, both of which update as manufacturers and clinicians submit new information. This registry does not provide medical, treatment, substitution, or medication-change directions for abiraterone or exemestane.
Registry boundary: This comparison displays source-record fields and does not provide individualized medical direction.