Regimen is considered appropriate as part of the standard care of patients; meaningfully improves outcomes (survival, quality of life), tolerability or costs compared to alternatives (recommended by the Disease Site Team and national consensus body e.g. pan-Canadian Oncology Drug Review, pCODR). Recommendation is based on an appropriately conducted phase III clinical trial relevant to the Canadian context OR (where phase III trials are not feasible) an appropriately sized phase II trial. Regimens where one or more drugs are not approved by Health Canada for any indication will be identified under Rationale and Use.
For treatment of metastatic castrate-resistant prostate cancer, as an alternative in patients who cannot tolerate prednisone in ABIRPRED.
|abiraterone||1000 mg||PO||once daily|
(Outpatient prescription in 250 mg or 500 mg tablets)
|dexamethasone||0.5 mg||PO||once daily|
Patients should continue to receive GnRH agonist during abiraterone treatment unless they have had a prior orchiectomy.
- May require increased corticosteroid dosage before, during and after periods of unusual stress such as surgery or trauma.
Doses should be modified according to the protocol by which the patient is being treated. The following recommendations have been adapted from clinical trials or product monographs and may be considered.
Control hypertension and correct hypokalemia before treatment.
Dosage with toxicity
Grade 3 ALT/AST
Grade 3 total bilirubin
Hold; monitor liver function closely until recovery to baseline THEN
Reduce to 500mg/day
Grade 4 ↑ LFTs
ALT/AST > 3 x ULN AND total bilirubin > 2 x ULN (in the absence of biliary obstruction or other causes)
OR ≥ Grade 3 ↑ LFTs after dose modification
OR confirmed pneumonitis/allergic alveolitis
Increased exposure and half-life have been observed in patients with hepatic impairment at baseline; abiraterone has not been studied in patients with moderate or severe hepatic impairment and should not be used (patients with moderate to severe hepatic impairment, active hepatitis, chronic liver disease or ascites were excluded from clinial trials).
Refer to the table above for dose modifications with hepatotoxicity during treatment.
No dose adjustment required for dexamethasone.
|Hepatic Impairment (at baseline)||Dose|
|Mild (Child-Pugh Class A)||No change|
|Moderate (Child-Pugh Class B)||Do not use abiraterone|
|Severe (Child-Pugh Class C)||Do not use abiraterone|
No adjustment required for dexamethasone or abiraterone.
Dosage in the Elderly
No overall differences in effectiveness or adverse effects were seen between elderly and younger patients.
Very common (≥ 50%)
Less common (10-24%)
Uncommon (< 10%),
but may be severe or life-threatening
- Avoid co-administration with CYP2D6 substrates with narrow therapeutic range due to increased risk of toxicity. If must co-administer, consider dose reduction of 2D6 substrate.
- Avoid strong CYP3A4 inducers due to risk of reduced efficacy.
- Avoid strong CYP3A4 inhibitors due to increased risk of toxicity.
- Avoid spironolactone as this may stimulate disease progression.
- Caution when co-administered with drugs that increase risk of myopathy/rhabdomyolysis
- Abiraterone must be taken on an empty stomach. No solid or liquid food should be eaten for at least 2 hours before and at least 1 hour after the dose.
- The tablets should be swallowed whole with a glass of water.
- If an abiraterone dose is missed, skip this and take the next dose as scheduled. Do not double the dose to make up for the missed one.
- Since abiraterone may harm the fetus, women who are pregnant or who may become pregnant should handle abiraterone with protection (e.g. gloves).
- Women who are or may potentially be pregnant (not for use in women)
- Patients who have a hypersensitivity to this drug or any of its components
- Moderate-severe hepatic impairment at baseline
- Severe (grade 4) hepatotoxicity
- Use with caution in patients with cardiovascular disease as they were not included in clinical trials. Increased mineralocorticoid levels from CYP17 inhibition may cause hypertension, hypokalemia and fluid retention. Use with caution in patients whose underlying medical conditions may be affected by these effects.
- Use with caution in patients taking other medications associated with myopathy or rhabdomyolysis (e.g. statins)
- Adrenal insufficiency has been reported in patients taking abiraterone and prednisone. Increased corticosteroid dosage may be required before, during and after the stressful situation.
- Contains lactose and should not be used in patients with hereditary galactose intolerance, severe lactase deficiency or glucose-galactose malabsorption.
- Efficacy may be lower in patients who have been treated previously with ketoconazole for their prostate cancer.
- The safety and efficacy of combination abiraterone and cytotoxic chemotherapy use has not been established.
Treating physicians may decide to monitor more or less frequently for individual patients but should always consider recommendations from the product monograph.
Recommended Clinical Monitoring
- Blood pressure, serum potassium; baseline and monthly
- Cholesterol and triglycerides; baseline, every 2 to 3 months and as clinically indicated
- Liver function tests, bilirubin; baseline, every 2 weeks for the first 3 months and monthly thereafter, or as clinically indicated
- Monitor for adrenal insufficiency; as clinically indicated when dexamethasone is withdrawn, or during periods of infection/stress
- Monitor for mineralocorticoid excess; as clinically indicated if patient continues on abiraterone after stopping dexamethasone
- Clinical toxicity assessment for hypertension, edema, GI, musculoskeletal or steroid side effects, hot flashes, urinary symptoms, cardiac and respiratory toxicity; at each visit
Grade toxicity using the current NCI-CTCAE (Common Terminology Criteria for Adverse Events) version
de Bono JS., Logothetis CJ, Molina A, et al. Abiraterone and increased survival in metastatic prostate cancer. N Engl J Med 2011;364:1995-2005.
Ryan CJ, Smith MR, de Bono JS, et al. Abiraterone in metastatic prostate cancer without previous chemotherapy. N Engl J Med 2013;368(2):138-48.
Venkitaraman R et al. A randomised phase 2 trial of dexamethasone versus prednisolone in castration-resistant prostate cancer. Eur Urol. 2015 Apr; 67(4)673-9.
July 2018 updated regimen abstract into a full regimen monograph
A Regimen Abstract is an abbreviated version of a Regimen Monograph and contains only top level information on usage, dosing, schedule, cycle length and special notes (if available). It is intended for healthcare providers and is to be used for informational purposes only. It is not intended to constitute or be a substitute for medical advice, and all uses of the Regimen Abstract are subject to clinical judgment. Such information is provided on an “as-is” basis, without any representation, warranty, or condition, whether express, or implied, statutory or otherwise, as to the information’s quality, accuracy, currency, completeness, or reliability, and Cancer Care Ontario disclaims all liability for the use of this information, and for any claims, actions, demands or suits that arise from such use.
Information in regimen abstracts is accurate to the extent of the ST-QBP regimen master listings, and has not undergone the full review process of a regimen monograph. Full regimen monographs will be published for each ST-QBP regimen as they are developed.
Refer to the New Drug Funding Program or Ontario Public Drug Programs websites for the most up-to-date public funding information.
The information set out in the drug monographs, regimen monographs, appendices and symptom management information (for health professionals) contained in the Drug Formulary (the "Formulary") is intended for healthcare providers and is to be used for informational purposes only. The information is not intended to cover all possible uses, directions, precautions, drug interactions or adverse effects of a particular drug, nor should it be construed to indicate that use of a particular drug is safe, appropriate or effective for a given condition. The information in the Formulary is not intended to constitute or be a substitute for medical advice and should not be relied upon in any such regard. All uses of the Formulary are subject to clinical judgment and actual prescribing patterns may not follow the information provided in the Formulary.
The format and content of the drug monographs, regimen monographs, appendices and symptom management information contained in the Formulary will change as they are reviewed and revised on a periodic basis. The date of last revision will be visible on each page of the monograph and regimen. Since standards of usage are constantly evolving, it is advised that the Formulary not be used as the sole source of information. It is strongly recommended that original references or product monograph be consulted prior to using a chemotherapy regimen for the first time.
Some Formulary documents, such as the medication information sheets, regimen information sheets and symptom management information (for patients), are intended for patients. Patients should always consult with their healthcare provider if they have questions regarding any information set out in the Formulary documents.
While care has been taken in the preparation of the information contained in the Formulary, such information is provided on an “as-is” basis, without any representation, warranty, or condition, whether express, or implied, statutory or otherwise, as to the information’s quality, accuracy, currency, completeness, or reliability.
CCO and the Formulary’s content providers shall have no liability, whether direct, indirect, consequential, contingent, special, or incidental, related to or arising from the information in the Formulary or its use thereof, whether based on breach of contract or tort (including negligence), and even if advised of the possibility thereof. Anyone using the information in the Formulary does so at his or her own risk, and by using such information, agrees to indemnify CCO and its content providers from any and all liability, loss, damages, costs and expenses (including legal fees and expenses) arising from such person’s use of the information in the Formulary.