Bicalutamide 30mg Dosage and Treatment Duration for Prostate Cancer
The standard dosage of bicalutamide is 50mg once daily when used in combination therapy with LHRH agonists for advanced prostate cancer, or 150mg once daily when used as monotherapy for locally advanced non-metastatic prostate cancer. The 30mg dosage is not a standard recommended dose for prostate cancer treatment. 1, 2
Standard Dosing Regimens
- Bicalutamide 50mg once daily is the recommended dose when used in combination with a luteinizing hormone-releasing hormone (LHRH) agonist or surgical castration for advanced prostate cancer 2
- Bicalutamide 150mg once daily is recommended as monotherapy for early (localized or locally advanced) non-metastatic prostate cancer 2
- Treatment duration is typically continuous until disease progression or unacceptable toxicity 1
Evidence for Efficacy
- At 50mg daily dosing, bicalutamide combined with LHRH agonists has demonstrated equivalent efficacy to flutamide (250mg three times daily) combinations in advanced prostate cancer 3
- At 150mg daily dosing as monotherapy, bicalutamide has shown similar survival outcomes to castration in patients with locally advanced non-metastatic disease 4
- Clinical trials comparing enzalutamide (160mg/day) to bicalutamide (50mg/day) in castration-resistant prostate cancer showed superior progression-free survival with enzalutamide (15.7 vs 5.8 months) 5
Pharmacokinetics Considerations
- Bicalutamide has a long plasma elimination half-life of approximately 1 week 2
- The drug accumulates about 10-fold in plasma during daily administration 2
- Steady-state concentrations increase linearly with doses up to 50mg, but nonlinearly at higher doses 2
- The active (R)-enantiomer has a much longer half-life than the inactive (S)-enantiomer, resulting in 100-fold higher steady-state concentrations 2
Clinical Considerations for Dosing
- Dose-ranging studies have evaluated bicalutamide at doses from 10mg to 600mg daily, with increasing evidence of activity up to 200mg 6
- Doses higher than 200mg show evidence of nonlinearity in plasma concentrations, suggesting limited additional benefit with further dose escalation 6
- No dose adjustment is required for renal impairment or mild-to-moderate hepatic impairment 2
- Slower elimination has been observed in patients with severe hepatic impairment 2
Side Effects and Monitoring
- Common side effects include breast pain and gynecomastia 3
- Bicalutamide has not been causally associated with interstitial pneumonitis or visual adaptation problems seen with other antiandrogens 3
- At 50mg daily, bicalutamide causes less diarrhea than flutamide 750mg daily 3
- Hepatic function changes are generally transient and resolve during therapy or after treatment withdrawal 3
- Regular monitoring of liver function tests is recommended 2
Quality of Life Considerations
- Bicalutamide monotherapy better preserves sexual interest and physical capacity compared to castration 4
- This quality of life benefit should be balanced against potential efficacy differences when selecting treatment 5
Important Caveats
- The 30mg dose is not a standard recommended dose in any major guidelines for prostate cancer treatment 5
- If considering a lower dose than standard recommendations, be aware that dose-response relationships suggest potentially reduced efficacy 6
- Enzalutamide has demonstrated superior progression-free survival compared to bicalutamide in castration-resistant prostate cancer, though bicalutamide may still be considered due to different side effect profiles and cost considerations 5