Castration using low-dose abiraterone plus prednisone without LHRH therapy for prostate cancer needing hormonal intensification

Castration With Abiraterone 250 mg Without LHRH Analogs or Blockers in Patients With Prostate Cancer Requiring Hormonal Intensification (Multicenter Phase 2)

This tests whether taking abiraterone 250 mg with food plus prednisone can lower testosterone to castration levels within 30 days in men with prostate cancer who need hormonal intensification without using LHRH analogs.

Quick facts

• Phase: Phase 2
• Study type: Interventional
• Enrollment: 60 (estimated)
• Ages: 18 Years and up
• Sex: Male
• Sponsor: SMED Clinical Research (Academic / other)
• Drugs / interventions: prednisone
• Locations: 3 sites (Buenos Aires and 2 other locations)
• Trial ID: NCT07299292 on ClinicalTrials.gov

What this trial studies

This is a phase 2, prospective, open-label, multicenter single-cohort trial giving abiraterone 250 mg with food plus daily prednisone to men eligible for hormonal intensification while withholding standard LHRH analogs for the first 30 days. Eligible patients include high/very-high risk localized cases planned for radiotherapy and metastatic hormone-sensitive patients planned for doublet or triplet therapy, all without prior ADT. The primary endpoint is the proportion achieving serum testosterone ≤50 ng/dL at Day 30 (with sensitivity analysis at ≤20 ng/dL) and time to castration; secondary endpoints include early PSA changes and safety monitoring for hypertension, hypokalemia, hepatotoxicity, fluid retention, and adrenal insufficiency. Visits include screening, Day 0 start of therapy, Day 30 endpoint evaluation, and safety follow-up to Day 60 at participating centers in Argentina, Mexico, and Bolivia.

Who should consider this trial

Good fit: Men aged ≥18 with histologically confirmed prostate adenocarcinoma who are candidates for hormonal intensification (high/very-high risk for radiotherapy or mHSPC planned for abiraterone doublet/triplet), with no prior ADT, ECOG 0–2, adequate labs, and treated at a participating center are ideal candidates.

Not a fit: Patients with prior ADT, uncontrolled hypertension, moderate-to-severe hepatic impairment, refractory hypokalemia, known hypersensitivity to abiraterone or prednisone, or on contraindicated interacting medications are unlikely to benefit from this regimen.

Why it matters

Potential benefit: If successful, this approach could provide a faster, oral way to achieve castration-level testosterone without injectable LHRH therapy, potentially accelerating access to intensified treatment and reducing costs.

How similar studies have performed: Some pharmacokinetic and small clinical studies indicate that abiraterone 250 mg taken with food can achieve similar drug exposure and testosterone suppression to standard dosing, but replacing LHRH analogs with low-dose abiraterone alone has not been widely validated in large trials.

Eligibility criteria

Inclusion Criteria:

* Age ≥18 years.
* Histologically confirmed prostate adenocarcinoma.
* Treated at Hospital Durand (Argentina) or Instituto Oncológico del Oriente Boliviano (Bolivia).
* Indicated for hormonal intensification (high/very high risk candidates for RT, or mHSPC for doublet/triplet).
* No prior ADT.
* ECOG 0-2; adequate hepatic/renal function; K+ ≥3.5 mmol/L; controlled BP.

Exclusion Criteria:

* Hypersensitivity to ABI/prednisone; moderate-severe hepatic impairment; uncontrolled hypertension; refractory hypokalemia.
* Concurrent therapy with strongly contraindicated/inducing drugs affecting ABI levels without possibility of adjustment.

Where this trial is running

Buenos Aires and 2 other locations

• Hospital Carlos A Durand — Buenos Aires, Argentina (Recruiting)
• Hospital San José — Hermosillo, Spain (Not_yet_recruiting)
• Instituto Oriente Boliviano — Santa Cruz de la Sierra, Spain (Recruiting)

Conditions Prostate Cancer; prostate cancer; castration; abiraterone; hormonal intensification