• Oncology Clinical Trials
• Reproductive Cancers

• Oncology
• Oncology Clinical Trials
• Reproductive Cancers

Adjuvant androgen deprivation therapy (ADT), including a luteinizing hormone-releasing hormone analogue (LHRHA) for 2 to 3 years, is the standard of care before, during, and after radiotherapy for patients with localized prostate cancer at high risk of recurrence. Although outcomes in patients receiving long-term ADT (18 to 36 months) are superior to those seen in patients receiving 6 months of treatment, the optimal regimen remains unclear.

Scott Williams, PhD, Peter MacCallum Cancer Centre, Melbourne, Victoria, Australia, presented the design and objectives for a phase 3 trial of Enzalutamide in Androgen Deprivation Therapy with Radiation Therapy for High Risk, Clinically Localized, Prostate Cancer [ENZARAD; Australian New Zealand Clinical Trials Registry ACTRN12614000126617; Williams S et al. Ann Oncol. 2014], which is currently enrolling patients.

Enzalutamide is a new second-generation androgen receptor inhibitor that improves survival in metastatic castration-resistant prostate cancer; it is more potent and binds with a higher affinity to androgen receptors than do conventional nonsteroidal antiandrogens (NSAAs).

ENZARAD is an open-label intergroup trial open to adult men who have localized prostate cancer that is of high risk of recurrence and who are suitable for external beam radiation therapy (EBRT) with the intent to cure. Participants are stratified by Gleason score (7 vs 8 to 10), clinical stage (T1 to T2 vs T3 to T4), prostate-specific antigen (PSA) levels ≥ 10 ng/mL or ≥ 20 ng/mL, and study site. Patients are then randomized 1:1 to either enzalutamide (160 mg, daily) for 24 months or conventional NSAAs for 6 months. All participants will receive LHRHA for 24 months and EBRT (78 Gy/39 F) starting after week 16.

The primary study end point is overall survival. Secondary end points include cause-specific survival, PSA progression-free survival, clinical progression-free survival, time to subsequent hormonal therapy, health-related quality of life, adverse events, and health outcomes relative to cost. A tertiary objective is to identify biomarkers that are prognostic or predictive of response to treatment. Study assessments will be conducted at baseline; weeks 4, 12, 16, 20, and 24; then every 3 to 4 months until year 5, every 6 months until year 7, and annually thereafter. Computed tomography and magnetic resonance imaging and bone scan will be performed at baseline, then as clinically indicated. The tertiary objective will be assessed through archival tumor tissue and data from fasting blood collected at baseline, 24 weeks, 5 years, and first evidence of progression.

This study opened for recruitment in March 2014, with a planned duration of recruitment of 2 years. As of September 27, 2014, 9 sites were open to recruitment; 84 patients had been screened; and 20 patients had been randomized to treatment. Sites continue to be opened for recruitment in Australia, New Zealand, Ireland, the United Kingdom, and Europe.

Additional information on this study is available by e-mail (enzarad{at}ctc.usyd.edu.au) or from the study website: http://www.anzup.org.au/.

• © 2014 MD Conference Express®