Surgery with or Without Darolutamide in High-risk and/or Locally Advanced Prostate Cancer: The SUGAR (CCAFU-PR2) Phase 2 Trial Rationale and Protocol.

BACKGROUND

High-risk prostate cancer (PCa) patients frequently experience recurrence and progression after radical prostatectomy (RP). Neoadjuvant androgen deprivation therapy (ADT) has not demonstrated a clear oncological benefit and is not currently recommended.

OBJECTIVE

The SUGAR trial is the first phase 2, randomised, controlled, multicentre, noncommercial, open-label study investigating single-agent perioperative darolutamide compared with the standard of care (ie, upfront RP, without neoadjuvant ADT).

DESIGN, SETTING, AND PARTICIPANTS: SUGAR aims to randomise 240 men affected by nonmetastatic PCa, with the major eligibility criteria being International Society of Urological Pathology grade group ≥4, seminal vesicle invasion at magnetic resonance imaging and/or clinically node-positive disease. Patients in the experimental arm will undergo neoadjuvant darolutamide monotherapy, RP, and adjuvant darolutamide, completing 9 mo of treatment.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

The primary endpoint is noncurable recurrence-free survival, an innovative and clinically meaningful measure; the secondary endpoints encompass safety; recurrence-free, metastasis-free, and overall survival; pathological response; and quality of life. A predictive biomarker analysis will also be performed.

RESULTS AND LIMITATIONS

Initial data suggest that intensified neoadjuvant treatment with androgen receptor signalling inhibitors (ARSIs) is associated with a sustained pathological response and may improve outcomes, via tumour downstaging and micrometastasis eradication. ARSI monotherapy could further enhance tolerability.

CONCLUSIONS

SUGAR will provide efficacy and safety information on perioperative darolutamide monotherapy compared with upfront RP, in a contemporary high-risk PCa population undergoing surgery.

PATIENT SUMMARY

The on-going SUGAR clinical trial evaluates 9 mo of darolutamide treatment in addition to radical prostatectomy, in men affected by prostate cancer with specific high-risk characteristics. It investigates whether this hormonal treatment can lower the rates of noncurable recurrences, maintaining a favourable tolerability profile.