Actively Recruiting
The SUGAR Study; SBRT and Relugolix) for Prostate Cancer
Led by Yale University · Updated on 2026-05-11
60
Participants Needed
3
Research Sites
198 weeks
Total Duration
On this page
Sponsors
Y
Yale University
Lead Sponsor
P
Pfizer
Collaborating Sponsor
AI-Summary
What this Trial Is About
The goal of this clinical trial is to measure the toxicity and effectiveness of the following treatments for cFIR/cgUIR prostate cancer patients. Stereotactic body radiotherapy (SBRT) alone or Stereotactic body radiotherapy (SBRT) combined with Ultrashort GNRH Antagonist called Relugolix (an oral drug). Treatments will be randomly assigned to study patients. The main questions it aims to answer are the following: 1. Whether the proportion of men who undergo SUGAR have superior rate of attaining PSA nadir of \<= 0.2 compared to SBRT alone, and 2. Whether SUGAR is superior to historical rates of minimal clinically important decline (MCID) in sexual and hormonal function at 6 months for patients undergoing 6 months of androgen deprivation therapy (ADT) Men aged 18+ with cFIR/cgUIR will be enrolled. Specifically, patients must meet one of the following 2 criteria: 1) Gleason score must be Gleason 3+4 with a PSA \< 20 ng/mL, or 2) Gleason 6 (3+3) and PSA \> 10 ng/mL and \< 20 ng mL.
CONDITIONS
Official Title
The SUGAR Study; SBRT and Relugolix) for Prostate Cancer
Who Can Participate
Eligibility Criteria
You may qualify if you...
- Signed and dated informed consent form
- Willingness to comply with all study procedures and be available for the study duration
- Histologically or cytologically confirmed adenocarcinoma of the prostate
- Assigned male at birth, age 18 or older; female identifying transgender or gender fluid allowed if they have a prostate and no testosterone suppressing therapy
- Serum testosterone above 100 ng/dL at screening
- Serum PSA above 0.2 ng/mL at screening
- Able to swallow pills and take medication orally, willing to follow daily medication if assigned to experimental arm
- Use effective contraception during radiotherapy and for 4 months after last dose if of reproductive potential
- Agree to follow lifestyle considerations during the study
- Clinical favorable intermediate risk prostate cancer: Gleason 3+4 with PSA under 20 ng/mL, or Gleason 3+3 with PSA between 10 and 20 ng/mL
- Decipher genomic classifier score of 0.6 or higher indicating high genomic risk
- Prostate volume 80 cc or less by MRI, ultrasound, or physician attestation within 120 days
You will not qualify if you...
- Current use of medications that cause QT prolongation
- Known allergy to relugolix
- Treatment with another investigational drug or intervention for prostate cancer within 30 days of enrollment
- History of ulcerative colitis or other inflammatory bowel disease
- Diagnosis of connective tissue disease such as lupus, scleroderma, or dermatomyositis
- Medical contraindications or intolerance to GnRH antagonist therapy or SBRT
- History of long QT syndrome
- ECG abnormalities including recent Q-wave infarction, QTc over 470 msec, or congenital long QT syndrome
- History of surgical castration
- Prior prostate cancer treatment with surgery or prostate-directed radiotherapy
AI-Screening
AI-Powered Screening
Complete this quick 3-step screening to check your eligibility
Trial Site Locations
Total: 3 locations
1
Yale Cancer Center
New Haven, Connecticut, United States, 06520
Actively Recruiting
2
Memorial Sloan Kettering Cancer Center
New York, New York, United States, 10017
Actively Recruiting
3
University of Washington
Seattle, Washington, United States, 98109
Actively Recruiting
Research Team
C
Camalene Chrysostoum
CONTACT
T
Tara McPartland
CONTACT
How is the study designed?
Study Type
INTERVENTIONAL
Masking
NONE
Allocation
RANDOMIZED
Model
PARALLEL
Primary Purpose
TREATMENT
Number of Arms
2
Not the Right Trial for You?
Explore thousands of other clinical trials that might be a better match.
Sign up to get personalized trial recommendations delivered to your inbox.
Already have an account? Log in here