Description of Relugolix Use in Patients With Prostate Cancer Within the VHA

Description of Relugolix Use in Patients With Prostate Cancer: An Analysis of National Veterans Affairs Health Care Network Data

The purpose of this real-world study is the learn about the demographics and clinical characteristics of patients with prostate cancer who initiated relugolix

Study Overview

• Status: Completed
• Conditions: Prostate Cancer
• Intervention / Treatment: Drug: Relugolix

Detailed Description

Prostate cancer (PC) is the most common cancer and the second leading cause of cancer death among men in the United States. Androgen deprivation therapy (ADT) such as injectable luteinizing hormone-releasing hormone (LHRH) agonists (e.g., leuprolide) is the standard of care for PC patients. ADT treatment can suppress testosterone level to castrate level and delay the progression of the disease.

Relugolix is a recently approved oral GnRH antagonist. While the introduction of relugolix has offered a unique opportunity for patients with PC, it's vital to understand how it is being used in real-world.

• Study Type: Observational
• Enrollment (Actual): 507

Contacts and Locations

Study Locations

• United States
  • New York
    • New York, New York, United States, 10001
      • Pfizer

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

• Sampling Method: Non-Probability Sample

Study Population

Men who are part of this study initiated relugolix as part of their usual treatment for PC

Description

Inclusion Criteria:

• Male with ≥ 1 diagnosis for PC
• Had ≥ 2 prescriptions of relugolix on or after the first observed PC diagnosis.
• Index date: the initiation date of relugolix
• At least 18 years old at the index date

Exclusion Criteria:

• had surgical castration (bilateral orchiectomy) any time before the index date

Study Plan

How is the study designed?

Number of groups / cohorts

1

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
Relugolix patients; Patients who have initiated relugolix	Drug: Relugolix; relugolix

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Number of Participants According to Geographic Region	The number of participants according to geographic regions of the United States (South, West, Northeast and Midwest) as documented during baseline period were reported in this outcome measure. Baseline period was 1 year prior to index date; index date was the initiation date of relugolix (anytime between 18-Dec-2020 to 31-Dec-2023) on or after the first observed prostate cancer diagnosis.	Baseline period = Up to 1 year prior to index date; available data observed retrospectively over 178 days in this study
Number of Participants According to Index Year	Number of participants according to index year (2020, 2021, 2022 and 2023) were reported in this outcome measure. The index date was defined as the initiation date of relugolix (anytime between 18-Dec-2020 to 31-Dec-2023) on or after the first observed prostate cancer diagnosis.	At Index date (anytime between 18-Dec-2020 to 31-Dec- 2023 [approximately 3 years]; available data observed retrospectively over 178 days in this study
Time From First Observed Prostate Cancer Diagnosis Date to the Index Date	Time from the first observed prostate cancer date to the index date was evaluated. All data available prior to the index date were used. The index date was defined as the initiation date of relugolix (anytime between 18-Dec-2020 to 31-Dec-2023) on or after the first observed prostate cancer diagnosis. Participants with a diagnosis of prostate cancer between 01-Jan-2006 to 31-Dec-2023 were considered.	From prostate cancer diagnosis to index date (approximately maximum up to 18 years); available data observed retrospectively over 178 days in this study
Number of Participants According to Type of Previous Treatments Received	Number of participants according to treatments received previously such as pain medication, androgen receptor pathway inhibitor, androgen deprivation therapy, chronic oral corticosteroid use, non-steroidal anti-androgen, radiotherapy, olaparib, prostatectomy and chemotherapy in the baseline period were reported in this outcome measure. Baseline period was 1 year prior to index date; index date was the initiation date of relugolix (anytime between 18-Dec-2020 to 31-Dec-2023) on or after the first observed prostate cancer diagnosis. One participant could have received more than 1 treatment.	Baseline period = Up to 1 year prior to index date; available data observed retrospectively over 178 days in this study
Number of Participants According to Metastasis Status	Number of participants according to metastasis status (metastatic prostate cancer and non-metastatic prostate cancer) were reported in this outcome measure. Metastatic prostate cancer was defined as having evidence of during the baseline period or within 90 days after the index date. Baseline period was 1 year prior to index date; index date was the initiation date of relugolix (anytime between 18-Dec-2020 to 31-Dec-2023) on or after the first observed prostate cancer diagnosis.	Baseline period = Up to 1 year prior to index date or within 90 days after the index date; available data observed retrospectively over 178 days in this study
Number of Participants According to Site of Metastasis	Number of participants with a metastatic diagnosis at the sites: bone only, node only, bone and node, viscera and other (urinary organs, genital organs, skin, kidney, adrenal, brain, spinal, and other nervous system), were reported among participants with metastatic prostate cancer. Metastatic prostate cancer was defined as having evidence of metastasis any time prior to the index date or within 90 days after the index date. Baseline period was 1 year prior to index date; index date was the initiation date of relugolix (anytime between 18-Dec-2020 to 31-Dec-2023) on or after the first observed prostate cancer diagnosis.	Baseline period = Up to 1 year prior to index date or within 90 days after the index date; available data observed retrospectively over 178 days in this study
Number of Participants According to Androgen Deprivation Therapy (ADT) Status	ADT naïve was defined as having no records of any systemic ADT ever based on all available data prior to the index date (i.e., including baseline period data and any available data prior to the baseline period). Systemic ADT included luteinizing hormone-releasing hormone (LHRH) agonists and gonadotropin-releasing hormone (GnRH) antagonists (i.e., degarelix, relugolix, goserelin, histrelin, leuprolide, triptorelin). ADT experienced was defined as having any records of systemic ADT based on all available data prior to the index date (i.e., including baseline period data and any available data prior to the baseline period). Baseline period was 1 year prior to index date; index date was the initiation date of relugolix (anytime between 18-Dec-2020 to 31-Dec-2023) on or after the first observed prostate cancer diagnosis.	Any time prior to index date including baseline period (approximately maximum up to 18 years); available data observed retrospectively over 178 days in this study
Prostate-Specific Antigen (PSA) Value at 180 Days Prior to Index Date	The index date was defined as the initiation date of relugolix (anytime between 18-Dec-2020 to 31-Dec-2023) on or after the first observed PC diagnosis.	180 days prior to Index date; data observed retrospectively over 178 days in this study
Testosterone Value at 180 Days Prior to Index Date	The index date was defined as the initiation date of relugolix (anytime between 18-Dec-2020 to 31-Dec-2023) on or after the first observed PC diagnosis.	180 days prior to Index date; data observed retrospectively over 178 days in this study
Mean National Cancer Institute (NCI) Charlson Comorbidity Index (CCI) Score	CCI based on various comorbid conditions such as myocardial infarction, congestive heart failure, peripheral vascular disease, cerebrovascular disease, dementia, chronic obstructive pulmonary disease, rheumatologic disease, peptic ulcer disease, mild liver disease, diabetes (mild to moderate), diabetes + complications, hemiplegia or paraplegia, renal disease, any malignancy (lymphoma and leukemia), moderate/severe liver disease, metastatic solid tumor, and acquired immune deficiency syndrome (AIDS) were reported. CCI score range was from 0 to 14, where "0"= low comorbid condition and "14"= high comorbid condition, higher scores indicated more comorbidity. Baseline period was 1 year prior to index date; index date was the initiation date of relugolix (anytime between 18-Dec-2020 to 31-Dec-2023) on or after the first observed prostate cancer diagnosis.	Baseline period = Up to 1 year prior to index date or within 90 days after the index date; available data observed retrospectively over 178 days in this study
Number of Participants According to Comorbidities	Number of participants according to comorbidities (hypertension, hyperlipidemia, diabetes, major adverse cardiovascular event, depression, congestive heart failure, sexual dysfunction, chronic obstructive pulmonary disease, anxiety, cognitive impairment, urinary tract infection, myocardial infarction, arrhythmia, stroke, acute coronary syndrome, angina pectoris, inflammatory bowel disease, hot flashes) were reported in this outcome measure. Baseline period was 1 year prior to index date; index date was the initiation date of relugolix (anytime between 18-Dec-2020 to 31-Dec-2023) on or after the first observed prostate cancer diagnosis. One participant could have more than one comorbidity.	Baseline period = Up to 1 year prior to index date or within 90 days after the index date; available data observed retrospectively over 178 days in this study

Collaborators and Investigators

• Sponsor: Pfizer
• Investigators: Study Director: Pfizer CT.gov Call Center, Pfizer

Publications and helpful links

General Publications

• Freedland SJ, Ramaswamy K, Kavati A, Gao W, Razo JF, Cole M, Li B, Yang H, Guo T, Chen G, McKay RR. Retrospective Analysis of Racial Differences in Treatment Patterns and Prostate-Specific Antigen Responses Among Patients with Prostate Cancer Treated with Relugolix in the Veterans Health Administration. Adv Ther. 2025 Dec;42(12):6278-6294. doi: 10.1007/s12325-025-03390-6. Epub 2025 Nov 1.

Helpful Links

• To obtain contact information for a study center near you, click here.

Study record dates

Study Major Dates

• Study Start (Actual): June 19, 2024
• Primary Completion (Actual): December 13, 2024
• Study Completion (Actual): December 13, 2024

Study Registration Dates

• First Submitted: May 23, 2024
• First Submitted That Met QC Criteria: June 12, 2024
• First Posted (Actual): June 17, 2024

Study Record Updates

• Last Update Posted (Actual): December 11, 2025
• Last Update Submitted That Met QC Criteria: December 9, 2025
• Last Verified: November 1, 2025

More Information

Terms related to this study

• Keywords: Relugolix
• Additional Relevant MeSH Terms: Urogenital Diseases; Genital Diseases; Genital Neoplasms, Male; Urogenital Neoplasms; Neoplasms by Site; Neoplasms; Genital Diseases, Male; Prostatic Diseases; Male Urogenital Diseases; Prostatic Neoplasms; Physiological Effects of Drugs; Hormones, Hormone Substitutes, and Hormone Antagonists; Hormone Antagonists; Androgen Antagonists; relugolix
• Other Study ID Numbers: C4751009; VHA Study (Other Identifier: Alias Study Number)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO
• IPD Plan Description: Pfizer will provide access to individual de-identified participant data and related study documents (e.g. protocol, Statistical Analysis Plan (SAP), Clinical Study Report (CSR)) upon request from qualified researchers, and subject to certain criteria, conditions, and exceptions. Further details on Pfizer's data sharing criteria and process for requesting access can be found at: https://www.pfizer.com/science/clinical_trials/trial_data_and_results/data_requests.