A Study to Compare the Results of FGFR Testing by Either CtDNA Blood Testing or Standard Tumor Tissue Testing

Recruiting

• Conditions: Metastatic Bladder Cancer; Metastatic Urothelial Carcinoma
• Interventions: Genetic: FGFR Testing

• Registration Number: NCT06129084
• Lead Sponsor: Bernie Eigl

Brief Summary

A new drug, erdafitinib, became available for some patients with bladder cancer that has spread to other organs. To qualify, patients must have specific genetic changes in their tumors. Currently, doctors use tumor tissue samples to check for these genetic changes, but these samples might not accurately reflect the current state of the patient's cancer.

In this study, Investigators will test the patient's blood for these genetic changes in addition to the tumor tissue samples. It is thought that the blood test will give a more accurate result.

Investigators hope this study will help to find out if more patients can benefit from erdafitinib than the ones identified by tissue testing only.

Detailed Description

Recently, the first targeted therapy for patients with metastatic urothelial cancer (mUC) received approval, i.e. erdafitinib. Erdafitinib is a pan-FGFR small molecule inhibitor. Approximately twenty percent of mUC patients' tumors harbor qualifying alterations in FGFR2 or FGFR3. Currently, standard testing uses archival tumor tissue. However, this type of testing may not be representative of a patient's clinically dominant tumor clone at the time of treatment initiation due to temporal and spatial biopsy bias of archival tissue testing.

In this study, patients will undergo circulating tumor DNA testing, in addition to conventional tissue testing, for treatment eligibility. Investigators hypothesize that blood-based ctDNA testing will provide a more accurate assessment of somatic FGFR status than same patient archival primary tissue.

This study's objectives are:

Objective 1 (Primary): To evaluate the diagnostic value of ctDNA testing against the "gold standard" of tissue testing.

Objective 2 (Secondary): To evaluate whether ctDNA may be a superior predictive marker by identifying actionable FGFR alterations that are currently missed on tissue assays.

Procedures:

* Medical history will be reviewed, including all previous anti-cancer treatments.

* A blood sample will be collected for ctDNA testing at the time of screening for FGFR alterations and at progression under erdafitinib therapy. Test results will be compared to archival tissue testing.

Study Timeline

• Study Start: 2021-01-11
• Study First Submitted: 2023-11-08
• Study First Submitted QC: 2023-11-08
• Study First Posted: 2023-11-13
• Status Verified: 2024-10
• Last Update Submitted: 2024-10-22
• Last Update Posted: 2024-10-24
• Primary Completion: 2025-03-01
• Study Completion: 2025-05-01

Recruitment & Eligibility

• Status: RECRUITING
• Sex: All
• Target Recruitment: 260

Inclusion Criteria

• Patients with metastatic bladder cancer who are about to undergo tissue testing for FGFR mutations and who have blood samples drawn during the management of their disease are eligible to be included in this analysis.

Exclusion Criteria

• Metastatic bladder cancer patients who will not have tissue sent for FGFR testing will be excluded from this study.

Study & Design

• Study Type: OBSERVATIONAL
• Study Design: Not specified

Arm && Interventions

Group	Intervention	Description
Metastatic Bladder Cancer	FGFR Testing	Patients with metastatic bladder cancer who will have archival tissue sent for FGFR testing.

Primary Outcome Measures

Name	Time	Method
To evaluate the diagnostic value of ctDNA testing against standard tissue testing	For the primary objective, a single blood sample is collected at the time of screening for treatment eligibility	Investigators will evaluate ctDNA as a diagnostic test against the de facto gold standard of tissue testing.

Secondary Outcome Measures

Name	Time	Method
To evaluate whether ctDNA may be a superior predictive marker by identifying actionable FGFR mutations that are currently missed on tissue assays	For this secondary objective, a single blood sample is collected at the time of screening for treatment eligibility	To quantify the additional value of ctDNA testing, Investigators will calculate the percentage of eligible patients based on ctDNA testing among conventional testing ineligible or "negative" patients.

Trial Locations

Locations (7)

Arthur J.E Child Comprehensive Cancer Centre; 🇨🇦 Calgary, Alberta, Canada

Cross Cancer Institute; 🇨🇦 Edmonton, Alberta, Canada

BC Cancer Agency; 🇨🇦 Vancouver, British Columbia, Canada

London Health Sciences Centre; 🇨🇦 London, Ontario, Canada

Ottawa Hospital Research Institute; 🇨🇦 Ottawa, Ontario, Canada

Princess Margaret Cancer Centre; 🇨🇦 Toronto, Ontario, Canada

CHU de Québec-Université Laval; 🇨🇦 Québec City, Quebec, Canada