Stereotactic Ablative Radiation for Oligo-Progression of Urothelial Cancer

Study Overview
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Brief Summary
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To evaluate the benefit of SAbR for oligo-progressive metastatic urothelial cancer.

Detailed Description
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Oligo-progressive urothelial cancer with limited disease burden and progression on an anti-PD-1/L1 immune checkpoint inhibitor.

Official Title
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A Phase II Trial of Stereotactic Ablative Radiation (SAbR) for Urothelial Cancer Patients With Progression While on Anti-PD-1/PD-L1 Immunotherapy

Conditions
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Urothelial Cancer

Intervention / Treatment
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* Radiation: Stereotactic Ablative Radiation


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients must be at least 18-years-old ECOG performance status 0-2 Patients must have pathology-proven metastatic urothelial carcinoma, with tissue sampling of at least the primary tumor. Tissue sampling of each presumed metastatic site is not necessary, provided that the patient already has a confirmed diagnosis of urothelial cancer. Patients must be on immune checkpoint inhibitor therapy with radiographic scans to verify oligo-progression of at least one and ≤ 6 sites of disease per RECIST 1.1. Any of the currently FDA-approved PD-1/PD-L1 inhibitors are allowed. These include pembrolizumab, nivolumab, atezolizumab, avelumab, and durvalumab. At least 1 metastatic lesion must show stable disease, partial response or complete response per RECIST 1.1. Patients must be able to understand and willing to sign written informed consent. Patients must have acceptable tolerability of ongoing therapy as decided by the treating medical oncologist. Patients must have a desire to continue ongoing therapy. Women of child-bearing potential and men must agree to use adequate contraception (hormonal or barrier method of birth control; abstinence) prior to study entry, for the duration of study participation, and for 90 days following completion of therapy. A female of child-bearing potential is any woman (regardless of sexual orientation, having undergone a tubal ligation, or remaining celibate by choice) who meets the following criteria: Has not undergone a hysterectomy or bilateral oophorectomy, or has not been naturally postmenopausal for at least 12 consecutive months (i.e., has had menses at any time in the preceding 12 consecutive months). Should a woman become pregnant or suspect she is pregnant while participating in this study, she should inform her treating physician immediately. Exclusion Criteria: Inability to receive further immune checkpoint inhibitor therapy Anticipated survival of fewer than 12 weeks Daily steroid requirement of > 10 mg prednisone or prednisone-equivalent. Steroid replacement therapy for adrenal insufficiency is permitted. Uncontrolled intercurrent illness including, but not limited to, ongoing or active infection, symptomatic congestive heart failure, unstable angina pectoris, cardiac arrhythmia, or psychiatric illness/social situations that, in the opinion of the investigator, would limit compliance with study requirements. Subjects must not be pregnant or nursing due to the potential for congenital abnormalities and the potential of this regimen to harm nursing infants.

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: SAbR 6 measurable lesions<br>PD-L1 assessment on biopsy of metastatic site (biopsy will be performed if no prior metastasis sample available) | Radiation: Stereotactic Ablative Radiation<br>* A stereotactic relocalization system that relies upon stereoscopic radiographs, implanted fiducials, or near real-time CT based verification will be used.Investigators will have the discretion to choose from biologically equivalent dose levels using 1, 3 or 5 fractions. All active lesions need to be addressed by local therapy<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Progression free survival (PFS) at 6 months | Progression free survival (PFS) at 6 months in the patients for whom SAbR is added to the ICI after progression on ICI. PFS will be defined as the combination of progressive disease from SAbR start date and death from any cause. | 6 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The disease control rate | The disease control rate in patients for whom SAbR is added to ICI after progression on ICI. DCR will be assessed per RECIST 1.1 criteria and defined as the combination of: Complete Response (CR), Partial Response (PR), or Stable Disease (SD). | 6 months | 
| The time to next-line systemic therapy | The time to initiation of next-line systemic therapy following the addition of SAbR to ICI after progression on ICI. | 6 months | 
| Overall survival of patients | The overall survival of patients since progression on ICI or at the study registration. Overall survival (OS) will be defined using the interval between enrollment and death from any cause. | 6 months |