NCT04601831

'Re-Priming' RT After Incomplete Response to CAR-T in R/R NHL

A Phase I/II Trial of 'Re-Priming' Radiation Therapy for Relapsed/Refractory Non-Hodgkin Lymphoma Patients in Incomplete Response After Chimeric Antigen Receptor T-cell (CAR-T) Therapy

• Status: Completed
• Phase: Phase 1 / Phase 2
• Study type: Interventional
• Enrollment: 14 (actual)
• Sponsor: University of Texas Southwestern Medical Center · Academic / Other
• Sex: All
• Age: 18 Years
• Healthy volunteers: Not accepted

Summary

This is a single-arm open-label phase I/II trial studying the safety and efficacy of focal 're-priming' radiation therapy (RT) to FDG-avid residual sites of disease in relapsed/refractory non-Hodgkin lymphoma (R/R NHL) patients with incomplete response (IR) to CAR T-cell therapy (CAR-T) by day 30 post-CAR-T PET/CT. We hypothesize that focal 're-priming' RT will be safe (phase I) and improve conversion to metabolic complete response (CR) by day 90 post-CAR-T PET/CT from 29% (historical control) to 58% (phase II).

Detailed description

Early clinical trials of CAR-T in R/R NHL suggest that only \~40% of patients achieve CR by day 30 PET/CT evaluation. Of those who do not, the large majority (\~70%) ultimately fail, while \~30% convert to CR after a median time of 64 days (range, 49-424). This group of patients, who have incomplete response on day 30 PET/CT after CAR-T and thus are most likely to fail CAR-T alone, may be the ideal target for early therapeutic intervention to 're-prime' CAR-T and convert them from IR to CR. Preclinical and early clinical studies suggest potential immune augmentation when combining RT with CAR-T. Therefore, we propose a phase I/II clinical trial investigating the impact of RT to poor responding sites of disease after CD19-directed CAR-T in R/R NHL patients who are likely to fail CAR-T alone. We hypothesize that focal RT to residual FDG-avid sites of disease on day 30 PET/CT will improve the number of patients who convert to CR by day 90 PET/CT both through local cytotoxic effects as well as local and systemic synergistic effects through 're-priming' of CAR T-cells.

Conditions

• Non-Hodgkin Lymphoma

Interventions

Type	Name	Description
RADIATION	Focal radiation therapy (RT)	Radiation therapy for phase II: "Definitive" 40-50 Gy EQD2 (i.e. 30 Gy in 5 fractions) Hypofractionated regimen (i.e. 5 fractions in 1-2 weeks) recommended, but other fractionation schemes (10-20 fractions in 2-4 weeks) allowed.

Timeline

• Start date: 2020-12-23
• Primary completion: 2024-08-06
• Completion: 2025-05-27
• First posted: 2020-10-26
• Last updated: 2025-10-16

Locations

1 site across 1 country: United States