A phase 2 trial of defibrotide for the prevention of chimeric antigen receptor T-cell-associated neurotoxicity syndrome.

Abstract

Chimeric antigen receptor T-cell (CAR-T) therapy represents a major advance in cancer immunotherapy; however, it can be associated with life-threatening neurotoxicity linked to blood-brain barrier disruption and endothelial activation. Defibrotide was shown to reduce endothelial cell activation in vitro and is approved in the United States for treatment of veno-occlusive disease/sinusoidal obstruction syndrome (VOD/SOS) in patients with renal or pulmonary dysfunction after hematopoietic cell transplantation (HCT), and in the European Union for severe VOD/SOS after HCT in patients aged >1 month. Defibrotide may stabilize the endothelium during CAR-T therapy and reduce the rate of CAR-T-associated neurotoxicity. This phase 2 study evaluated the safety and efficacy of defibrotide for prevention of CAR-T-associated neurotoxicity in patients with relapsed/refractory large B-cell lymphoma receiving axicabtagene ciloleucel. Part 1 established the recommended phase 2 dose (RP2D; 6.25 mg/kg); 20 patients (from parts 1 and 2) receiving the RP2D were evaluable for efficacy. Rate of CAR-T-associated neurotoxicity by day 30 (primary end point) was ∼50%, lower than reported in the ZUMA-1 trial (64%). Median event duration of grade ≥3 neurotoxicity was 7 days. No unexpected defibrotide-related safety findings and defibrotide-related treatment-emergent adverse events or deaths were reported. Results showed modest reduction in rate of CAR-T-associated neurotoxicity and high-grade neurotoxicity event duration relative to historical data; however, reduction was unlikely to meet the primary end point, so the study was terminated early. Nevertheless, results contribute valuable data for potential therapeutic insight on the management of CAR-T-associated neurotoxicity. This trial was registered at www.clinicaltrials.gov as #NCT03954106.

• Authors: Caron A Jacobson, Allison C Rosenthal, Jon Arnason, Shirali Agarwal, Peixin Zhang, Wendy Wu, Vian Amber, Jean A Yared
• Journal: Blood advances (Blood Adv) Vol. 7 Issue 21 Pg. 6790-6799 (Nov 14 2023) ISSN: 2473-9537 [Electronic] United States
• PMID: 37399456 (Publication Type: Clinical Trial, Phase II, Journal Article)
• Copyright: © 2023 by The American Society of Hematology. Licensed under Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0), permitting only noncommercial, nonderivative use with attribution. All other rights reserved.

Chemical References

• Receptors, Chimeric Antigen
• defibrotide
• cell-associated neurotoxicity
• Polydeoxyribonucleotides

Topics

• Humans
• United States
• Receptors, Chimeric Antigen (therapeutic use)
• Polydeoxyribonucleotides (therapeutic use)
• Hepatic Veno-Occlusive Disease (drug therapy)
• T-Lymphocytes