Autolus Submits Obe-Cel BLA for Adult R/R B-ALL

Autolus Therapeutics has submitted its biologics license application (BLA) for obecabtagene autoleucel (obe-cel) chimeric antigen receptor (CAR) T-cell therapy for treating patients with relapsed/refractory (r/r) adult B-cell acute lymphoblastic leukemia (B-ALL).¹

“We are looking forward to continuing working with the FDA through the regulatory approval process,” commented Christian Itin, PhD, chief executive officer, Autolus, said in a statement.¹ “I would like to thank the treating physicians, patients, caregivers, and the dedicated team at Autolus for their support, trust and commitment for the program to reach this important milestone.”

Obe-cel (AUTO1) is a CD19-targeted autologous CAR T-cell therapy designed with a fast target binding off-rate to minimize excessive T-cell activation. Autolus stated that this design has demonstrated reduced toxicity and T-cell exhaustion in clinical trials, leading to improved persistence and durable remissions. The FDA has granted Orphan Drug and Regenerative Medicine Advanced Therapy (RMAT) designations to the therapy and the European Medicines Agency (EMA) has granted Orphan Medical Product and PRIority MEdicines (PRIME) designations to it for adults with r/r B-ALL.

The BLA submission is based on data from the pivotal Phase 2 FELIX trial (NCT04404660) of obe-cel in adults with r/r B-ALL. The trial had a Phase 1b component prior to proceeding to the single arm, Phase 2 clinical trial. FELIX’s primary endpoint is overall response rate, and the secondary endpoints include duration of response (DOR), minimal residual disease (MRD) negativity, complete response (CR) rate, and safety and tolerability. The trial has enrolled over 100 patients across 30 centers in the US and Europe.

WATCH NOW: Claire Roddie PhD, FRCPath, MBChB, MRCP, on Evaluating Obe-cel in Patients With R/R B-ALL

Autolus most recently presented data from FELIX at the American Society of Clinical Oncology (ASCO) 2023 Annual Meeting, held June 2-6, in Chicago, Illinois. The data were from 94 patients, 76% of which achieved either a CR (54.3%) or a CR with incomplete blood count recovery (21.3%). The ORR was 76% (95% CI, 66-84; 1-sided P < .0001) and 97% of patients who responded and had evaluable samples achieved MRD negativity at the 10-4 level when evaluated by flow cytometry. At a median follow-up of 9.5 months, 61% of patients who responded continued to remain in remission without receiving new anticancer therapies. The median DOR was 14.1 months (95% CI, 5.9, not estimable). There were 71 patients (75.5%) that experienced cases of cytokine release syndrome (CRS), with 3 cases (3.2%) grade 3 or higher; there were 24 patients (25.5%) that experienced cases of immune effector cell-associated neurotoxicity syndrome (ICANS), with 7 cases (7.4%) grade 3 or higher. The most common grade 3 or higher treatment-emergent adverse events experienced by patients in the trial was neutropenia (36.2%). One patient death deemed related to obe-cel occurred, which was attributed to hemophagocytic lymphohistiocytosis and neutropenic sepsis.²

Autolus plans to submit a Marketing Authorization Application for obe-cel in the same indication to the EMA in the first half of 2024. Obe-cel is also being evaluated in a trial in collaboration with University College London for patients with B-cell non-Hodgkin lymphoma.¹

REFERENCES

1. Autolus Therapeutics submits biologics license application to U.S. Food and Drug Administration for obecabtageneautoleucel (obe-cel) for patients with relapsed/refractory (r/r) adult B-cell acute lymphoblastic leukemia (ALL). November 27, 2023. https://autolus.gcs-web.com/news-releases/news-release-details/autolus-therapeutics-submits-biologics-license-application-us
2. Roddie C, Sandhu KS, Tholouli E, et al. Safety and efficacy of obecabtageneautoleucel (obe-cel, AUTO1), a fast-off rate CD19 CAR, in relapsed/refractory adult B-cell acute lymphoblastic leukemia (r/r B-ALL): Top line results of the pivotal FELIX study. Presented at: the American Society of Clinical Oncology (ASCO) 2023 Annual Meeting, held June 2-6, in Chicago, Illinois. Abstract #7000