Cellectis a clinical-stage biotechnology company using its pioneering gene-editing platform to develop life-saving cell and gene therapies, today presents clinical data on its Phase 1 AMELI-01 clinical trial (evaluating UCART123) that were unveiled in an oral presentation at the 64th American Society of Hematology (ASH) annual meeting, as well as preclinical data on multiplex engineering for superior generation of CAR T-cells, at the American Society of Gene and Cell Therapy (ASGCT) 2023 Annual Meeting.
Preliminary Clinical Data from the AMELI-01 Study Presented at ASH 2022
AMELI-01 is a Phase 1 open-label dose-escalation trial evaluating the safety, tolerability, expansion and preliminary activity of UCART123 given at escalating dose levels after lymphodepletion (LD) with either fludarabine and cyclophosphamide (FC) or FC with alemtuzumab (FCA) in patients with relapsed or refractory acute myeloid leukemia (r/r AML).
The oral presentation reviewed preliminary data from patients who received UCART123 at one of the following dose levels: dose level 1 (DL1) 2.5x105 cells/kg; dose level 2 (DL2) 6.25x105 cells/kg; intermediate dose level 2 (DL2i) 1.5x106 cells/kg; or dose level 3 (DL3) 3.30x106 cells/kg after lymphodepletion with FC ([n=8], DL1 – DL3) or FCA ([n=9], DL2 & DL2i).
Preliminary Safety Data
The FCA LD regimen resulted in robust lymphodepletion for greater than 28 days in all patients. Seven out of nine patients demonstrated UCART123 expansion, with maximum concentration (Cmax) ranging from 13,177 to 330,530 copies/μg DNA, an almost nine-fold increase compared with FC LD, and a significant increase in area under the curve (AUC) (0-28 days) (p=0.04; FC 10.2 vs. FCA 34.9).
Cytokine release syndrome (CRS) occurred in eight patients in the FC arm and nine patients in the FCA arm. In the FC arm, one patient experienced Grade 3 immune effector cell-associated neurotoxicity syndrome (ICANS) and two patients experienced Grade 4 protocol-defined dose limiting toxicities (DLTs) secondary to CRS. In the FCA arm, two patients experienced Grade 5 DLTs secondary to CRS.
Patient Enrollment in a 2-Dose Regimen Arm
Overall, these preliminary data support the continued administration of UCART123 after FCA lymphodepletion in patients with r/r AML. Based on observed UCART123 expansion patterns and cytokine profiles, pursuant to an amended protocol, a second dose of UCART123 is given after 10-14 days to allow for additional UCART123 expansion and clinical activity without the use of additional lymphodepletion. The UCART123 cell expansion from the second dose of UCART123, in the setting of reduced disease burden, is expected to be safe and allow for clearance of residual disease.
About Cellectis
Cellectis is a clinical-stage biotechnology company using its pioneering gene-editing platform to develop life-saving cell and gene therapies. Cellectis utilizes an allogeneic approach for CAR-T immunotherapies in oncology, pioneering the concept of off-the-shelf and ready-to-use gene-edited CAR T-cells to treat cancer patients, and a platform to make therapeutic gene editing in hemopoietic stem cells for various diseases. As a clinical-stage biopharmaceutical company with over 23 years of experience and expertise in gene editing, Cellectis is developing life-changing product candidates utilizing TALEN®, its gene editing technology, and PulseAgile, its pioneering electroporation system to harness the power of the immune system in order to treat diseases with unmet medical needs. Cellectis’ headquarters are in Paris, France, with locations in New York, New York and Raleigh, North Carolina. Cellectis is listed on the Nasdaq Global Market and on Euronext Growth .