Cellectis stated that its licensed partner, Allogene Therapeutics Inc. announced that the U.S. Food and Drug Administration (FDA) has lifted the hold on its clinical trials. The FDA had placed a clinical hold on all five of Allogene's clinical trials on October 7, 2021 following a report of a chromosomal abnormality detected in ALLO-501A CAR+ T-cells from a single patient enrolled in Allogene's ALPHA2 study. Allogene reported that the investigations concluded that the chromosomal abnormality was unrelated to TALEN® gene editing or Allogene's manufacturing process and had no clinical significance.

The abnormality was not detected in any manufactured AlloCAR T™ product or in any other patient treated with the same ALLO-501A lot. The abnormality occurred in the patient after the cell product was administered. It involved regions of the T cell receptor and immunoglobulin genes known to undergo rearrangement as part of the natural T cell or B cell maturation process.

Allogene also announced that following the lift of the clinical holds and pending final discussions with the FDA, Allogene intends to initiate a Phase 2 pivotal trial of ALLO-501A in relapsed/refractory large B-cell lymphoma mid-year 2022. Allogene's allogeneic CAR-T programs utilize Cellectis' technologies. ALLO-501 and ALLO-501A are anti-CD19 products being jointly developed under a collaboration agreement between Servier and Allogene based on an exclusive license granted by Cellectis to Servier.

Servier grants to Allogene exclusive rights to ALLO-501 and ALLO-501A in the U.S. while Servier retains exclusive rights for all other countries. Allogene has an exclusive license to Cellectis' technologies for ALLO-715, ALLO-605 (both directed at BCMA) and ALLO-316 (directed at CD70) and holds development and commercial rights for these investigational product candidates.