Cellectis Announces Two Poster Presentations on Novel TALEN® Editing Process for Gene Correction and Gene Insertion in HSPCs at the ASGCT Annual Meeting

New York, NY – April 8, 2024 – Cellectis (the “Company”) (Euronext Growth: ALCLS - NASDAQ:  CLLS), a clinical-stage biotechnology company using its pioneering gene-editing platform to develop life-saving cell and gene therapies, today announced that preliminary data exploring novel TALEN^® editing process in hematopoietic stem and progenitor cells (HSPCs) will be presented at the American Society of Gene and Cell Therapy (ASGCT) 27^th Annual Meeting, to be held in Baltimore, Maryland, on May 7-11, 2024.

Poster presentations:

Title: Circularization of Non-Viral Single-Strand DNA Template for Gene Correction and Gene Insertion Improves Editing Outcomes in HSPCs

Presenter: Alex Boyne, Gene Editing Platform Manager at Cellectis

Session Date/Time: May 9, 2024 at 12PM ET
Session Title: Nonviral Therapeutic Gene Delivery and Synthetic/Molecular Conjugates
Presentation Room: Exhibit Hall
Final Abstract Number: 1235

Cellectis presents the development of a novel gene editing process, leveraging the TALEN^® technology and non-viral DNA template delivery, enabling highly efficient gene correction and gene insertion in hematopoietic stem and progenitor cells (HSPCs).

Title: Intron Editing of HSPC Enables Lineage-Specific Expression of Therapeutics

Presenter: Julien Valton, Ph.D., Vice President Gene Therapy at Cellectis

Session Date/Time: May 8, 2024 at 12PM ET
Session Title: Gene Targeting and Gene Correction New Technologies
Presentation Room: Exhibit Hall
Final Abstract Number: 721

Gene therapy using hematopoietic and progenitor stem cells (HSPC) has the potential to provide a lifelong supply of genetically encoded therapeutics. Gene editing strategies enabling supra-endogenous expression of therapeutics often rely on constitutive promoters resulting in transgene overexpression irrespective of cellular differentiation, which could be detrimental for HSPC function. Cellectis presents the development of a TALEN^® mediated promoter-less intron editing strategy that relies on the endogenous cellular RNA splicing machinery to induce lineage-specific transgene expression exclusively after HSPC differentiation.

Full abstracts and presentations will be available on Cellectis’ website following the event:

https://www.cellectis.com/en/investors/scientific-presentations/