Cellectis Presents Preclinical Data on TALEN®-edited MUC1 CAR T-cells to Enhance Efficacy in Targeting Triple Negative Breast Cancer at the American Association for Cancer Research (AACR) Annual Meeting

April 17, 2023 – New York (NY) – 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 released preclinical data on TALEN^®-edited MUC1 CAR T-cells at the American Association for Cancer Research (AACR) Annual Meeting 2023. The data showed the capability of armored allogeneic MUC1 CAR T-cells to excel in the immune suppressive tumor micro-environment suggesting that they could be an effective option in treating relapsed and refractory triple negative breast cancer (TNBC) patients with limited therapeutic options.

Tumor-associated MUC1 antigen is overexpressed in a large number of TNBC patients offering an effective discriminatory target for CAR T-cell therapy.

Cellectis’ MUC1 CAR T-cells are allogeneic and target Mucin 1 for TNBC and a variety of epithelial cancers. As other solid tumor targets can be plagued by safety concerns due to off-tumor expression, MUC1 is of high interest as its expression in normal epithelium is restricted to apical membranes. Additionally, MUC1 heavy glycosylation in normal tissue contrasts with Cellectis’ MUC1 CAR that is designed to recognize hypoglycosylated MUC1 present in cancer cells. Cellectis’ MUC1 CAR T-cells incorporate up to four TALEN^®-mediated knockouts and two knock-ins.

“We are very excited to share these encouraging preclinical data at AACR that dissect how different attributes (knock-out or knock-in) contribute to the efficacy of our CAR T-cell product candidate” said Laurent Poirot, Ph.D., Senior Vice President Immunology at Cellectis. “We are convinced that allogeneic MUC1 CART-cells can be an effective option in the treatment of relapsed and refractory triple negative breast cancer.”

The poster presentation at AACR highlights the following preclinical data:

• Intratumoral delivery of antigen-specific CAR T-cells resulted in effective control of tumor growth.
• Results demonstrate superior activity of armored MUC1-CAR T-cells not only in tumor clearance but also in the recovery of normal glands.
• Thus, innovative strategies can be used to allow CAR T-cell efficiency in the hostile tumor microenvironment while preserving safety.

 

Title: Deciphering the benefits of variable delivery routes and molecular armoring to enhance efficacy of MUC1-CAR T-cells in targeting triple-negative breast cancer

Session Title: Adoptive Cell Therapy 1

Presenter: Piril, Erler, Ph.D., Scientist II, Immuno-Oncology, Cellectis

Session Date and time: Sunday April 16, 2023, 1:30-5:00 PM ET
Location: Section 37
Poster Board Number: 14
Abstract Presentation Number: 899

Poster of the presentation is available on Cellectis’ website: https://www.cellectis.com/en/investors/scientific-presentations/