Cimeio Therapeutics : CD45 ADC and Shielded HSCs Represent a Potentially Universal Therapy for Blood Cancers

— Selective and complete eradication of leukemic cells with an ADC targeting the pan-blood marker CD45 —

— Engineered hematopoietic Stem Cells (HSCs) shielded from the CD45-targeting ADC maintain full functionality —

— Represents a novel, potentially universal approach to treating blood cancers —

BASEL, Switzerland & CAMBRIDGE, Mass.–(BUSINESS WIRE)–Cimeio Therapeutics today announced a publication in Nature showing that its CD45 antibody-drug conjugate (ADC) eradicated aggressive leukemic cells in vivo, while hematopoiesis was fully preserved and protected from the ADC via shielded hematopoietic stem cells (HSCs). The findings point to a novel and potentially universal approach to treating blood cancers.

CD45 is highly expressed on blood cancers but also on healthy blood cells. This profile until now has prevented effective targeting for therapeutic purposes. Now, a group led by Dr. Lukas Jeker, and researchers at Cimeio have shown that acute myeloid leukemia (AML) cells can be eliminated using Cimeio’s proprietary CD45-targeting ADC. By transplanting engineered HSCs that are shielded from the CD45-directed therapy, the CD45 ADC was safely and effectively administered against the blood cancers.

This work is foundational for the emerging field called epitope shielding, which enables the development of curative therapies for patients with hematologic diseases, severe autoimmune conditions and potentially infectious diseases such as HIV. The core patent for epitope shielding is exclusively licensed to Cimeio by University of Basel.

“All AML cells express CD45 but since all healthy blood cells also express it, killing cells that express CD45 results in severe toxicity,” said Dr. Jeker, who is the co-founder of Cimeio and Professor of Experimental Transplantation Immunology & Nephrology at the Basel University Hospital, Switzerland. “We solved the problem by providing epitope-shielded HSCs, which enable the ADC to selectively deplete cancer cells while sparing the healthy ones.”

“We believe that this therapy could change the treatment paradigm for patients with AML, which is a difficult-to-treat disease with a five-year survival rate of only 25%,” said Stefanie Urlinger, Ph.D., Chief Scientific Officer at Cimeio. “By protecting a patient’s heme system from toxicity, we are able to develop new targeted treatments previously not possible.”

Cimeio Therapeutics is developing epitope engineered cells and paired targeted therapies for CD45 and CD117, and epitope engineered cells for CD33, CD52, and several other heme targets.

About Cimeio Therapeutics

Cimeio is an immunotherapy company developing Shielded-Cell & Immunotherapy Pairs™ (SCIP), novel immunotherapies which have the potential to transform treatment of hematologic diseases. Cimeio develops immunotherapies, along with paired, modified variants of naturally occurring cell surface proteins in HSCs. These novel epitopes edited variants maintain their function but are resistant to depletion when targeted by a paired immunotherapy which has high affinity for the wild-type version of these proteins. These immunotherapies have significant therapeutic potential, which Cimeio is using to develop curative treatments for patients with hematologic malignancies, autoimmune disorders, and genetic diseases. Shielded Cell and Immunotherapy Pairs and SCIP are trademarks of Cimeio Therapeutics, Inc. For more information, please visit


Steve Edelson