Be Biopharma Announces Publication of Manuscript in the Molecular Therapy Journal Demonstrating In Vivo Engraftment and Tracking of Ex-vivo-Generated Plasma Cells in Non-Human Primates

Publication Demonstrates Engraftment of 20% of Infused Cells without Preconditioning with Consistent Distribution Upon Redosing

Manuscript Published in the Molecular Therapy Journal

CAMBRIDGE, Mass.--(BUSINESS WIRE)--Be Biopharma, Inc. (“Be Bio”), a clinical-stage company pioneering the discovery and development of engineered B Cell Medicines (BCMs), today announced the publication in the journal Molecular Therapy of a manuscript highlighting first-of-its-kind preclinical research from a collaboration study showing homing and engraftment of ex-vivo-generated plasma cells in non-human primates (NHPs) with intact immune systems. The study highlights the ability of these plasma cells to engraft in NHPs without preconditioning, validating a crucial aspect of the BCM platform designed to develop innovative programs with best-in-class profiles. The study was funded and conducted through a collaborative research and development agreement with the National Heart, Lung, and Blood Institute (NHLBI), part of the National Institutes of Health.

The publication, entitled “In vivo tracking of ex vivo generated ⁸⁹Zr-oxine labeled plasma cells by PET in a non-human primate model”, summarizes a study designed to evaluate engraftment without preconditioning of ex vivo expanded NHP plasma cells. Plasma cells are terminally differentiated B cells which can live for decades and have the capacity to secrete extremely high levels of protein. In the study, B cells from two NHPs were collected, expanded 10-15 fold ex vivo, and differentiated into antibody-secreting plasma cells. Using radioactive labeling and PET/CT imaging to track the cells after infusion, researchers found that 20% of the cells engrafted into the plasma cell niche by 24 hours and high-resolution imaging of the bone marrow compartment showed cellular distribution comparable to human bone marrow. A second infusion in one of the subjects showed remarkably similar distribution patterns to the first infusion, suggesting the feasibility of predicable re-dosing.

“These findings demonstrate the incredible potential of engineered B cells as a therapeutic platform and validate engraftment without preconditioning, a key pillar of our platform," said Richard Morgan, Ph.D., Chief Scientific Officer, Be Biopharma. "Our successful tracking and monitoring of these cells in non-human primates marks a crucial step toward developing B cell medicines that could potentially treat genetic disorders, metabolic diseases, and cancer. The safety profile and ability to perform repeated infusions are particularly encouraging and support our continued development of this innovative approach."

A phase 1/2 clinical trial, the BeCoMe-9 trial, has been initiated for Be Bio’s lead program, BE-101, in people with Hemophilia B, and Be Bio expects to initiate clinical development for BE-102 for the treatment of hypophosphatasia during 2026.

To read the published article, please visit https://www.cell.com/molecular-therapy-family/molecular-therapy/fulltext/S1525-0016(24)00842-6

Disclaimer: The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health.

About Engineered B Cell Medicines – A New Class of Cellular Medicines
The B cell is a powerful cell that produces thousands of proteins per cell per second at constant levels, and over decades. Precision genome editing can now be used to engineer B Cells that produce therapeutic proteins of interest, driving a new class of cellular medicines – Engineered B Cell Medicines (BCMs) – with the potential to be durable, allogeneic, redosable, and administered without pre-conditioning. The promise of BCMs could transform therapeutic biologics with broad application — across protein classes, patient populations and therapeutic areas.

About Be Biopharma
Be Biopharma (“Be Bio”) is pioneering Engineered B Cell Medicines (BCMs) to dramatically improve the lives of patients who are living with Hemophilia B and other genetic diseases, cancer, and other serious conditions. With eyes locked on the patient, our team of purpose-driven scientists, technologists, manufacturing experts and business builders collaborate to create a bold new class of cell therapies. Be Bio was founded in October 2020, and is backed by ARCH Venture Partners, Atlas Venture, RA Capital Management, Nextech, Alta Partners, Longwood Fund, Bristol Myers Squibb, Takeda Ventures, Seattle Children’s Research Institute and others to re-imagine medicine based on the power of Engineered B cells. For more information, please visit us at Be.Bio and our LinkedIn page.