On August 1, 2022, base editing company Beam Therapeutics announced that its IND application for BEAM-201 was suspended by the FDA. The FDA will provide more details on the decision within 30 days, and Beam promises to update as more details become available.
In June this year, the therapy submitted to the FDA for the treatment of relapsed or refractory T-ALL (acute T lymphoblastic leukemia) and other CD7-positive malignancies. This is also the first CAR-T that has edited 4 genes at the same time. therapy.
In October 2017, the FDA approved the launch of the first CAR-T cell therapy. Humans have entered the era of cell therapy. CAR-T cell therapy has achieved good clinical results in blood cancers.
At present, several CAR-T cell therapies that have been marketed use autologous T cells from cancer patients. The advantage of autologous cell therapy is that it can function in the patient for a long time without causing rejection, but this method There are also many limitations. Autologous cell therapy takes a long time, some acute leukemia patients do not have enough time to wait, and many severe patients do not have enough T cells themselves for engineering.
Therefore, CAR-Ts constructed from T cells derived from healthy donors can avoid the above problems and potentially develop “off-the-shelf” CAR-T products. But this requires additional modifications to CAR-T cells to prevent graft-versus-host disease (GvHD) and the body’s rejection of CAR-T cells.
At present, many studies and some clinical trials have used CRISPR-Cas9 gene editing technology to construct allogeneic “spot type” CAR-T cells. But one issue that requires special attention is that CRISPR-Cas9 relies on DNA double-strand breaks (DSBs) for gene editing, which can lead to many unintended consequences that affect the “spot type” produced in this way Availability, safety, and approval of CAR-T.
On May 16, 2022, Beam Therapeutics, a base editing company, cooperated with the Children’s Hospital of Philadelphia, USA, and published a research paper entitled: Cytosine Base Editing Enables Quadruple-Edited Allogeneic CAR-T Cells for T-ALL in Blood, a top journal of hematology. .
This study used cytosine base editing (CBE) to construct a quadruple base-edited CAR-T cell against the CD7 target, 7CAR8, designed for allogeneic CAR-T cells. The therapeutic effect of 7CAR8 on relapsed or refractory T-ALL (acute T lymphoblastic leukemia) and other CD7-positive malignancies has been confirmed in preclinical animal models.
It is reported that this is also the first CAR-T therapy that has edited 4 genes at the same time. At present, this therapy has been submitted for IND application, and human clinical trials will be carried out in the second half of this year.