Off-the-shelf cell therapy
A defining characteristic of WU-CART-007 is its status as a "universal" or "allogeneic" CAR-T cell therapy. Most CAR-T therapies currently approved by the FDA are autologous, meaning they are manufactured using a patient’s own immune cells. This process requires collecting the patient’s cells, shipping them to a specialized manufacturing facility to be genetically engineered, and then shipping them back for infusion. This cycle can take anywhere from three to six weeks—a timeframe that many patients with aggressive, fast-moving leukemias simply do not have.
In contrast, the universal CAR-T cells evaluated in this trial are created using CRISPR gene editing technology and are derived from the cells of healthy donors. This allows the therapy to be manufactured in large batches, frozen, and stored for immediate use. This "off-the-shelf" availability significantly reduces the waiting period for patients, allowing them to begin treatment almost immediately after they are deemed eligible.
The use of CRISPR technology is central to making this universal approach work. When using donor cells, there is a high risk of graft-versus-host disease, where the donor’s T cells perceive the patient’s healthy tissues as foreign and attack them. To prevent this, the researchers used CRISPR to delete the T cell receptor from the donor cells.
Furthermore, the researchers had to solve a biological puzzle unique to T cell cancers: "fratricide." In standard CAR-T therapies for B cell cancers, the engineered T cells target a protein found on B cells. However, in this trial, both the treatment (T cells) and the target (cancerous T cells) share similar markers. Without further modification, the therapeutic CAR-T cells would identify each other as the enemy and destroy one another before they could reach the cancer. By using CRISPR to remove a specific antigen from the therapeutic cells, the researchers prevented them from attacking each other, ensuring they remained viable long enough to eliminate the cancer.
After these complex genetic modifications, the cells are further engineered to target a protein called CD7, which is prominently displayed on the surface of cancerous T cells. Once infused, these "predator" cells seek out and destroy any cell expressing CD7.
The success of this phase 1/2 trial has already paved the way for the next stage of clinical development. DiPersio confirmed that a larger, international clinical trial is currently underway to further validate these findings. While the completion of this larger trial is a prerequisite for regulatory approval, the research team is optimistic that this universal CAR-T cell therapy could eventually become a standard, approved treatment for patients facing the most deadly forms of T cell cancer.
