The manufacturing process of a new type of chimeric antigen receptor (CAR) T- cell therapy is intrinsic to the product quality. That’s according to the CSO of a company who has seen promising early-stage results from a Phase I trial of bispecific CAR-T.

“We believe our manufacturing process is important to the outcomes being observed in patients,” explains Jim Johnston, PhD, CSO/COO of ImmPACT-Bio, which recently reported signs of long-term remission in a small study of patients with refractory non-Hodgkin’s B-cell lymphoma.

The company announced that six out of seven patients had ongoing complete remission after a median follow-up of nine months.

According to Johnston, a key part of ImmPACT’s manufacturing process involves enriching the patients’ T-cells that are more “stem-cell like” and thus less likely to become exhausted.

This is especially significant, he explains, because the patients have often been through multiple rounds of chemotherapy, which have left their T-cells in poor shape.

“It’s really important that we’re careful in the manufacturing process and that, as much as possible, the T cells are functional,” he says. “There are a number of reports that [poor functionality of] T cells in the product correlates with less optimal patient outcome. So, the manufacturing process is important.”

The company is working on a bispecific CAR-T, which recognises two antigens—CD19 and CD20—which are both expressed on the surface of B-cell lymphoma cells.

Most current CAR-T therapies target a single antigen, such as CD19.

“Approximately 50% of patients who are treated with CD19 CAR-T therapy don’t have long-term remission, sometimes as result of antigen loss and this technology is also attempting to address this, by improving the percentage of patients who achieve long-term complete remission by targeting more than one antigen,” continues Johnston, who is the former CSO of Kalthera, a spinout company from the University of California Los Angeles (UCLA) that he founded along with Yvonne Chen, PhD.

Kalthera recently announced their merger with ImmPACT with the aim of progressing their bispecific CAR-T therapy towards commercialization.

“We’re building a company that can deliver a Phase II clinical study,” explains Johnston. “The merged company is bringing a world-class team together and investing in a manufacturing facility to get that done.”