JULY 26, 2021, NEW YORK – A one-two punch envisioned as a way to improve CAR-T cell therapy for some blood cancers may be more challenging to implement than previously expected, according to a study led by Ludwig Stanford investigator Crystal Mackall and her Stanford colleague David Miklos and published online July 26 in Nature Medicine. Although CAR-T therapy directed against the CD19 molecule found on blood cancer cells is often initially successful, more than half of patients eventually relapse. Mackall, Miklos and colleagues studied whether simultaneously targeting two molecules, CD19 and CD22, would overcome resistance. But they found it was difficult to engineer CAR-T cells that were equally potent against each target. The researchers showed a correlation between the density of the target molecules on the cell surface and the likelihood that a patient will respond well to CAR-T therapy. They also show that patients with more than about 3,000 CD19 molecules per cell are more likely to respond well to CAR-T cell treatment, while those with fewer were more likely to relapse.
The Stanford Medicine release on this work can be found here.