NATIONAL HARBOR, MD – An armored chimeric antigen receptor (CAR) T-cell therapy has demonstrated efficacy in vitro and in patients with relapsed or refractory non-Hodgkin lymphoma (NHL), according to findings presented at the annual meeting of the Society for Immunotherapy of Cancer.
ICTCAR014, a dominant negative PD-1 armored CAR T-cell therapy, proved more cytotoxic than traditional CAR T-cell therapy in vitro and produced responses in 12 of 13 NHL patients who received it.
, of Innovative Cellular Therapeutics, Shanghai, China, presented results with ICTCAR014 at the meeting.
Dr. Lu explained that ICTCAR014 consists of CD19-targeted CAR T cells genetically engineered to overexpress a PD-1 dominant negative protein with an altered intracellular signaling domain. The dominant negative protein can act as a “decoy receptor” to bind and block the PD-L1/2 inhibitory signal, thereby enhancing the efficacy of CAR T cells.
Innovative Cellular Therapeutics is developing ICTCAR014 because there is “some room to improve” with commercially available CAR T-cell products, Dr. Lu said. Specifically, tisagenlecleucel produced a 52% response rate in the JULIET trial (), and axicabtagene ciloleucel produced an 82% response rate in the ZUMA-1 trial ( ).
There is also evidence to suggest that PD-1 blockade can modulate and “refuel” CAR T cells in relapsed/refractory NHL patients who fail or relapse after traditional anti-CD19 CAR T-cell therapy (). This finding has prompted researchers to conduct trials of PD-1 inhibitors in combination with CAR T-cell therapies. But this combination approach may be expensive and cause more side effects than the armored CAR T-cell approach, Dr. Lu said.
In preclinical studies, Dr. Lu and colleagues found that ICTCAR014 was more effective than traditional anti-CD19 CAR T cells in killing Nalm6-PDL1 cells. In addition, the PD-1 dominant negative protein protected CAR T cells from exhaustion.
Dr. Lu also presented results in 13 NHL patients who have received ICTCAR014 in a phase 1 trial in China. Eleven patients had diffuse large B-cell lymphoma (DLBCL), and two had follicular lymphoma.
The objective response rate was 92.3% (12/13), which included five partial responses (38.5%) and seven complete responses (53.8%). Both follicular lymphoma patients and five DLBCL patients achieved a complete response. Five DLBCL patients achieved a partial response, and the remaining DLBCL patient did not respond.
Dr. Lu did not present safety data. However, he reported that there was no increased incidence of cytokine release syndrome or neurotoxicity in these patients, compared with patients receiving traditional CAR T-cell therapy.
Dr. Lu is employed by Innovative Cellular Therapeutics, which funded the research and is developing ICTCAR014.
SOURCE: Lu V et al. SITC 2019, .