Thefirst-in-human, universal chimeric receptor antigen (CAR) T-cell (CAR-T)therapy GC027 was tolerable and resulted in antileukemic responses amongpatients with relapsed/refractory T-cell acute lymphoblastic leukemia (T-ALL),according to results from a phase 1 trial presented at the American Associationfor Cancer Research (AACR) Virtual Annual Meeting I 2020.1

Theuniversal CAR T cells target CD7, which, according to Xinxin Wang, PhD, ofGracell Biotechnologies Co, Ltd, in China, and lead author and presenter of thestudy, is a good target for T-ALL because it is expressed by more than 95% ofT-ALL patients.

GC027 isallogeneic, which may prevent the development of graft-versus-host disease. Theproduct is introduced using lentivirus for rapid elimination of T-ALL cells. Preclinicalstudies showed efficacy in a T-ALL xenograft model, and this prospective studyevaluated the safety and efficacy in humans.

Thesingle-arm, open-label study treated 5 adult patients with relapsed/refractoryCD7-positive T-ALL with a single infusion of 1 of 3 different dose levels ofG027: 0.6 x 107/kg, 3 x 107/kg, and 1.5 x 107/kg.Lymphodepletion therapy was administered prior to the G027 infusion. Theprimary endpoint was safety and the secondary endpoints included objectiveresponse rate (ORR) within 3 months after G027 infusion.

Patientswith extramedullary or central nervous system disease were excluded. Atbaseline, the median age was 24 (range, 19-38). Patients were heavilypretreated, with 5 median number of prior therapies (range, 1-9). Two patientshad high-risk disease and the median bone marrow tumor burden was a median of38.2% of blasts. None of the patients had undergone a prior allogeneic hematopoieticstem cell transplant.

Allpatients developed cytokine release syndrome (CRS), 4 of which were grade 3 and1 was grade 4. All cases were manageable and resolved with treatment andsupportive care. None of the patients developed neurotoxicity.

The completeremission (CR)/CR with incomplete hematologic recovery was 100%. By day 28, 4patients achieved a CR with negative for minimal residual disease (MRD) and 3of these patients remained MRD negative up to day 161. One patient achieved CRbut was MRD positive, and relapsed by day 29.

Peak CART-cell expansion in peripheral blood occurred between week 1 and 2.

As the first-in-human, universal CAR T-cell therapy for adult relapsed/refractory T-ALL, Dr Wang said, GC027 has demonstrated superior clinical efficacy and induced deep response in patients with acceptable safety profile. She added that trial enrollment is ongoing.

Read more of Cancer Therapy Advisors coverage of AACR 2020 meeting by visiting the conference page.

Reference

Wang X, Li S, Gao L, et al. Clinical safety and efficacy study of TruUCAR GC027: The first-in-human, universal CAR-T therapy for adult relapsed/refractory T-cell acute lymphoblastic leukemia (r/r T-ALL). Presented at: American Association for Cancer Research (AACR) Virtual Annual Meeting I; April 27-28, 2020. Abstract CT052.

Excerpt from:
First-in-Human Universal CAR-T Therapy Found Active in Relapsed/Refractory T-ALL - Cancer Therapy Advisor