Concurrent administration of BCMA and GPRC5D chimeric antigen receptor (CAR) T cells in advanced multiple myeloma

S Sham Mailankody (Cellular Therapy Service, Department of Medicine, Memorial Sloan Kettering Cancer Center, New York) S Sneha Mitra (Computational and Systems Biology Program, Memorial Sloan Kettering Cancer Center, New York) K Kevin Herrera B Bachisio Ziccheddu (Memorial Sloan Kettering Cancer Center, United States) B Briana Cadzin (Memorial Sloan Kettering Cancer Center, New York, New York, United States) O Ozgur Can Eren (Hematopathology Service, Department of Pathology and Laboratory Medicine, Memorial Sloan Kettering Cancer Center, New York) T Tasmin Farzana (Memorial Sloan Kettering Cancer Center, New York, New York, United States) T Tahmin Ullah (Memorial Sloan Kettering Cancer Center, New York, New York, United States) J Jonathan Landa (Memorial Sloan Kettering Cancer Center, New York, New York, United States) A Andriy Derkach J Jagrutiben Chaudhari (Memorial Sloan Kettering Cancer Center, New York, New York, United States) D Devin McAvoy (Sloan Kettering Institute, New York, New York, United States) K Kinga Hosszu (Memorial Sloan Kettering Cancer Center, New York, New York, United States) G Gunjan L. Shah (Cellular Therapy Service, Department of Medicine, Memorial Sloan Kettering Cancer Center, New York) H Heather J. Landau (Memorial Sloan-Kettering Cancer Center, New York, New York, United States) F Francesco Maura (Memorial Sloan Kettering Cancer Center, New York) A Ahmet Dogan (Hematopathology Service, Department of Pathology and Laboratory Medicine, Memorial Sloan Kettering Cancer Center, New York) S Sergio A. Giralt (Cellular Therapy Service, Department of Medicine, Memorial Sloan Kettering Cancer Center, New York) X Xiuyan Wang M Michel Sadelain E Eric L Smith (Dana-Farber Cancer Institute, Boston, Massachusetts, United States) R Renier J. Brentjens (Roswell Park Comprehensive Cancer Center, Buffalo, New York, United States) C Christina S Leslie (Memorial Sloan Kettering Cancer Center, New York, New York, United States) S Saad Z. Usmani (Memorial Sloan Kettering Cancer Center, New York) K Karlo Perica

Abstract

BCMA and GPRC5D-directed therapies have shown high efficacy in the treatment of relapsed or refractory myeloma with multiple new immune therapies now approved. Preclinical studies have shown that expression of BCMA and GPRC5D are heterogenous in malignant plasma cells. We conducted a phase I dose escalation trial of the BCMA CAR T cell therapy MCARH125 alone or in combination with the GPRC5D CAR T cell therapy MCARH109 in patients with heavily pre-treated relapsed or refractory multiple myeloma. Patients were treated across three dose levels and the primary objective of establishing safety of the concurrent infusion. The trial is registered in ClinTrials.gov, NCT05431608 and has now completed accrual. We treated 15 patients across 3 dose levels; this included 6 patients who received MCARH125 alone and 9 patients treated with concurrent infusion of MCARH125 and MCARH109. 1 patient each with MCARH 125 alone and the co-infusion of MCARH125 and MCARH109 developed immune effector cell associated hemophagocytic syndrome (IEC-HS). There were no instances of grade 3 or higher cytokine release syndrome (CRS) or immune effector cell associated neurologic syndrome (ICANS). The overall response for co-infusion was 78% with a median PFS of 18.2 months. Correlative analysis suggests that antigen loss maybe an important mechanism of resistance even with dual-antigen targeting and we show for the first time that expansion of one CAR population can limit expansion of the second population, as dual-CAR treated patients had significantly less BCMA-CAR expansion than BCMA-CAR alone treated patients, despite equivalent BCMA CAR T cell doses at infusion.

Article Details

Journal Blood
Volume / Issue Vol. 1, Issue 1
Published July 07, 2026
ISSN 0006-4971
Publisher Elsevier BV

Journal Info

Blood

Elsevier BV

ISSN: 0006-4971 Health Sciences

Authors (25)

S

Sham Mailankody

Cellular Therapy Service, Department of Medicine, Memorial Sloan Kettering Cancer Center, New York

S

Sneha Mitra

Computational and Systems Biology Program, Memorial Sloan Kettering Cancer Center, New York

K

Kevin Herrera

B

Bachisio Ziccheddu

Memorial Sloan Kettering Cancer Center, United States

B

Briana Cadzin

Memorial Sloan Kettering Cancer Center, New York, New York, United States

O

Ozgur Can Eren

Hematopathology Service, Department of Pathology and Laboratory Medicine, Memorial Sloan Kettering Cancer Center, New York

T

Tasmin Farzana

Memorial Sloan Kettering Cancer Center, New York, New York, United States

T

Tahmin Ullah

Memorial Sloan Kettering Cancer Center, New York, New York, United States

J

Jonathan Landa

Memorial Sloan Kettering Cancer Center, New York, New York, United States

A

Andriy Derkach

J

Jagrutiben Chaudhari

Memorial Sloan Kettering Cancer Center, New York, New York, United States

D

Devin McAvoy

Sloan Kettering Institute, New York, New York, United States

K

Kinga Hosszu

Memorial Sloan Kettering Cancer Center, New York, New York, United States

G

Gunjan L. Shah

Cellular Therapy Service, Department of Medicine, Memorial Sloan Kettering Cancer Center, New York

H

Heather J. Landau

Memorial Sloan-Kettering Cancer Center, New York, New York, United States

F

Francesco Maura

Memorial Sloan Kettering Cancer Center, New York

A

Ahmet Dogan

Hematopathology Service, Department of Pathology and Laboratory Medicine, Memorial Sloan Kettering Cancer Center, New York

S

Sergio A. Giralt

Cellular Therapy Service, Department of Medicine, Memorial Sloan Kettering Cancer Center, New York

X

Xiuyan Wang

M

Michel Sadelain

E

Eric L Smith

Dana-Farber Cancer Institute, Boston, Massachusetts, United States

R

Renier J. Brentjens

Roswell Park Comprehensive Cancer Center, Buffalo, New York, United States

C

Christina S Leslie

Memorial Sloan Kettering Cancer Center, New York, New York, United States

S

Saad Z. Usmani

Memorial Sloan Kettering Cancer Center, New York

K

Karlo Perica