Biallelic antigen escape is a mechanism of resistance to anti-CD38 antibodies in multiple myeloma

B Benjamin Diamond (University of Miami) L Linda Baughn (2Division of Laboratory Genetics, Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, United States) M Mansour Poorebrahim (1University of Calgary, Arnie Charbonneau Cancer Institute, Calgary, Canada) A Alexandra M. Poos (4Heidelberg Myeloma Center, Department of Internal Medicine V, Medical Faculty, Heidelberg University Hospital, Heidelberg University, Heidelberg, Germany) H Holly Lee (University of Calgary) M Marcella Kaddoura (1Myeloma Division, Sylvester Comprehensive Cancer Center, University of Miami Health System, Miami, FL) J J. Erin Wiedmeier-Nutor (2Department of Medicine, Mayo Clinic, Phoenix, AZ) M Michael Durante (1Myeloma Division, Sylvester Comprehensive Cancer Center, University of Miami Health System, Miami, FL) G Gregory Otteson (1Mayo Clinic, Division of Hematopathology, Rochester, United States) D Dragan Jevremovic (1Mayo Clinic, Rochester, United States) H Hongwei Tang S Stefan Fröhling M Marc A. Baertsch (4Heidelberg Myeloma Center, Department of Internal Medicine V, Medical Faculty, Heidelberg University Hospital, Heidelberg University, Heidelberg, Germany) M Marios Papadimitriou (1Myeloma Institute, Sylvester Comprehensive Cancer Center, University of Miami, Miami, United States) B Bachisio Ziccheddu (Memorial Sloan Kettering Cancer Center, United States) T Tomas Jelinek (Department of Hemato-oncology, University Hospital Ostrava, Ostrava, Czech Republic) C Cendrine Lemoine (12Department of eBiology, Large Molecule Research, Sanofi R&D, Vitry-sur-Seine, France) A Alexey Rak (13Department of Bio Structure and Biophysics, Integrated Drug Discovery, Sanofi R&D, Vitry-sur-Seine, France) D Damian J. Green O Ola Landgren P Paola Neri (1University of Calgary) L Leif Bergsagel E Esteban Braggio (2Department of Medicine, Mayo Clinic, Phoenix, AZ) S Shaji Kumar M Marc S. Raab R Rafael Fonseca (IDOMED Vista Carioca, RIO DE JANEIRO, Brazil) N Nizar Bahlis (2Arnie Charbonneau Cancer Institute, University of Calgary, Calgary, Canada) N Niels Weinhold F Francesco Maura (Memorial Sloan Kettering Cancer Center, New York)

Abstract

Abstract Monoclonal antibodies targeting CD38 are a therapeutic mainstay in multiple myeloma (MM). Although they have contributed to improved outcomes, most patients still experience disease relapse, and little is known about tumor-intrinsic mechanisms of resistance to these drugs. Antigen escape has been implicated as a mechanism of tumor-cell evasion in immunotherapy. Yet, it is unknown whether MM cells can develop permanent resistance to anti-CD38 antibodies by acquiring genomic events leading to biallelic disruption of the CD38 gene locus. Here, we analyzed whole-genome and whole-exome sequencing data from patients 701 newly diagnosed MM, 67 patients at relapse with naivety to anti-CD38 antibodies, and 50 patients collected at relapse after anti-CD38 antibodies. We report a loss of CD38 in 10 of 50 patients (20%) after CD38 therapy, 3 of whom exhibited a loss of both copies. Two of these cases showed convergent evolution in which distinct subclones independently acquired similar advantageous variants. Functional studies on missense mutations involved in biallelic CD38 events revealed that 2 variants, L153H and C275Y, decreased binding affinity and antibody-dependent cellular cytotoxicity of the commercial antibodies daratumumab and isatuximab. However, a third mutation, R140G, conferred selective resistance to daratumumab, while retaining sensitivity to isatuximab. Clinically, patients with MM are often rechallenged with CD38 antibodies after disease progression and these data suggest that next-generation sequencing may play a role in subsequent treatment selection for a subset of patients.

Article Details

Journal Blood
Volume / Issue Vol. 146, Issue 13
Published September 25, 2025
Pages 1575-1585
ISSN 0006-4971
Publisher Elsevier BV

Journal Info

Blood

Elsevier BV

ISSN: 0006-4971 Health Sciences

Authors (29)

B

Benjamin Diamond

University of Miami

L

Linda Baughn

2Division of Laboratory Genetics, Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, United States

M

Mansour Poorebrahim

1University of Calgary, Arnie Charbonneau Cancer Institute, Calgary, Canada

A

Alexandra M. Poos

4Heidelberg Myeloma Center, Department of Internal Medicine V, Medical Faculty, Heidelberg University Hospital, Heidelberg University, Heidelberg, Germany

H

Holly Lee

University of Calgary

M

Marcella Kaddoura

1Myeloma Division, Sylvester Comprehensive Cancer Center, University of Miami Health System, Miami, FL

J

J. Erin Wiedmeier-Nutor

2Department of Medicine, Mayo Clinic, Phoenix, AZ

M

Michael Durante

1Myeloma Division, Sylvester Comprehensive Cancer Center, University of Miami Health System, Miami, FL

G

Gregory Otteson

1Mayo Clinic, Division of Hematopathology, Rochester, United States

D

Dragan Jevremovic

1Mayo Clinic, Rochester, United States

H

Hongwei Tang

S

Stefan Fröhling

M

Marc A. Baertsch

4Heidelberg Myeloma Center, Department of Internal Medicine V, Medical Faculty, Heidelberg University Hospital, Heidelberg University, Heidelberg, Germany

M

Marios Papadimitriou

1Myeloma Institute, Sylvester Comprehensive Cancer Center, University of Miami, Miami, United States

B

Bachisio Ziccheddu

Memorial Sloan Kettering Cancer Center, United States

T

Tomas Jelinek

Department of Hemato-oncology, University Hospital Ostrava, Ostrava, Czech Republic

C

Cendrine Lemoine

12Department of eBiology, Large Molecule Research, Sanofi R&D, Vitry-sur-Seine, France

A

Alexey Rak

13Department of Bio Structure and Biophysics, Integrated Drug Discovery, Sanofi R&D, Vitry-sur-Seine, France

D

Damian J. Green

O

Ola Landgren

P

Paola Neri

1University of Calgary

L

Leif Bergsagel

E

Esteban Braggio

2Department of Medicine, Mayo Clinic, Phoenix, AZ

S

Shaji Kumar

M

Marc S. Raab

R

Rafael Fonseca

IDOMED Vista Carioca, RIO DE JANEIRO, Brazil

N

Nizar Bahlis

2Arnie Charbonneau Cancer Institute, University of Calgary, Calgary, Canada

N

Niels Weinhold

F

Francesco Maura

Memorial Sloan Kettering Cancer Center, New York