Anti-IL6 antibody tocilizumab improved the ADC's cytotoxic activity in CD37+ cells...Adding idelalisib or venetoclax overcame resistance in the resistant derivative and improved the cytotoxic activity in the parental cells. In conclusion, targeting B-cell lymphoma with the naratuximab emtansine showed vigorous anti-tumor activity as a single agent, which was also observed in models bearing genetic lesions associated with inferior outcomes, such as MYC translocations and TP53 inactivation or R-CHOP resistance. Resistant DLBCL models identified active combinations of naratuximab emtansine with drugs targeting IL6, PI3Kδ, and BCL2.

Our work revealed that the clinically relevant anti-CD37 antibody drug conjugate (ADC) Debio 1562 (αCD37-DM1) is highly cytotoxic to AML blasts, but not normal hematopoietic stem cells. We found that αCD37-DM1 improved clinical outcomes and overall survival in multiple in vivo models of AML. Together, these data demonstrate that targeting CD37 with an ADC such as αCD37-DM1 is a feasible and promising therapeutic option for the treatment of AML.

Rituximab (RTX) plus chemotherapy (R-CHOP) applied as a first-line therapy for lymphoma leads to a relapse in approximately 40% of the patients...Importantly, even a major downregulation in CD37 levels does not hamper the efficacy of CD37-directed chimeric antigen receptor (CAR) T cells. In summary, we present here a novel mechanism of CD37 regulation with further implications for the use of anti-CD37 immunotherapies.

For those patients, CAR-T cells offers an attractive therapeutic option, as illustrated by the recent clinical trial combining CD19 CAR-T cells with ibrutinib... Targeting CD37 via CAR-T cells is a promising therapeutic option for CLL patients and an attractive alternative to CD19-directed CAR-based therapies. Further in vivo studies are warranted.

DL analysis of the co-expression and spatial arrangement of CD37 and CD20 positive cells in pre-treatment biopsies of DLBCL patients could potentially be used as a predictive biomarker for a response to a combination treatment of naratuximab emtansine and rituximab in DLBCL, and may improve patient stratification for further clinical trials.

DL analysis of the co-expression and spatial arrangement of CD37 and CD20 in pre-treatment biopsies of DLBCL patients could potentially be used as a predictive biomarker for a response to a combination treatment of anti-CD37 and anti-CD20 drugs in DLBCL, and may improve patient stratification for further clinical trials.

Moreover, upon cell surface binding, CD20 and CD37 antibodies were shown to form mixed hexameric antibody complexes consisting of both antibodies each bound to their own cognate target, so-called hetero-hexamers. These findings give novel insights into the mechanisms of synergy in antibody-mediated complement-dependent cytotoxicity and provide a rationale to explore Fc-engineering and antibody hetero-hexamerization as a tool to enhance the cooperativity and therapeutic efficacy of antibody combinations.