Addressing the need for superior toxin delivery and safety for AML and MDS therapies, Marx et al. developed Debio 1562M, a next-generation ADC targeting CD37, which is broadly expressed on AML and MDS blasts. Debio 1562M (with a drug [DM1]-to-naratuximab ratio of 8, and a cathepsin-cleavable linker) was efficiently internalized and killed blast cells in blood and bone marrow. In multiple models, Debio 1562M outperformed standard-of-care treatments, and demonstrated broad and efficient anti-leukemic activity on all AML subtypes. Compared to 1st generation CD37 ADC, Debio 1562M had an improved toxicity profile in mice, and is in a phase 1 trial for r/r AML and high-risk MDS.
Contributed by Katherine Turner
ABSTRACT: The leukocyte antigen CD37 is broadly expressed on acute myeloid leukemia (AML) blasts and associated with poor prognosis. We demonstrate that myelodysplastic syndrome (MDS) cells also express CD37, and both AML and MDS cells have favorable internalization properties of this receptor. Debio 1562M is a next-generation antibody-drug conjugate (ADC) that targets CD37 and is optimized to deliver more toxins to tumor cells than the first-generation ADC Debio 1562, while maintaining a good safety profile. Preclinically, Debio 1562M showed robust anti-leukemic activity in AML and MDS primary samples and in AML xenograft models, irrespective of disease stage or genotype. Debio 1562M was able to target leukemic stem cells in vitro and significantly decrease tumor burden in blood and bone marrow, resulting in survival prolongation compared with standard-of-care treatments. These data demonstrate that CD37 is a relevant target for both indications and that Debio 1562M is a promising therapeutic candidate.
Author Info: (1) Debiopharm Research and Manufacturing SA, 1920 Martigny, Switzerland. (2) Debiopharm International SA, 1006 Lausanne, Switzerland. (3) Debiopharm International SA, 1006 Lausann
Author Info: (1) Debiopharm Research and Manufacturing SA, 1920 Martigny, Switzerland. (2) Debiopharm International SA, 1006 Lausanne, Switzerland. (3) Debiopharm International SA, 1006 Lausanne, Switzerland. (4) Debiopharm Research and Manufacturing SA, 1920 Martigny, Switzerland. (5) Debiopharm Research and Manufacturing SA, 1920 Martigny, Switzerland. (6) Comprehensive Cancer Center, The Ohio State University, Columbus, OH 43210, USA. (7) Comprehensive Cancer Center, The Ohio State University, Columbus, OH 43210, USA. (8) Debiopharm International SA, 1006 Lausanne, Switzerland. (9) Debiopharm International SA, 1006 Lausanne, Switzerland. (10) Debiopharm International SA, 1006 Lausanne, Switzerland. (11) Comprehensive Cancer Center, The Ohio State University, Columbus, OH 43210, USA. (12) Debiopharm International SA, 1006 Lausanne, Switzerland. Electronic address: lisa.ivanschitz@debiopharm.com.
