ABL Bio said it would disclose pre-clinical data of ABL602, an acute myeloid leukemia (AML) treatment, at the European Society for Medical Oncology (ESMO 2022) meeting in early September.
The pre-clinical data has been selected as one of the key oral presentations in hemato-oncology at ESMO 2022 in Paris on Sept. 12.
The upcoming data release follows the company’s presentation of ABL602’s animal model results at the American Society of Hematology meeting in the U.S. in December (ASH 2021).
The oral presentation title will be, “An asymmetrical CLL1/CD3 bispecific antibody, ABL602, exhibits CLL-1 binding-dependent CD3 binding/activation and antitumor activity in AML’s mouse model and leukemia blasts from AML patients.”
ABL602 is an immunoglobulin G(IgG)-based bispecific antibody that targets CLL-1 (also known as C-type lectin-like molecule-1, CLEC12A) and CD3.
The company decided to develop ABL602 because CLL-1 is expressed limitedly in leukemia stem cells, despite its absence in normal hematopoietic stem cells.
ABL602 is an asymmetric bispecific antibody that binds to CLL01 and CD3 in “2+1” format.
According to the company, ABL602 demonstrated higher binding activity to CLL-1-expressing AML cell lines and greater tumor-killing effect than MCLA-117, a “1+1” format bispecific benchmark antibody developed but dropped by Merus.
In the poster presentation at ASH 2021 last year, ABL Bio unveiled ABL602 for the first time. At the time, the treatment candidate showed statistically significant antitumor activity in a dose-dependent manner.
“ABL602 induced potent cytotoxic activities on CLL1-expressing AML cell lines with concomitant T cell activation and cytokine/granzyme B release,” the research team said. “Despite the strong antitumor activity, ABL602 preserved CLL-1-negative cancer cell lines. This indicates that ABL602 induces CLL-1-dependent cytotoxicity.”
The research team noted that ABL602 promoted T-cell activity specifically against CLL1-expressing AML cells.
“It is a promising treatment strategy for AML patients by achieving the desired balance between antitumor activity and safety,” the research team added.
ABL602’s data presented at ASH 2021 was from the AML mouse model.
This time, the company will add data from AML patients’ leukemia blasts.
At ESMO 2022, only seven abstracts were selected for the mini oral session in hemato-oncology, and ABL602 is the only treatment candidate in the pre-clinical stage.
Attention is on how oncologists will evaluate ABL602 during the discussion after the presentation of the data.