Edgewood Oncology Announces Positive Efficacy Data From Investigator-Sponsored Study of BTX-A51 in Preclinical Models of Liposarcoma

Edgewood Oncology, a clinical-stage biotechnology company focused on delivering BTX-A51 to patients with hematologic malignancies and genetically-defined solid tumors, today announced the publication of new preclinical data from a study of BTX-A51 in human liposarcoma (LPS) conducted by Dana-Farber Cancer Institute and Hebrew University-Hadassah Medical School to be presented at the AACR Annual Meeting 2024 in San Diego. BTX-A51 is a first-in-class, small molecule, multi-selective kinase inhibitor of casein kinase 1 alpha (CK1?) as well as the transcriptional regulators cyclin-dependent kinases 7 and 9 (CDK7 and CDK9) that synergistically co-targets master regulators of cancer to promote programmed cell death, or apoptosis.

The presentation (Abstract 604), "Targeting casein kinase 1 alpha (CK1alpha) and transcriptional CDKs (CDK7/9) in human liposarcomas," highlighted findings for BTX-A51 in preclinical human models of LPS. The data demonstrate that BTX-A51 has preclinical efficacy in treating patient-derived LPS in cell lines and human xenograft models and provides insight into the synergy gained by inhibiting both CK1? and CDK9.

"Dedifferentiated liposarcomas (DDLPS) are rare tumors derived from precursors of fat cells which can occur anywhere in the body. Patients with metastatic DDLPS face a life-threatening disease in need of more effective therapeutic options, which we hope to develop by taking advantage of vulnerabilities in LPS that have been uncovered by recent research on the abnormal DNA and other molecular characteristics of LPS," said George Demetri, M.D., Professor of Medicine and director of the Sarcoma Center at Dana-Farber. "Based on these data, we believe that it is justified to move BTX-A51 into a clinical trial for patients with LPS, which we will plan to open soon for enrollment."

Liposarcomas are universally characterized by amplification of the mouse double minute 2 homolog (MDM2) gene, which leads to destruction of the normal (non-mutated, also known as "wild type") p53. The data demonstrate that BTX-A51 significantly reduces the abnormal overexpression of MDM2 in multiple patient-derived LPS cell lines, leading to upregulation of p53 expression and ultimately apoptosis. Finally, BTX-A51 was demonstrated to be well-tolerated and effective in an LPS patient-derived xenograft model.

"We're pleased that investigators at Dana-Farber have taken an interest in BTX-A51, which is currently being evaluated in a Phase 2 combination study with azacitidine in patients with relapsed or refractory (R/R) AML," said David N. Cook, Ph.D., chief executive officer of Edgewood Oncology. "These data also suggest the potential for BTX-A51 in cancers with MDM2 amplifications, a group of genetically defined tumors that span multiple tissue types suggesting broader potential."

Additional Details about the Study

Using three different CDK9-selective inhibitors in human LPS cell lines, the authors showed that CDK9 inhibition suppressed cell growth and induced apoptosis by decreasing MDM2 levels while inducing expression of p53. It was also demonstrated that the potency of CDK9 inhibitors is significantly enhanced upon CK1? depletion. These data led to the investigation of BTX-A51, which targets CK1? and CDK9 as well as CDK7, in LPS cells and has previously been shown to inhibit these kinases with nanomolar efficacy in AML models. BTX-A51 potently reduced expression of MDM2 with marked induction of p53, resulting in apoptosis of LPS cells. BTX-A51 also reduces expression of MCL1 and primes LPS cell lines and primary LPS cells for BIM-induced apoptosis, as demonstrated by BH3 profiling. Importantly, preliminary in vivo data in an LPS patient-derived xenograft model reveal that BTX-A51 is well-tolerated under conditions that inhibit tumor growth.

About Edgewood Oncology

Edgewood Oncology is a clinical-stage biotechnology company that was founded to deliver on the promise of BTX-A51 for patients with hematologic malignancies and genetically-defined solid tumors. BTX-A51 is a novel small molecule, multi-kinase inhibitor that synergistically co-targets master regulators of cancer to activate programmed cell death, or apoptosis. BTX-A51 holds promise in acute myeloid leukemia and genetically-defined solid tumors, which are the focus of ongoing clinical programs. For more information, please visit www.edgewoodoncology.com, and follow us on LinkedIn.