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BioTheryX Presented Trial in Progress at ASH: A Phase I Trial of BTX-A51 in Patients with AML or High-Risk MDS

Current TAP Partner


Chappaqua, N.Y., December 7, 2020 - BioTheryX, Inc., a clinical stage biotechnology company creating new classes of compounds based on multi-kinase inhibition and targeted protein degradation, announced the initiation of patient dosing in its first clinical program back in January 2020. The Phase 1 study of BTX-A51, a small molecule, oral multi-kinase inhibitor will evaluate the safety, pharmacokinetics and tolerability of BTX-A51 in patients with relapsed/refractory AML, as well as high risk myelodysplastic syndrome patients. BTX-A51 appears to block a specific leukemic stem cell target (CK1-alpha) as well as super enhancer targets (CDK7/CDK9) preventing transcription of key oncogenic genes. BTX-A51 has demonstrated remarkable preclinical animal efficacy implying the eradication of AML stem cells and the potential for use in multiple malignancies.

Trial in Progress Summary:

This is an open-label, multi-center, first-in-human Phase 1 study evaluating the safety of BTX-A51 in patients with R/R AML or high-risk MDS. The trial will be performed in two phases, a dose escalation (phase 1a) and dose expansion (phase 1b). Phase 1a utilizes a hybrid accelerated titration with single patient cohorts to start for rapidly assessing up to 8 potential dosing cohorts. Up to a maximum of 35 patients will be enrolled in the dose escalation phase of the study at Memorial Sloan Kettering Cancer Center, MD Anderson Cancer Center, and City of Hope Cancer Center. Following determination of the MTD, 15 patients will be enrolled in the dose expansion phase for further evaluation of dose-limiting toxicities (DLTs) and for preliminary evidence of efficacy. 

  • The primary objective for the Phase 1 study is to determine the MTD and recommended Phase 2 dose (RP2D) of BTX-A51.
  • Secondary objectives include evaluating overall response (complete remission, complete remission with incomplete blood count recovery, and partial remission), survival (overall survival and event-free survival) and pharmacokinetics.
  • Correlative objectives include determining the changes in super-enhancers (SE) and SE-driven expression of antiapoptotic genes by chromatin immunoprecipitation and RNA-sequencing.
  • Recruitment is ongoing and this trial is registered on NCT04243785