SAN DIEGO, CA, USA and TORONTO, Canada I November 26, 2018 I Aptose Biosciences Inc. (NASDAQ: APTO, TSX: APS), a clinical-stage company developing highly differentiated therapeutics targeting the underlying mechanisms of cancer, today announced that dosing has commenced in the first patient in its Phase 1b clinical study of APTO-253 in patients with relapsed or refractory hematologic malignancies.  APTO-253 is the only known clinical-stage molecule that can directly inhibit expression of the MYC oncogene, shown to reprogram survival signaling pathways in cells and thereby transform cells and contribute to drug resistance in many malignancies, including acute myeloid leukemia (AML). 

“We are pleased to announce the successful re-initiation of patient dosing in our clinical trial with APTO-253, our first-in-class inhibitor of the MYC oncogene that has the potential to benefit a large patient population across various therapeutic areas, and we look forward to providing updates moving forward,” commented William G. Rice, Ph.D., Chairman, President and CEO.  “As the clinical protocol requires only one patient at each of the two lowest dose levels, we have and will continue to carefully select patients for those first two dose levels. Relapsed/refractory AML patients tend to be acutely sick, and we seek to complete those two lower dose levels with a favorable tolerability profile.  Indeed, we hope this thoughtful approach will allow expeditious escalation to higher dose levels and may provide greater benefit to the AML patients.”

About the APTO-253 Clinical Trial

The Phase 1b, multicenter, open-label, dose-escalation clinical trial of APTO-253 is designed to assess the safety, tolerability, pharmacokinetics and pharmacodynamic responses and establish the recommended Phase 2 dose and efficacy of APTO-253 as a single agent.  APTO-253 will be administered once weekly, over a 28-day cycle.  The study is expected to enroll up to 20 patients with relapsed or refractory acute myeloid leukemia (AML) and high-risk myelodysplastic syndromes (MDS) patients.  The study is designed to then transition, as appropriate, to single-agent expansion cohorts in AML and MDS, followed by combination studies.  More information can be found at www.clinicaltrials.gov.

About APTO-253

APTO-253 is a clinical-stage, small molecule, targeted therapeutic agent that inhibits expression of the MYC oncogene, leading to cell cycle arrest and programmed cell death (apoptosis) in human-derived solid tumor and hematologic cancer cells. The MYC oncogene is overexpressed in hematologic cancers, including acute myeloid leukemia (AML).  Aptose researchers have reported the ability of APTO-253 to induce cell death, or apoptosis, in multiple blood cancer cell lines including AML, as well as in vitro synergy with various classes of conventional approved and investigational therapies for AML or myelodysplastic syndromes (MDS).  New findings reveal that APTO-253 might also serve certain solid tumor patients with BRCA1/2 mutations, but without causing toxicity to the normal bone marrow functions.

About Aptose

Aptose Biosciences is a clinical-stage biotechnology company committed to developing personalized therapies addressing unmet medical needs in oncology, with an initial focus on hematology.  The company’s small molecule cancer therapeutics pipeline includes products designed to provide single agent efficacy and to enhance the efficacy of other anti-cancer therapies and regimens without overlapping toxicities.  APTO-253, the only clinical stage agent that directly targets the MYC oncogene and inhibits its expression, is in a Phase 1b clinical trial for the treatment of patients with relapsed or refractory acute myeloid leukemia (AML) or high risk MDS.  CG-806 is an oral, first-in-class pan-FLT3/pan-BTK multi-cluster kinase inhibitor being developed to treat AML and certain B cell malignancies. For further information, please visit www.aptose.com.

SOURCE: Aptose