Aptose Biosciences Inc. (NASDAQ: APTO) dropped 32.01% after the releases of its corporate update highlights on June 11, 2021, focusing on the luxeptinib clinical status. Luxeptinib is the company’s first-in-class oral FLT3 and BTK kinases inhibitor under evaluation for refractory or relapsed acute myeloid leukemia (AML) and r/r B cell malignancies treatment.
Luxeptnib study results consistent with
William G. Rice, Aptose CEO, said that the recent clinical study has demonstrated that luxeptinib can be an active treatment for numerous indications in both myeloid and lymphoid malignancies. He said that the results are consistent with study hypotheses from the company’s preclinical study portfolio. Rice added that they are thrilled to see anti-tumor activity in pretreated and clinically problematic patients. Aptose will continue dosing at higher exposures for extended periods to investigate the potential of luxeptnib.
In the updates provided, the company indicated that the ongoing phase1a/b trial in refractory or relapsed AML finalized the first two 450mg and 600mg dose cohorts and escalated the third 750mg dose cohort. Aptose is planning to escalate doses further and has witnessed no safety events that can hinder dose escalation. Equally, the company attained expected stable PK levels and PD inhibition of target kinases, consistent with a parallel study in different patient populations.
Aptose to expand luxeptnib dose in AML in 2H 2021
Results show that the first two dose cohorts were effective in delivering anti-leukemic activity in several patients. There was a lasting MRD-negative complete response in an FLT3-ITD AML patient that had relapsed following two allogeneic stem cell transplants, previous FLT3 inhibitor therapy, and several lines of chemotherapy. Based on these preclinical and clinical observations, the company expects to select a dose expansion and cohort expansion strategy for AML in 2H 2021.