Aptevo Stock Gains on Encouraging Single-Agent Activity for APVO436 In Leukemia Patients

Aptevo Therapeutics Inc APVO has announced positive results from Phase 1 dose-escalation trial evaluating lead ADAPTIR candidate, APVO436, for acute myeloid leukemia and myelodysplastic syndromes (AML/MDS).
The study met its primary endpoint of identification of an active dose level for advanced studies.
The Company plans to submit the data for publication later this year.
Of seven evaluable relapsed AML patients treated in Cohort 6, four showed stabilization of their leukemias.
Of those four patients with disease stabilization, three patients lived over 246 days, over 261 days, and over 281 days, respectively, and one progressed after a month.
Two relapsed AML patients, who experienced stabilization of their leukemia, achieved partial remission and subsequently a complete remission.
No partial or complete remissions have been observed at APVO436 dose levels either lower or higher than the Cohort 6 dose level.
APVO436 was generally well tolerated and demonstrated a favorable side effect profile, including the absence of severe or prolonged neutropenia, an often serious condition associated with CD123-targeting therapies.
Price Action: APVO shares are up 9.7% at $27.71 during the market session on the last check Wednesday.