• Aptevo Therapeutics reported new interim results from RAINIER, its Phase 1b dose-optimization study of mipletamig with venetoclax, azacitidine in frontline acute myeloid leukemia, with Phase 2 dose selection targeted for 2026.
• Across 31 evaluable patients through Cohort 5, responses and overall clinical benefit continued to compare favorably with historical outcomes for venetoclax with azacitidine alone.
• Safety remained favorable in the expanding dataset, supporting continued dose escalation into final cohorts intended to complete dose selection package.
• Trial remained on track to finish dose optimization in 2026, positioning program for planned Phase 2 regulatory interaction.

Disclaimer: This news brief was created by Public Technologies (PUBT) using generative artificial intelligence. While PUBT strives to provide accurate and timely information, this AI-generated content is for informational purposes only and should not be interpreted as financial, investment, or legal advice. Aptevo Therapeutics Inc. published the original content used to generate this news brief via ACCESS Newswire (Ref. ID: 202605060805ACCESSWRNAPR_____1164140) on May 06, 2026, and is solely responsible for the information contained therein.