Aptevo Therapeutics announced new clinical data from its ongoing Phase 1b/2 RAINIER trial evaluating mipletamig, a first-in-class CD123 x CD3 bispecific antibody, for newly diagnosed Acute Myeloid Leukemia (AML) patients unfit for intensive chemotherapy. The mipletamig triplet therapy delivered remissions in 85% of evaluable frontline AML patients across two trials.
This 85% remission rate significantly exceeds results from competitor studies, including those achieved in the Viale A trial that evaluated venetoclax and azacitidine (ven/aza) as doublet therapy. The mipletamig combination also enabled a rare pathway to transplant for a previously ineligible unfit patient, highlighting its transformative potential.
The safety profile of mipletamig remains strong, with no dose-limiting toxicities observed among evaluable patients and no cytokine release syndrome (CRS) reported in the ongoing RAINIER trial. This favorable safety profile, combined with compelling efficacy, supports mipletamig's potential as a significant addition to standard of care in frontline AML. Cohort 3 is nearing full enrollment at the highest dose level evaluated to date.
The content on BeyondSPX is for informational purposes only and should not be construed as financial or investment advice. We are not financial advisors. Consult with a qualified professional before making any investment decisions. Any actions you take based on information from this site are solely at your own risk.