Molecular Partners Presents Updated Data from Ongoing Phase 1/2a Trial of MP0533 in AML at ASH Annual Meeting

• Poster outlines clinical benefit with acceptable safety profile across 9 tested dosing regimens
  
  
• Accelerated step-up dosing and higher dosing frequency is feasible and results in increased exposure
  
  
• Six of eight responders presented with low bone marrow blast counts at baseline, supporting further investigation in this patient population most likely to benefit from MP0533
  

ZURICH-SCHLIEREN, Switzerland and CONCORD, Mass., Dec. 07, 2025 (GLOBE NEWSWIRE) -- Ad hoc announcement pursuant to Art. 53 LR Molecular Partners AG (SIX: MOLN; NASDAQ: MOLN), a clinical-stage biotech company developing a new class of custom-built protein drugs known as DARPin therapeutics (“Molecular Partners” or the “Company”), has today announced it will present updated data from a Phase 1/2a trial of the multispecific T-cell engager MP0533 in patients with acute myeloid leukemia (AML) in a poster at the 67th American Society of Hematology (ASH) Annual Meeting and Exposition, taking place December 6-9, 2025, in Orlando, Florida.

The poster outlines the latest results of this multicenter, open-label study evaluating MP0533 for the treatment of patients with relapsed/refractory (R/R) AML and myelodysplastic syndrome (MDS)/AML (ClinicalTrials.gov: NCT05673057). Data from cohorts 8 and 9 show that densified MP0533 dosing appears tolerable and leads to markedly improved serum exposure in treatment cycle 1, with encouraging preliminary antitumor activity.

“The results in patients with higher frequency dosing regimens of MP0533 are very encouraging. I am happy to see the clinical benefit of MP0533 in a mutation-agnostic manner in R/R AML patients, in particular those with lower disease burden. The data indicate that MP0533 has the potential to significantly improve treatment options for patients with AML and I support investigating MP0533 in a Phase 2 setting to confirm its safety and activity in earlier lines as consolidation addition to existing backbones,” said Prof. Courtney DiNardo, M.D., Division of Cancer Medicine, The University of Texas MD Anderson Cancer Center, Houston, Texas, and co-chair of the MP0533 dose escalation review committee (DERC).