Molecular Partners presents new preclinical data on Radio-DARPin and Switch-DARPin programs at AACR 2025

Core Insights - Molecular Partners AG presented three posters at the AACR Annual Meeting 2025, showcasing advancements in their DARPin therapeutics, particularly in the context of small cell lung cancer and solid tumors [1][2][8] Group 1: Radio-DARPin Programs - The first poster highlighted positive IND-enabling data for MP0712, a Radio-DARPin targeting DLL3, which is on track to provide initial clinical data in the second half of 2025 [1][2][8] - The second poster presented initial preclinical data on a Pb-based Radio-DARPin targeting mesothelin (MSLN), indicating substantial uptake in MSLN-positive tumors with limited accumulation in other organs [1][2][4] - MP0712 demonstrated high tumor uptake and a favorable safety profile in mouse models, with efficacy and tumor reduction correlating with DLL3 expression levels [3][4] Group 2: T Cell Engager Program - The third poster included preclinical proof-of-concept data on a logic-gated CD3 Switch-DARPin T cell engager, which activates T cells specifically in the presence of tumor-associated antigens, enhancing tumor specificity [5][8] - The Switch-DARPin approach allows for CD2 co-stimulation, leading to sustained T cell activation and preventing dysfunction, with significant tumor regression observed in mouse models [5][8] Group 3: Strategic Partnerships - Molecular Partners is co-developing the Radio-DARPin programs with Orano Med, emphasizing the strategic partnership's role in advancing their therapeutic innovations [2][8] - The company is leveraging the unique properties of DARPins to selectively bind to tumor targets while minimizing off-target effects, particularly in the context of MSLN-targeted therapies [4][8]