Molecular Partners present updated data from Phase 1 trial of MP0317

Molecular Partners will present additional positive data from its Phase 1 study of MP0317 in patients with advanced solid tumors at the 2023 Annual Meeting of the Society for Immunotherapy of Cancer, being held November 1-5 in San Diego, California. MP0317 is a CD40 agonist designed to activate immune cells specifically within the tumor microenvironmen by anchoring to fibroblast activation protein. This update, based on data from 46 patients, corroborates earlier reported findings of MP0317-induced CD40 activation and related remodeling of the TME. The detection of MP0317 in tumor biopsies is associated with an increase in CD40-mediated re-programming of immune cells illustrated by IFNg production and dendritic cell maturation within the TME. Elevation of serum levels of CXCL10, an effector chemokine downstream of IFNg signaling, and changes in soluble biomarkers post-MP0317 treatment support these findings. To date, one patient achieved a partial response and stable disease was observed in eight additional patients. MP0317 continues to display a favorable safety profile across all dosing cohorts, with limited systemic inflammation-related adverse reactions compared to other CD40 agonists. Dose-limiting toxicity was reported in only one patient to date, at the highest planned MP0317 dose of 10 mg/kg administered Q3W. The positive results of this fully enrolled Phase 1 study in patients with refractory/relapsed tumors support continued clinical evaluation of MP0317 and potential investigation in combination studies. The Company expects to share final results of this study in 2024. This ongoing first-in-human Phase 1, open-label, dose-escalation study assesses the safety and tolerability as well as pharmacokinetics/pharmacodynamics and preliminary antitumor activity of MP0317 monotherapy in patients with advanced solid tumors known to express FAP and CD40. Recruitment for the dose-escalation portion of the study is complete, with 46 patients enrolled in the Netherlands and France across nine dosing cohorts. Patients received MP0317 at doses of 0.03-10 mg/kg in every-3-weeks or weekly schedules.