Astria Therapeutics announces initial results from STAR-0310 trial

Astria Therapeutics (ATXS) announced initial results from the Phase 1a trial of STAR-0310, a YTE half-life extended monoclonal antibody antagonist of OX40, in healthy subjects. STAR-0310 demonstrated a best-in-class half-life of up to 68 days, consistent with administration every six months, durable cytokine inhibition, and was well-tolerated with no antibody-dependent cellular cytotoxicity-related side effects. STAR-0310 exhibited dose-proportional increases in concentrations, with slow clearance and an extended half-life of up to 68 days. STAR-0310 was observed to be well-tolerated at all dose levels, with no serious treatment-emergent adverse events or discontinuations. Mild, treatment-related TEAEs were observed in seven participants receiving STAR-0310 that resolved without intervention. No fever or chills were observed, consistent with the preclinical observation that STAR-0310 exhibits low ADCC activity. Biomarker results showed that a single, subcutaneous injection of STAR-0310 resulted in sustained and durable ex vivo cytokine inhibition for the duration of the observation period of 16 to 20 weeks, supporting target engagement and suggesting that STAR-0310 is modulating a broad spectrum of immune pathways beyond Th-2 for a long duration of effect, and could benefit a broader patient population than existing approved biologics.