Sionna Therapeutics Inc. reported a net loss of $20.3 million for the third quarter of 2025, compared to a net loss of $25.4 million in the third quarter of 2024. Research and development expenses were $16.0 million, down from $24.6 million in the prior year period, mainly due to one-time charges recognized in the previous year. General and administrative expenses rose to $7.8 million from $3.4 million, primarily due to increased personnel-related costs, professional fees, and stock-based compensation. The company held $325.0 million in cash, cash equivalents, and marketable securities as of September 30, 2025, and expects this to fund operations into 2028. During the period, Sionna initiated a Phase 2a trial of SION-719 in cystic fibrosis, completed a drug-drug interaction study, and began a Phase 1 trial evaluating SION-451 in combination regimens. Topline data from both trials are anticipated in mid-2026. In September 2025, Caroline Stark Beer was appointed Chief Business Officer.