Sionna Therapeutics, Inc., a clinical-stage biopharmaceutical company, researches and develops medicines for the treatment of cystic fibrosis (CF). It develops galicaftor (SION-2222), a transmembrane domain 1 (TMD1)-directed cystic fibrosis transmembrane conductance regulator (CFTR) that has completed Phase 2 trial; navocaftor (SION-3067), a potentiator that has completed Phase 2 trial; SION-109, an intracellular loop 4 directed CFTR corrector that has completed Phase 1 trial; SION-2851, a TMD1-directed CFTR corrector that has completed Phase 1 trial; SION-451, which is nucleotide-binding domain 1 stabilizer in Phase 1 trial; and SION-719, which is nucleotide-binding domain 1 stabilizer in Phase 2a proof-of-concept trial. The company was formerly known as Sling Therapeutics, Inc. and changed its name to Sionna Therapeutics, Inc. in July 2021. Sionna Therapeutics, Inc. was incorporated in 2019 and is headquartered in Waltham, Massachusetts.