Sionna Therapeutics, Inc. is a clinical-stage biopharmaceutical company. The Company is focused on researching and developing novel medicines for cystic fibrosis. It is advancing a pipeline of small molecules engineered to correct the defects caused by the F508del genetic mutation, which resides in nucleotide-binding domain 1 (NBD1). It is conducting ongoing Phase I trials of its two highly potent NBD1 stabilizers, SION-719 and SION-451, evaluating the safety, tolerability and pharmacokinetic (PK) profile of single and multiple ascending doses in healthy subjects. It is also developing a portfolio of cystic fibrosis transmembrane conductance regulator (CFTR) modulators designed to work synergistically with its NBD1 stabilizers to improve CFTR function. Its portfolio also includes Galicaftor (SION-2222) and SION-2851, which are TMD1-directed CFTR correctors; SION-109, an ICL4-directed CFTR corrector, and Navocaftor (SION-3067), is a clinical-stage potentiator of CFTR gating activity.