Sionna Therapeutics, a Phase 1 biotech developing novel therapies for cystic fibrosis, raised $191 million by offering 10.6 million shares at $18, the high end of the range of $16 to $18. The company offered 1.8 million more shares than anticipated.
Sionna is developing therapies that normalize the function of the cystic fibrosis transmembrane conductance regulator (CFTR) protein as a treatment for CF patients. The company aims to restore CFTR function to as close to normal as possible by directly stabilizing CFTR’s nucleotide-binding domain 1 (NBD1), a different approach than the currently-approved CFTR modulator therapies marketed by Vertex Pharmaceuticals (Nasdaq: VRTX). Vertex currently markets all five approved CFTR modulators, which generated about $10 billion in sales in 2023, and Sionna emphasizes that its Chief Medical Officer previously served as VP of Cystic Fibrosis at Vertex. Sionna is currently conducting Phase 1 trials for its two lead NBD1 stabilizer candidates, and expects to begin Phase 2a trials in the 2H25. It is also in Phase 1 and 2 trials for a portfolio of complementary CFTR modulators, several of which are in-licensed from AbbVie.
Sionna Therapeutics plans to list on the Nasdaq under the symbol SION. Goldman Sachs, TD Cowen, Stifel, and Guggenheim Securities acted as joint bookrunners on the deal.
