Sionna Therapeutics has quickly found a use for some of its $182 million series C haul, inking a deal with AbbVie to add three clinical-phase candidates to its burgeoning pipeline of cystic fibrosis prospects.
Boston-based Sionna has established itself as a potential threat to Vertex’s iron-grip on the cystic fibrosis market by advancing programs directly targeting correction of NBD1. The biotech has identified NBD1 correction as a way to fully restore CFTR function in patients with the most common mutation of the key cystic fibrosis protein. But it has also recognized combinations may be the route to the best results.
Sionna fast tracked its combination ambitions Tuesday by picking up a trio of molecules from AbbVie. The acquired portfolio includes two midphase compounds, the CFTR corrector ABBV-2222 and the CFTR potentiator ABBV-3067.
AbbVie studied ABBV-2222 and ABBV-3067, molecules respectively also called galicaftor and navocaftor, in combination with a C1 or C2 inhibitor in a midphase clinical trial. However, neither combination lived up to AbbVie’s expectations, prompting the company to stop the study and ax its cystic fibrosis program. AbbVie expanded in cystic fibrosis by paying Galapagos $45 million upfront in 2018.
Sionna has also picked up the rights to a phase 1 corrector, ABBV-2851. The biotech said ABBV-2222 and ABBV-2851 are correctors directed at TMD1, one of the CTFR protein function domains. Sionna has its own TMD1-directed corrector, SION-676, in preclinical development, plus an ICL4-targeted candidate, SION-109, in phase 1.
The expansion of the pipeline gives Sionna a choice to make. Pairing Sionna’s NBD1 stabilizers with any one of SION-109 and the three ex-AbbVie assets delivered better efficacy than the standard of care in a cystic fibrosis assay, the biotech said. Sionna will prioritize advancing one of the four compounds in a dual combination with its most advanced NBD1 stabilizer.
AbbVie parted company with the assets in return for an upfront payment, an equity investment in Sionna and a chance to receive late-stage development and commercial milestones and royalties. Neither party has disclosed the size of the deal.