Sionna Therapeutics on Wednesday announced it raised another round of funding as the company looks to challenge Vertex Pharmaceuticals’ dominant cystic fibrosis business.
Pictured: A young boy with an oxygen mask/iStock, Anastasia Dobrusina
Massachusetts-based Sionna Therapeutics announced Wednesday that it has capped off another funding round of $182 million in a Series C raise as the startup targets market leader Vertex Pharmaceuticals in the cystic fibrosis space.
According to the biotech, the latest injection of funds is meant to support the development of its small molecules that are aiming to restore the function of the cystic fibrosis (CF) transmembrane conductance regulator (CFTR) protein by stabilizing the first nucleotide-binding domain (NBD1).
The Series C, described by Sionna as upsized and oversubscribed, was led by Enavate Sciences with new investors including Perceptive Advisors and Viking Global Investors. Existing investors such as OrbiMed, RA Capital, TPG’s The Rise Fund, Atlas Venture, the Cystic Fibrosis Foundation and Q Healthcare Holdings also participated. The biotech in 2022 raised $111 million in a Series B.
“We have deep experience in CF and a sharp focus on advancing the development of novel small molecules targeting NBD1 and complementary modulators that enable the potential for full restoration of CFTR function for most people living with CF,” Sionna CEO Mike Cloonan said in a statement. “We are encouraged by the strong interest and validation from the excellent investors in our upsized Series C financing.”
Cloonan also noted that the funds from the raise will allow the biotech to execute its clinical development plan with funds through 2026.
Sionna has shown preclinical data showing its NBD1 stabilizers can restore ΔF508-CFTR maturation and function when combined with modulators. A Phase I trial of its candidate SION-638 has found dosing amounts that are “generally safe” and well tolerated.
The biotech is also going forward with two other NBD1 stabilizers, SION-451 and SION-719, and plans to start clinical trials with both in 2024. For its SION-109 compound, which targets NBD1s interface with the CFTR intracellular loop 4 region, a Phase I began in January 2024.
However, Sionna faces stiff competition in the cystic fibrosis space, where Vertex is the dominant player in cystic fibrosis. Vertex posted positive data in February 2024 from a Phase III program of its investigational cystic fibrosis treatment called Vanza, which heads for the regulators later this year.
Intellia Therapeutics and ReCode Therapeutics also announced last month that both companies plan to leverage their respective technologies to develop new medicines to target cystic fibrosis.
Tyler Patchen is a staff writer at BioSpace. You can reach him at tyler.patchen@biospace.com. Follow him on LinkedIn.