Sionna Therapeutics snagged the exclusive worldwide license to three of AbbVie’s cystic fibrosis drug candidates as the biotech aims to beef up its work in the genetic condition and fill gaps not covered by Vertex, the field’s leading drugmaker.
As part of the pact announced Tuesday morning, Sionna is paying a “small upfront,” CEO Mike Cloonan said in an interview with Endpoints News. AbbVie also gets an equity investment in the Boston-based biotech on top of potential late-stage development and commercial biobucks and royalties of undisclosed size.
The deal arrives four months after Sionna disclosed a $182 million Series C that will take it through 2026, Cloonan said.
AbbVie is handing over two candidates that have been through Phase 2: the TMD1-directed CFTR corrector ABBV-2222 (also known as galicaftor) and the CFTR potentiator ABBV-3067 (also known as navocaftor). Also in the deal is another TMD1-directed asset, the Phase 1-stage ABBV-2851.
A dual combination of ABBV-2222 and ABBV-3067 was previously tested alongside a C2 corrector, ABBV-119, in a Phase 2. The triplet therapy did not pass the bar, AbbVie said in April 2022, but the dual combination portion “performed well,” according to remarks made at the time by then-chief scientific officer Tom Hudson. Galapagos originally developed ABBV-2222 and ABBV-3067.
Weaving into Sionna’s pipeline
Sionna’s pipeline of experimental small molecules targets the most common genetic mutation for patients with the life-threatening condition: ΔF508.
About 85% to 90% of people have at least one copy of that mutation, Sionna chief medical officer Charlotte McKee said in an interview. “NBD1 is the domain in which that ΔF508 actually lives.”
Charlotte McKee“Vertex has very successfully, to this point, found drugs that bind around NBD1,” said McKee, who joined Sionna in 2021 after six years at Vertex, including a role as VP of CF clinical development. “The current modulators stabilize and bind around this domain, but they don’t directly stabilize, so you’ve still got this critical place where the thing that goes wrong is actually living. That still causes a significant amount of instability and dysfunction that’s being left on the table at this point with the current modulators.”
“Nobody’s been able to crack that code,” Cloonan said, referring to bringing NBD1 into the clinic.
Sionna doesn’t plan to immediately bring forward all three of the AbbVie assets. Sionna said it will choose one of the AbbVie assets to combine with its ICL4-targeted SION-109 and one of its NBD1 stabilizers. SION-109 is set to finish a Phase 1 later this year, and its lead NBD1 program, SION-638, has completed Phase 1. Two more NBD1 programs, SION-451 and SION-719, are entering Phase 1 this summer and are expected to have data by the end of 2024 or early 2025, Cloonan said. After that time, the company will sift through the results to determine next steps.
For the AbbVie assets that aren’t selected for the combination regimen, Sionna will retain them as “lifecycle management plays if we need additional efficacy down the line,” Cloonan said. “Or, if for some reason something happens to one of those compounds, you have a ready-made backup ready to go off the shelf.”