Windtree blows towards Lee's Pharma once again, signing new deal

Windtree Therapeutics is heading back to the licensing well, using a familiar bucket to reel in more biobucks.

The biotech is handing over greater China and Asia Pacific rights to Lee’s Pharma for three out of four assets remaining in its pipeline, according to an announcement Wednesday. Lee’s and its affiliate had already signed onto global rights to Windtree’s KL4 surfactant peptide candidate and associated device, AEROSURF, back in 2022. 

The new pact ties up the familiar pair for future China and Asia Pacific development and commercialization of phase 2-stage istaroxime, rostafuroxin and preclinical oral SERCA2a activators. Windtree stands to earn $138.1 million in milestone payments, about $100 million of which Windtree says is tied to the performance of the heart failure platform of assets. There’s no mention of an upfront payment included in the deal.

Lee’s Pharma will be on the hook for all future development, manufacturing, regulatory and commercialization costs of the assets in the region, though Windtree has final say on clinical protocols. 

The star of the deal is istaroxime, which hit a phase 2 goal as a treatment for cardiogenic shock back in April 2022. But biotech’s bear market left the company without enough capital to press ahead with further development alone. The data jumpstarted partnership conversations, however, with Windtree CEO Craig Fraser telling Fierce Biotech shortly after the phase 2 announcement that the news spurred more than a dozen conversations. 

Windtree has previously tested istaroxime in a phase 2 study out of China in patients with heart failure, an indication for which Lee's is now set to embark on a phase 3 trial. Fraser said in a release that he feels the agreement serves “as validation of the significant heart failure market opportunity for istaroxime.”