Windtree's hypertension med snarled in Catch-22 as hunt for partners comes up dry

Despite a two-year search for licensing partners for its hypertension med, Windtree Therapeutics has found itself in a Catch-22 situation that means development of the drug is stalled for the time being.

Windtree put rostafuroxin, a selective antagonist of adducin polymorphisms and endogenous ouabain, through phase 2 trials with the aim of it becoming one of the first hypertension drugs on the market. But after concluding that the drug would sit uneasily at the biotech, the company began a hunt for potential partners in 2021 to find "the right kind of strategic fit" to take the asset forward.

In an end-of-year report (PDF) filed with the Securities and Exchange Commission (SEC) June 30, Windtree said the feedback from potential licensing partners has been that “there is a need for an additional phase 2 clinical trial to demonstrate efficacy in patients with treatment-resistant hypertension.”

The catch is that the biotech’s won’t conduct any additional phase 2 trials until a partner or funder is already signed up. Windtree blamed “current macroeconomic conditions” for making it harder to secure the funding needed for the requested additional phase 2 study.

Money is indeed tight at the biotech, which ended March with just $4.2 million in cash and equivalents. However, the company has since raised $10.8 million from a public offering of common stock in April.

Without someone else fronting the cash or Windtree itself giving ground, it’s hard to see where rostafuroxin goes from here. In the meantime, the biotech will continue to hunt for a pharma that’s willing to buy into the therapy without first seeing extra data. Specifically, Windtree is looking for “one or more larger companies that have an interest in and/or operate in the very large and broad anti-hypertension market.”

In last week’s SEC filing, Windtree pointed to the most recent study of rostafuroxin, a phase 2b study that demonstrated efficacy in Caucasian patients with treatment-naïve hypertension. However, while those positive results had come from the Italian portion of the trial, a separate part of the study conducted in China produced a “minimal” blood pressure response in Chinese patients, the company acknowledged.

Any money made from eventually licensing rostafuroxin will be reinvested in Windtree’s core programs, the company said. After a portfolio reshuffle last year that saw the biotech out-license its Aerosurf drug/device combo for preterm infants with respiratory distress syndrome to a pair of Hong Kong-based pharmas, Windtree remains focused on lead asset istaroxime. The biotech is planning an extension to a phase 2 study in cardiogenic shock, where the candidate has already demonstrated success.