Airway Therapeutics Closes $50 Million Equity Round to Advance Late-Stage Development of Zelpultide Alfa

• PR Newswire

ATLANTA, Aug. 25, 2026 /PRNewswire/ -- , a late-stage clinical biopharmaceutical company developing novel biologic therapies for respiratory, inflammatory, and infectious diseases, today announced the closing of a $50 million equity round to support the continued late-stage clinical development of zelpultide alfa, the Company's novel recombinant human surfactant protein D (rhSP-D).

The E-round consists of $26 million previously raised through a SAFE financing and $24 million through the Company's Series E-2 round. Proceeds will primarily support Airway's completion of the ongoing Phase 2b portion of the Phase 2b/3 clinical trial evaluating zelpultide alfa for the prevention of bronchopulmonary dysplasia (BPD) in very preterm infants, as well as associated chemistry, manufacturing and controls (CMC) and analytical activities required to advance the program.

The Series E-2 round received broad participation from Airway's existing investor base, with approximately 94% of existing investors participating in the round. Participants included Cincinnati Children's and a syndicate of large family offices, who are committed to advancing novel therapies for serious respiratory diseases.

"We are extremely pleased by the strong participation and continued support of our existing investors, with approximately 94% of our current cap table participating in the Series E-2 round, reflecting their confidence in Airway, our team and the potential of zelpultide alfa," said Marc Salzberg, MD, Chairman and Chief Executive Officer of Airway Therapeutics. "With this round, we are well positioned to maintain momentum across our late-stage clinical program as we evaluate zelpultide alfa for the prevention of BPD in very preterm infants, a population with significant unmet medical need and no approved preventive therapies."

"This round further solidifies Airway's financial position as we execute the ongoing Phase 2b/3 clinical trial and prepare for the program's next important development milestones," said Alan S. Wolk, MBA, Chief Financial Officer and Chief Operating Officer of Airway Therapeutics "The proceeds provide us with the capital to support the clinical study as well as the CMC and BLA readiness analytical work necessary to advance zelpultide alfa through late-stage development in a disciplined and efficient manner."

Airway's next major development milestone is the planned interim analysis marking the completion of the Phase 2b portion of the ongoing Phase 2b/3 clinical trial. Results from the interim analysis are expected by the end of the second quarter of 2027.

Zelpultide alfa is a recombinant human surfactant protein D (rhSP-D) precisely engineered to replicate the native protein's full quaternary structure and biological function, incorporating optimized glycosylation through advanced cell line technology. Its therapeutic activity is driven by three key mechanisms: modulation of immune responses to mitigate excessive inflammation, enhancement of pathogen recognition and clearance, and maintenance of surfactant homeostasis to support pulmonary function. As a versatile biologic platform, zelpultide alfa is being developed for patients across all age groups—from preventing bronchopulmonary dysplasia (BPD) in very preterm infants to treating acute and chronic respiratory, inflammatory and infectious conditions in adults.

Zelpultide alfa's lead indication, BPD prevention, is currently progressing through a Phase 2b/3 clinical trial, following a Phase 1b study that demonstrated a favorable safety and tolerability profile.

Airway Therapeutics is a late-stage clinical biopharmaceutical company developing a new class of biologic therapies to redefine the prevention and treatment of respiratory, inflammatory, and infectious diseases. Its lead candidate, zelpultide alfa, is currently in late-stage clinical development for the prevention of bronchopulmonary dysplasia (BPD) in very preterm infants, a condition with no approved preventive therapies. As a platform biologic, zelpultide alfa is also being advanced for broader application across age groups and disease settings, with the goal of improving outcomes for vulnerable patient populations.

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Libba MuziAirway Therapeutics 513-770-9630

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