BOSTON, MA, USA I May 22, 2023 I Pieris Pharmaceuticals, Inc. (Nasdaq:PIRS), a clinical-stage biotechnology company advancing novel biotherapeutics through its proprietary Anticalin® technology platform for respiratory diseases, cancer, and other indications, announced the presentation of preclinical data from the Company’s inhaled Jagged-1 targeting program, PRS-400, at the annual American Thoracic Society (ATS) International Conference being held in Washington, D.C. May 19-24, 2023. The poster presentation will be available on May 22, 2023, from 2:15 PM to 4:15 PM (Session B107, 711) and demonstrates that Pieris’ lead candidate has reached desired in vitro and ex vivo potency goals while also demonstrating in vivo proof of concept when locally administered to the lung, showing the promise of PRS-400 as an inhaled therapy for patients with muco-obstructive lung diseases. A copy of the poster can be viewed HERE.

PRS-400 is a potentially novel intervention for mucus hypersecretion as it both inhibits the formation of mucus-secreting cells and stimulates the creation of mucus-clearing cells, thereby addressing mucus-driven diseases at the root. Jagged-1, one of five human Notch receptor ligand members, is involved in cell fate specification in the lung, and aberrant Jagged-1/Notch signaling drives a pro-secretory cell phenotype leading to mucus hypersecretion. As the Notch signaling pathway has fundamental roles in multiple other organs, a systemically administered intervention may have undesirable side effects. PRS-400 offers a potential solution to this challenge when administered locally to the lung by targeting Jagged-1 expressed on lung epithelial cells and avoiding undesired target engagement peripherally.

As shown in the poster presentation, Pieris’ lead candidate reduced mucin expression and differentiation of goblet (mucus-producing) cells under pro-inflammatory conditions ex vivo. Further, the lead candidate dose-dependently reduced mucin expression and drove the differentiation of mucus-secreting goblet cells to a ciliated cell phenotype in both prophylactic and therapeutic models of disease in vivo. Additional preclinical studies are ongoing to support the advancement of PRS-400 to clinical development, with development candidate nomination anticipated in the second half of this year.

“The localized administration of an inhaled Anticalin therapeutic candidate targeting Jagged-1 has the potential to address mucus dysregulation, an underlying pathogenic driver of many serious lung diseases,” said Shane Olwill, Ph.D., Chief Development Officer of Pieris. “This program is a first-in-class opportunity offering the potential for patients to exit the vicious cycle of mucus hypersecretion, inflammation and infection observed in chronic airway diseases, and we are highly encouraged with these data.”

About PRS-400:

PRS-400 is an inhaled Anticalin protein targeting Jagged-1 with potential in a wide range of respiratory diseases driven by mucus hypersecretion. PRS-400 is designed to exert clinical activity by disrupting mucus-mediated pathology in the airways, while minimizing systemic target exposure outside the lungs. PRS-400 is advancing toward development candidate nomination later this year.

About Pieris Pharmaceuticals:

Pieris is a clinical-stage biotechnology company that combines leading protein engineering capabilities and deep understanding into molecular drivers of disease to develop medicines that drive local biology to produce superior clinical outcomes for patients. Our pipeline is focused on inhalable Anticalin proteins to treat respiratory diseases and locally-activated bispecifics for immuno-oncology. Proprietary to Pieris, Anticalin proteins are a novel class of therapeutics validated in the clinic and by strong partnerships with leading pharmaceutical companies. For more information, visit

SOURCE: Pieris Pharmaceuticals