Short-term clinical outcomes of intranasal stem cell–derived extracellular vesicles in small dogs with tracheal collapse: A pilot study

Tracheal collapse is a common chronic airway disease in small-breed dogs, and conventional medical management often provides limited long-term clinical improvement. Stem cell–derived extracellular vesicles (EVs) have recently emerged as a promising cell-free therapeutic approach because of their anti-inflammatory and immunomodulatory properties. This study aimed to evaluate the safety and preliminary clinical effects of intranasal administration of mesenchymal stem cell–derived extracellular vesicles (MSC-EVs) in dogs with naturally occurring tracheal collapse. Ten client-owned small-breed dogs diagnosed with tracheal collapse were enrolled in this pilot study. MSC-EVs were administered intranasally as a single dose. Clinical evaluations were performed at baseline and at 1 and 4 weeks after treatment. Functional status was assessed using the Canine Karnofsky Score (CKS), and respiratory signs were evaluated using a cough scoring system that included cough duration, interval, intensity, and total cough score. Safety was assessed through physical examinations and owner-reported outcomes. One dog was excluded from statistical analysis due to death associated with concurrent disease. Following MSC-EV administration, CKS improved in five of nine dogs, with CKS increasing from baseline to week 4. Significant improvements were observed in cough interval, cough intensity, and total cough score at both follow-up time points, while cough duration showed a decreasing trend. No treatment-related adverse events were observed. Intranasal administration of MSC-EVs was safe and well tolerated and was associated with improvement in functional status and cough-related clinical signs in dogs with tracheal collapse. These findings suggest that MSC-EV therapy may represent a promising minimally invasive treatment option for chronic canine airway disease.