Pulmonary Fibrosis Clinical Study

Pulmonary fibrosis (PF) is a devasting disease that affects all dogs with the West Highland White Terrier being the most commonly affected breed. Similar to people, PF causes progressive respiratory failure and ultimately death. There is no treatment currently available that slows or reverses PF. Diagnosis is made by clinical signs of tachypnea and respiratory distress and may be confirmed with either a high-resolution CT scan or by way of a lung biopsy. Dogs commonly develop secondary pulmonary hypertension. A multitude of investigations into the pathogenesis of PF have explored potential causes and avenues for treatment. Over the last 10 years, abnormal deposition of extracellular matrix (ECM) has been recognized as a crucial event in the pathogenesis of fibrosis. Extracellular matrix is the non-cellular component of cells and tissue. Excessive ECM is linked to the development of organ fibrosis. It is suggested that inhibiting excessive extracellular matrix formation may block the progression of pulmonary fibrosis. Hymecromone as an oral medication that is used to inhibit extracellular matrix and has been used in people for many years with a favorable safely profile for treatment of a variety of diseases. The primary goal of this project is to determine if hymecromone (4MU) therapy is effective in improving or stabilizing PF and pulmonary hypertension in affected WHWTs. A preliminary study established that 4MU was safe and well-tolerated in dogs, as expected. This trial is designed as a pragmatic trial to determine both potential efficacy of the medication and also to evaluate the potential for widespread recruitment of affected westies for further clinical trials.