Pulmonary fibrosis—also known in technical terms as idiopathic pulmonary fibrosis (IPF)—is a rare but life-threatening disease. It causes scarring of the connective tissue between the functional tissue of the lungs, leading to increasing shortness of breath. Current treatments can slow the progression of fibrosis, but cannot cure it. The average life expectancy after diagnosis is only four to six years. New therapies are therefore urgently needed.