Complex sentence: Roflumilast, cilomilast, and phosphodiesterase 4 inhibitors act as a bronchodilator and as an anti-inflammatory, shows promise in decreasing the rate of exacerbations, but do not appear to change a persons quality of life.
Split into simpler sentences: Roflumilast, cilomilast, and phosphodiesterase 4 inhibitors act as a bronchodilator and as an anti-inflammatory. They show promise in decreasing the rate of exacerbations, but do not appear to change a persons quality of life.