I have COPD and have used several medications (and for five years have used a CPAP machine at night for sleep apnea). I've now been on Trelegy as my main COPD med for well over a year. it's been by far the best medication I've ever used. No side effects, easy once a day dosing. And my pulmonologist is happy with the state of my lungs, which appear stable or slightly improved on Trelegy. I do wish it cost less; my insurance covers most of it, but not everyone is so fortunate.