I went from Trelegy to Breztri and find that the Breztri worked better for me. However, I do not know who designed the inhaler but it is extremely difficult to manipulate and use. I have voiced my concerns to the Rep, via web-site and whoever I can think of. The vessel for administration is terrible and I fear that there are many lost doses simply because of the design of the inhaler. Are you using an spacer with your inhalers....that may ease using it in light of your arthritis. Especially if you used it prior and are now having issues by switching to Trelegy.