A drug product comprising: a dry powder inhalation device containing one or more pharmaceutical compositions present therein, wherein the one or more pharmaceutical compositions comprise active ingredients (I) 4-{(1 R )-2-[(6-{2-[(2,6-dichlorobenzyl)oxy]ethoxy}hexyl)amino]-1-hydroxyethyl}-2-(hydroxymethyl)phenol, or a salt thereof, and (II) (6±,11ß,16±,17±)-6,9-difluoro-17-{[(fluoromethyl)thio]carbonyl}-11-hydroxy-16-methyl-3-oxoandrosta-1,4-dien-17-yl 2- furancarboxylate or a solvate thereof; a hygroscopic material; and a package which encompasses the dry powder inhalation device and the hygroscopic material defining an enclosed volume therein; wherein each of the active ingredients (I) and (II) are present in the same or different pharmaceutical compositions, and wherein the enclosed volume within the package exhibits a Relative Humidity of from 20% to 40%.