The present invention is directed to a combination or a kit comprising a prostaglandin analog and an adenosine receptor A1 agonist and to a method of reducing intraocular pressure (IOP) in a subject using such combination or kit. In one embodiment, the prostaglandin analog is latanoprost and the adenosine receptor A1 agonist is Compound A, ((2R,3S,4R,5R)-5-(6-(cyclopentylamino)-9H-purin-9-yl)-3,4-dihydroxytetrahydrofuran-2-yl)methyl nitrate, having the structure,