In the ripasudil-latanoprost study , those IOP reductions were -2.2 and -1.8 mm Hg at 9 am for a difference of 0.4 mm Hg ( 95 % CI , -0.0 to 0.9 mm Hg ; P = .06 ) and -3.2 and -1.8 mm Hg at 11 am for a difference of 1.4 mm Hg ( 95 % CI , 0.9-1 .9 mm Hg ; P < .001 ) , respectively .