Treatment with vitamin D3 did not alter the rate of first treatment failure during 28 weeks ( 28 % [ 95 % CI , 21 % -34 % ] with vitamin D3 vs 29 % [ 95 % CI , 23 % -35 % ] with placebo ; adjusted hazard ratio , 0.9 [ 95 % CI , 0.6-1 .3 ] ) .