The largest time-matched mean QTcF difference versus placebo for the therapeutic dose of corifollitropin alfa was 1.4 ms ( upper limit of 1-sided 95 % confidence interval ( UL 95 % CI ) = 3.4 ms ) , and for the supratherapeutic dose was 1.2 ms ( UL 95 % CI = 3.6 ms ) .