Among patients with BRAF wild-type tumors , the rate of confirmed objective response was @ % ( @ of @ patients ) in the group that received both ipilimumab and nivolumab ( combination group ) versus @ % ( @ of @ patients ) in the group that received ipilimumab and placebo ( ipilimumab-monotherapy group ) ( P < @ ) , with complete responses reported in @ patients ( @ % ) in the combination group and no patients in the ipilimumab-monotherapy group .