The European Commission requested a scientific opinion from the European Food Safety Authority (EFSA). This opinion concerned the safety and efficacy of a feed additive named NICACOX®. This additive contains the active substance nicarbazin and serves as a coccidiostat. Its purpose is to protect chickens for fattening and chickens reared for laying. The FEEDAP Panel, part of EFSA, concluded that NICACOX® is safe for these chickens. Safety is ensured when used at concentrations up to 80 mg nicarbazin per kilogram of complete feed. The product should be administered during the first 21 days of the chickens' lives. This opinion confirms the suitability of the additive for the mentioned poultry categories.