Few randomized studies have assessed recovery from rocuronium- or vecuronium-induced moderate or deep neuromuscular blockade with sugammadex in pediatric participants. To assess sugammadex for reversal of neuromuscular blockade in pediatric participants. This was a randomized, phase IV, active comparator-controlled, double-blind study. Participants aged 2 to <17years, under moderate or deep neuromuscular blockade, were administered sugammadex (2 or 4mg/kg) or neostigmine (50µg/kg; for moderate neuromuscular blockade only). Predefined adverse events of clinical interest, including clinically relevant bradycardia, hypersensitivity, and anaphylaxis, were monitored. The primary efficacy endpoint was time to recovery to a train-of-four ratio of ≥0.9 in participants receiving sugammadex 2mg/kg versus neostigmine for reversal of moderate neuromuscular blockade, analyzed by analysis of variance adjusted for neuromuscular blocking agent and age. Of 288 randomized participants, 272 completed the study and 276 were included in the analyses. Clinically relevant bradycardia was experienced by 2.0%, 1.6%, and 5.9% of participants in the sugammadex 2mg/kg, sugammadex 4mg/kg, and neostigmine groups, respectively. No hypersensitivity or anaphylaxis events were observed. Recovery to a train-of-four ratio of ≥0.9 with sugammadex 2mg/kg was faster than neostigmine (1.6min, 95% CI 1.3 to 2.0 vs. 7.5min, 95% CI 5.6 to 10.0; p<.0001) and was comparable to sugammadex 4mg/kg (2.0min, 95% CI 1.8 to 2.3). Pediatric participants recovered from rocuronium- or vecuronium-induced moderate neuromuscular blockade significantly faster with sugammadex 2mg/kg than with neostigmine. Time to reversal of deep neuromuscular blockade with sugammadex 4mg/kg was consistent with that of moderate neuromuscular blockade reversal. No meaningful differences in clinically relevant bradycardia, hypersensitivity, or anaphylaxis were seen with sugammadex vs neostigmine. These results support the use of sugammadex for reversal of moderate and deep rocuronium- and vecuronium-induced neuromuscular blockade in patients aged 2 to <17years. NCT03351608/EudraCT 2017-000692-92.