Introduction: PATRO Children is a non-interventional, international, longitudinal study of the long-term safety of a recombinant human growth hormone (rhGH; Omnitrope®, Sandoz) in patients requiring this therapy. Here we compare data from participants in the US with the ROW. Methods: The study population includes infants, children and adolescents receiving Omnitrope® therapy according to local prescribing information. All adverse events (AEs) are monitored and recorded for evaluation of rhGH safety. Laboratory values (including glucose metabolism and anti-hGH antibodies) are requested at least once a year. Height standard deviation score (HSDS), height velocity (HV) and HVSDS are calculated using height measurements and country-specific reference tables to evaluate rhGH efficacy. Results: As of September 2018, 294 US patients (including 65.6% GHD, 21.1% ISS, 2.7% SGA) and 6500 ROW patients (including 57.9% GHD, 25.8% SGA, 3.0% ISS) had been enrolled in the study. Mean (± standard deviation [SD]) age at enrollment was 10.44 ± 3.64 years for US patients and 72.8% were male. For ROW, mean ± SD age at enrollment was 8.95 ± 3.90 years and 58.7% were male. Overall, 53.1% (US) and 86.3% (ROW) of patients were rhGH naïve. Mean ± SD Omnitrope® treatment duration was 40.24 ± 17.39 and 38.18 ± 26.89 months in US and ROW patients, respectively; 49.66% (US) and 42.35% (ROW) of patients had completed 3 years’ treatment. Mean ± SD doses at study baseline and after 3 years were 0.0473 ± 0.0144 and 0.0541 ± 0.0289 mg/kg/day in the US group, and 0.0321 (0.0094) and 0.0359 (0.0106) mg/kg/day in the ROW group. In total, 886 AEs were recorded in 194 (66.0%) US patients; 5 AEs in 5 patients were considered treatment-related, and 3 (1.3%) patients discontinued therapy due to an AE. For ROW, 11716 AEs were recorded in 2977 (48.0%) patients, 636 (452 patients) of which were considered treatment-related; 105 (1.7%) discontinued due to an AE. Serious AEs were noted in 14 (4.8%) US patients (19 events) and 738 (11.9%) ROW patients (1429 events). No clinically relevant positive anti-hGH antibody titers have been found after the start of rhGH therapy in patients tested so far. After 3 years, improvement from baseline in HSDS and HVSDS among prepubertal, treatment-naïve GHD patients was similar between the US (+1.34; +3.06) and ROW (+1.35; +3.55) groups. Conclusions: Based on this snapshot of data from the ongoing PATRO Children study, Omnitrope® treatment appears to be similarly well tolerated and effective in patients enrolled from the US and ROW. Some differences between the US and ROW patients are apparent, likely reflecting differences in referral patterns, rhGH treatment practices and approved indications across different regions.