PREDNOS 2 was a double blind placebo controlled trial done to investigate the use of daily low-dose prednisolone for the treatment of upper respiratory tract infection—related relapses. It evaluated 365 children with relapsing steroid-sensitive nephrotic syndrome with and without background immunosuppressive treatment at 122 pediatric departments in the UK from February 1, 2013, to January 31, 2020. At the beginning of an upper respiratory tract infection, children received 6 days of prednisolone, 15 mg/m2 daily, or matching placebo preparation. Those already taking alternate-day prednisolone rounded their daily dose using trial medication to the equivalent of 15 mg/m2 daily or their alternate-day dose, whichever was greater. The primary outcome was the incidence of first upper respi-ratory tract infection-related relapse. The modified intention-to-treat analysis population comprised 271 children (mean (SD) age, 7.6 (3.5) years; 64.2% male), with 134 in the prednisolone arm and 137 in the placebo arm. The number of patients experiencing an upper respiratory tract infection-related relapse was 56 (42.7%) in the predniso-lone arm and 58 (44.3%) in the placebo arm (adjusted risk difference, 0.02; 95% CI, 0.14 to 0.10; P =0.70). No evidence was found that the treatment effect differed according to background immuno-suppressive treatment. A post hoc subgroup analysis assessing the primary outcome in 54 children of South Asian ethnicity (risk ratio, 0.66; 95% CI, 0.40–1.10) vs 208 children of other ethnicity (risk ratio, 1.11; 95% CI, 0.81–1.54) found no difference in efficacy of intervention in those of South Asian ethnicity (test for interaction P=0.09). The authors concluded that, results of PREDNOS 2 suggest that administering 6 days of daily low-dose prednisolone at the time of an upper respiratory tract infection does not reduce the risk of relapse of nephrotic syndrome in children in the UK and further work is needed to study the inter-ethnic differences in the study response.