ObjectiveTo follow up the participants of the randomized clinical trial Efficacy and Safety of Niaoduqing Particles (?????) for Delaying Moderate-to-Severe Renal Dysfunction, and assess the long-term effects of Niaoduqing Particles on delaying the progression of renal dysfunction.MethodsParticipants, who had previously been randomly assigned to receive Niaoduqing Particles or placebo for 24 weeks (146 cases in each group), were invited to follow-up and all were administered Niaoduqing Particles 5 g thrice daily and 10 g before bedtime for 24 weeks. The primary endpoints were changes in baseline serum creatinine (Scr) and estimated glomerular filtration rate (eGFR) after completion of the open-label treatment period.ResultsAfter the double-blind period, the median (interquartile range) changes in Scr were 1.1 (-13.0-24.1) and 11.7 (-2.6-42.9) mol/L for the Niaoduqing Particle and placebo groups, respectively (P=0.008), and the median changes in eGFRs were-0.2 (-4.3-2.7) and-2.21 (-5.7-0.8) mL center dot min(-1)center dot 1.73 m(-2), respectively (P=0.016). There were significant differences in the double-blind period changes in renal function between groups. After the open-label period, the median changes in Scr were 9.0 (-10.0-41.9) and 17.5 (-6.0-50.0) mol/L for the Niaoduqing Particle and placebo groups according to baseline grouping, respectively (P=0.214), and the median changes in eGFRs were-2.3 (-6.4-1.9) and-3.7 (-7.5-1.1) mL center dot min(-1)center dot 1.73 m(-2), respectively (P=0.134). There were no statistical differences in the open-label period changes in renal function between groups. The eGFR reduction of participants who accepted Niaoduqing Particle treatment for 48 weeks was projected to 2.5 mL center dot min(-1)center dot 1.73 m(-2) per year.ConclusionNiaoduqing Particles appear to have long-term efficacy for patients with moderate-to-severe renal dysfunction. Although there was no statistical difference, the early use of Niaoduqing Paticles seems to ameliorate the worsening of renal function.