Objective: To investigate the efficacy of modified Yinchen Sini Tang in treating patients with acute-on-chronic liver failure (ACLF) characterized by Yin jaundice syndrome. Method: Two hundred and sixty eligible patients with ACLF characterized by Yin jaundice syndrome were randomly divided into the control group (n=130) and the treatment group (n=130). They were respectively given the simple comprehensive western therapy and the combined therapy with modified Yinchen Sini Tang for 8 weeks. Baseline characteristics were compared between both groups before and after the treatment.Before and after treatment

patients' symptoms and signs score

liver function [including alanine aminotransferase (ALT)

total bilirubin (TBIL) and albumin-albumin (ALB)]

primary trait analysis (PTA)

model for end-stage liver disease(MELD) changes were recorded

and traditional Chinese medicine(TCM) syndromes

8-week treatment effect and short-term (12 weeks) differences in prognosis of two groups were compared. Result: The treatment group was significantly superior to the control group in symptom scores (P<0.01). In the overall response rate of TCM symptoms

the treatment group was 87.90%

while the control group was 60.83%

with a significant difference (P<0.05). After treatment

both groups showed improvements in TBIL

ALT

ALB

PTA

MELD scores

the difference was significant (P<0.01). At the 8th week after treatment

the overall response rate in the treatment group were significantly higher than the control group (91.54% VS 53.85%) (P<0.01). At the 12th week

more patients were survived in the treatment group than the control group (P<0.05). Conclusion: Modified Yinchen Sini Tang can relieve clinical symptoms of patients with ACLF characterized by Yin jaundice syndrome and protect the liver

with a superior efficacy than the simple comprehensive western therapy.