A Dual Time Window-driven Strategy to Optimize Primary Biliary Cholangitis Treatment via Alkaline Phosphatase...

The current criterion of biochemical response to ursodeoxycholic acid in primary biliary cholangitis is an alkaline phosphatase (ALP) level of ≤1.67 × the upper limit of normal (ULN) after 12 months of treatment. However, a proportion of patients who meet this parameter may still progress to liver decompensation. This study aimed to optimize the clinical management of primary biliary cholangitis by (1) establishing ALP normalization as a core treatment target, (2) identifying early intervention windows, and (3) developing risk stratification criteria.

This multicenter retrospective study included an internal cohort and an external validation cohort. We assessed the prognostic impact of ALP normalization with Kaplan-Meier and Cox regression. Sankey diagrams and segmented Poisson regression analysis mapped dynamic risk transitions to identify critical intervention windows. Predictive performance (sensitivity/specificity/positive predictive value/negative predictive value [NPV]) of Mayo, Paris II, and Toronto criteria for 12-month ALP normalization was compared.

Patients achieving ALP normalization showed significantly higher complication-free survival versus those with ALP 1.0-1.67 × ULN (89.8% vs. 79.8%; P = 0.016). Segmented Poisson regression identified significant change points at 3.73 and 5.5 months for high-to-medium and medium-to-low risk transitions, respectively. Failure to meet the Toronto criteria at month 3 predicted non-normalization with 95% NPV, whereas Paris II criteria at month 6 provided optimal specificity (73%) for identifying patients who failed to achieve ALP normalization.

ALP normalization significantly improves clinical outcomes. Two subgroups demonstrate low normalization probability and warrant early intervention: (1) patients with ALP ≥ 1.67 × ULN after 3 months and (2) those not meeting Paris II criteria by month 6.