NASH Progression Rates Based on Fibrosis and Inflammation (NAS): A Paired Biopsy Analysis From a Natural History Cohort in the US.

Challenge

Economic models for NASH therapies required state transition probabilities based on both fibrosis stage progression and disease activity (NAS), but real-world data characterizing both dimensions simultaneously from paired biopsies were essentially unavailable, limiting model accuracy.

Solution

Paired liver biopsy data from TARGET-NASH were used to estimate annual transition probabilities between fibrosis stages and NAS categories in biopsy-confirmed NASH patients, using multinomial logistic regression to generate model-ready transition matrices.

Impact

Providing the first real-world paired biopsy transition probability estimates stratified by both fibrosis and inflammation enables more accurate health economic models for NASH, directly supporting payer value dossiers and informing health technology assessment submissions for NASH therapies.