Prospective evaluation of ethnicity and HBV genotype in predicting off-treatment outcomes after nucleos(t)ide analogue cessation: results from the multicentre COIN-B trial

Abstract

Background and aims: Determinants of outcomes after nucleos(t) ide analogue (NUC) cessation remain incompletely defined. Ethnicity has been proposed as a stopping criterium, but prospective validation is lacking. We evaluated the impact of ethnicity and HBV genotype (gt) on off-treatment outcomes. Method: In the multicentre prospective COIN-B trial, start-of-treatment HBeAg-, long-term NUC-suppressed patients without advanced liver fibrosis were followed for 72 weeks after NUC cessation. Recruitment was matched for Caucasian and non-Caucasian ethnicity and stratified by sex and age. The primary endpoint was off-treatment HBV DNA ≤2000 IU/mL + ALT ≤2×ULN at week 72. Ethnicity was defined by country of birth. Ancestry inference was determined using population-specific SNPs. Results: Of 91 included patients, 84 completed follow-up (Caucasian: n = 41; non-Caucasian: n = 43). Both groups had comparable end-of-treatment (EOT) quantitative HBsAg levels (p = 1.00). Caucasians were exclusively infected with gt A or gt D, whereas non-Caucasians