The cumulative incidence of severe alanine aminotransferase (ALT) flares was low and associated with greater decreases in HBV DNA and loss of HBeAg, but not with loss of HBsAg, in a racially heterogeneous cohort of adults with chronic hepatitis B virus (HBV) infection. Researchers collected clinical and laboratory data from 1,587 participants in the Hepatitis B Research Network at enrollment, at weeks 12 and 24, and every 24 weeks thereafter for a planned 5 years of follow-up from January 2011 through May 2016. They found:

• ALT flares occurred in 102 (6%) participants, with 31 (30%) flares occurring at baseline.
• The 4-year cumulative incidence of ALT flares was 5.7%.
• Male sex and higher baseline HBV DNA values were associated with occurrence of an ALT flare; older age was associated with lower odds of an ALT flare.
• Rate of decrease in level on HBV DNA by ≥ 1 log10 and HBeAg loss were higher in patients with an ALT flare vs those without, but the rate of HBsAG loss was similar.