AB-729 is in injected RNAi agent that targets HBsAg.
Not much has changed since the previous update on this phase-1 trial in late 2020 (#msg-159504853). Despite the inclusion of two new dosing cohorts (60mg q8w and 90mg q4w), HBsAg reduction is middling (1.6-1.8 logs at 24w — see slide #9 in the second link above), and it is essentially the same for all three dosing cohorts, which is not a great sign.