A Mechanistic Study of GSK3228836 With Fine Needle Aspiration (FNA) in Participants With Chronic Hepatitis B

Hepatitis B virus (HBV) infection, especially chronic, is a significant worldwide medical problem. This is an exploratory study of the therapeutic mechanism of GSK3228836 in participants with chronic hepatitis B (CHB) on stable nucleos(t)ide therapy (which is the first line therapy for CHB). This study is a Phase IIa, multi-center open label exploratory study of the therapeutic mechanism of GSK3228836 in participants with hepatitis B virus e-antigen (HBeAg)-negative CHB on stable nucleos(t)ide therapy using repeat fine needle aspirations of the liver for intrahepatic immunophenotyping. It will investigate the virologic and immunologic correlates of hepatitis B virus surface antigen (HBsAg) loss observed in participants when treated for 12 weeks with 300 milligrams (mg) GSK3228836. Repeat fine needle aspirates of the liver will be performed to enable analysis of liver-resident immune cells to investigate any immunomodulatory properties of GSK3228836 and to study the biology of underlying treatment-associated liver flares. The study will consist of a screening, treatment, and post-treatment follow-up phase. Approximately 20 participants will be enrolled in the study.