This is a multi-centre study conducted in 120 participants. All treatment groups will receive ChAdOx1-HBV on Day 1 and MVA-HBV on Day 29, and MVA boosts and nivolumab infusions as per treatment group as follows: Group 1: ChAdOx1-HBV, MVA-HBV and low dose nivolumab. Group 2: ChAdOx1-HBV, MVA HBV + low dose nivolumab, MVA HBV and low dose nivolumab. Group 3: ChAdOx1-HBV, MVA HBV, low dose nivolumab , MVA HBV. All participants return 7 days after each treatment (both immunotherapeutic and nivolumab infusion) visit to have chemistry and haematology safety laboratory studies obtained.~Participants are randomised to treatment in a 1:1:1 allocation. The primary objective of the study is to assess the efficacy of VTP-300 in combination with low-dose nivolumab in well-controlled CHB infection. The secondary objective of the study is to determine the safety and reactogenicity of the treatment regimens; this will be assessed by analysis of the incidence and severity of (serious) adverse events and any changes in laboratory values and vital signs. To assess the effect of VTP-300 in combination with low-dose nivolumab on the clearance of HBsAg and the impact of multiple booster doses of MVA-HBV and assess the appropriate timing of the use of low-dose nivolumab when used in combination with VTP-300.~Participants remain in the study for 12 months and attend clinic visits for treatment and assessments on Days 1, 8, 29, 36, 57, 85, 92, 113, 169, 252 and 336 (per Group allocation).
This is an open-label study to determine the efficacy, safety, tolerability and immunogenicity of ChAdOx1-HBV and MVA-HBV, together VTP-300, in combination with low-dose nivolumab, in patients with chronic HBV who are virally suppressed with oral anti-viral therapies.