Protektem pikinini blong yu trial: protocol for a single arm field trial to assess the effectiveness of treating-all pregnant women with hepatitis B infection with tenofovir prophylaxis to prevent mother-to-child transmission in Vanuatu, 2024-2025.

BACKGROUND

Hepatitis B infection is a major public health concern in Vanuatu, with approximately 9% of the general population estimated to be living with chronic hepatitis B. Most new infections are due to mother-to-child transmission (MTCT). Hepatitis B vaccination is available in Vanuatu, but coverage rates for first dose within 24 h of birth and third dose are suboptimal. While treatment of chronic hepatitis B infection with tenofovir disoproxil fumarate (TDF) is available in country, there is no capacity to test hepatitis B e antigen and limited capacity to test hepatitis B virus (HBV) DNA viral load, which is a current eligibility requirement for women in pregnancy to access hepatitis B prophylaxis for MTCT per National guidelines. Recently, the World Health Organization guidelines have been updated to recommend universal peripartum antiviral prophylaxis (PAP) of pregnant women living with hepatitis B to prevent MTCT of HBV, without assessment of viral load in places without access to testing. However, these recommendations are conditional based on low-certainty evidence. The aim of this trial is to evaluate the effectiveness and safety of universal PAP and provide evidence for the global guidelines.

METHODS

A single arm field trial compared to real world control sites will be conducted in Vanuatu involving pregnant women attending antenatal care services with positive HBsAg rapid tests. Participants at the control sites will undergo routine care. Participants at the intervention sites will all receive oral TDF prophylaxis from second trimester to completion of infant primary hepatitis B vaccination schedule. Primary data analysis will be by intention-to-treat. Initial analyses will be unadjusted comparisons of the intervention sites and control sites. Adjusted analyses will be performed, as needed, and presented in addition to unadjusted comparisons.

DISCUSSION

This study will provide evidence of acceptability, effectiveness and cost-effectiveness of prophylaxis for all women with hepatitis B during pregnancy, as per the updated WHO guidelines, compared with current practice. The outcome of this trial will provide critical information to inform national and global guidelines around universal peripartum antiviral prophylaxis for hepatitis B during pregnancy.

TRIAL REGISTRATION

Australian New Zealand Clinical Trials Registry (ANZCTR), ACTRN: ACTRN12623001202651p. Registered 21 November 2023.