HIPOCAMP (ANRS 0562s)

Mother-to-child transmission of the hepatitis B virus remains a major public health problem in low-resource countries. The World Health Organization recommends measuring the amount of virus in the blood of every pregnant woman living with HBV, to identify those at risk of passing the virus on to their baby who need preventive treatment (tenofovir).

However, this test remains hard to access in many regions, especially in rural areas. WHO proposes a simpler alternative: treating all women living with HBV, without knowing their viral load. This strategy simplifies care, but means treating many women who would not need it.

HIPOCAMP is a RIPH 2 study being conducted in 4 countries: Vietnam, Cameroon, Côte d’Ivoire, Togo.

It compares two prevention strategies during pregnancy:

• Strategy 1: systematically treating all women living with the virus with tenofovir.
• Strategy 2: targeting treatment using a new rapid test that can be performed on site (point-of-care), without a laboratory

The study will measure whether women take their treatment, remain in care and whether the amount of virus decreases by delivery. An additional component looks at women’s experiences and at the acceptability of each approach. 3,200 women living with HBV will be enrolled and followed up until 9 months after delivery.

Objectives of the HIPOCAMP project

Primary objective

To assess whether a targeted strategy using the innovative high-sensitivity HBeAg rapid diagnostic test in HBV-infected pregnant women at decentralised sites is non-inferior to a universal strategy, in which all HBV-infected women receive tenofovir (TDF) prophylaxis, in terms of retention in care and reduction of HBV DNA levels at delivery.

Secondary objectives

1. To estimate the risk of HBV infection in children at nine months in each strategy.
2. To assess the cost and cost-effectiveness of both strategies.
3. To compare the acceptability, appropriateness and feasibility of the strategies.
4. To assess all serious adverse events and adverse events of special interest occurring in women and children taking part in the study.
5. To assess postpartum linkage to care and identify barriers and facilitators.
6. To assess women’s knowledge of HBV and their health literacy.
7. To explore women’s disclosure of their HBV status to their partners and children, as well as their perceptions and experiences of testing their partners and children.

Enrolment

The first enrolment took place on 10 August 2026 in Vietnam. Two countries are open to enrolment: Vietnam and Côte d’Ivoire.