For more than a decade, the CHAPAS Consortium have conducted a series of clinical trials that have helped to shape international policy and practice on antiretroviral use in HIV-infected children. Data from EDCTP-funded CHAPAS 1 and CHAPAS 3 projects supported licensing applications for children-specific formulations and provided evidence in support of WHO recommendations on updated treatment options, opening the door to more extensive use of antiretroviral therapy in African children.

The ongoing CHAPAS 4 study is designed to identify an optimal second-line treatment for children with HIV infections. The study, being carried out in three sub-Saharan countries, will use an innovative trial design to compare a range of possible options. These include formulations incorporating dolutegravir, a relatively new drug with significant advantages over existing treatments; atazanavir/ritonavir (ATV/r), which is now available in a single pill suitable for children; and tenofovir–alafenamide (TAF), a tenofovir pro-drug that may be particularly suitable for use in children, co-formulated with emtricitabine. These agents will be tested in different combination regimens against the current standard of care for children.

The project will also explore interactions between antiretroviral drugs and anti-TB medications, and their impact on the effectiveness of treatment and toxicity. It will also examine the cost implications of the new treatments.