“
crucial in

widening African

children’s access

to antiretrovirals

”

Bringing antiretroviral drugs to children

The CHAPAS trials have ensured that many more children with HIV have benefited
from life-saving antiretrovirals.

The challenge

HIV is a highly diverse and rapidly evolving pathogen. Despite much effort, a vaccine that would protect against multiple HIV variants has yet to be developed, threatening global efforts to bring the HIV/AIDS epidemic under control by 2030.

However, a small number of individuals worldwide have been found to produce ‘broadly neutralising antibodies’ – antibodies that recognise structures common across many HIV strains. There are hopes that these antibodies could be mass produced and used in passive immunisation – given to people periodically to protect against infection.

The CAP012 SAMBA project builds on the discovery of a broadly neutralising antibody, known as CAP2456-VRC26.25, in a woman from KwaZulu Natal. Excitingly, this antibody, and two others, have been found to protect monkeys from infection with the monkey version of HIV.

The CAP012 SAMBA project is extending this work by analysing the safety of the antibodies in people, exploring their acceptability to potential recipients, and monitoring their metabolism in the body. On the basis of these studies, the most promising combinations of antibodies will be taken forward to a phase II trial to assess safety and efficacy at preventing HIV infection.

The project

The later CHAPAS-3 trial compared the efficacy and safety of three fixed-dose combinations including two without stavudine (found to have some long-term side effects in adults, leading to a recommendation that its use be discontinued in children). The trial the first of its kind in Africa studied nearly 500 children at four sites in two African countries.

The CAP012 SAMBA project could advance the development of a radically new approach to HIV prevention. It offers the prospect of HIV protection delivered through injections every four to six months. Notably, it is envisaged as an approach of particular benefit to women – the antibodies are being evaluated in groups of women, and the intervention is one that places HIV control in the hands of women, who are currently experiencing the brunt of the HIV epidemic in Africa.

ratios forfixed-dose combinations and on appropriatedosage according to weight. 

The CHAPAS-3 trial confirmed the effectiveness of fixed-dose combinations, providing further impetus to the rollout of antiretrovirals to children. Its evidence on abacavir informed the WHO recommendation of abacavir-containing combinations for first-line therapy in children. Trial data have also been used to support applications for regulatory approval for new scored efavirenz tablets.

Impact