A trial of isoniazid preventive therapy (IPT) plus antiretroviral therapy (ART) to prevent TB has shown safety and efficacy in patients with HIV, according to a UCT research team, whose findings were published in The Lancet in 2014. TB is the biggest cause of morbidity and mortality in people infected with HIV in Africa. Both IPT and ART protect against TB in HIV-infected people, but it was not known if the two would give additional protection or could be safely combined.
The research team was headed up by Dr Molebogeng Rangaka and included clinic staff working for Médecins Sans Frontières (MSF) and the Western Cape Provincial Government, with supervision from Professor Gary Maartens and Professor Robert Wilkinson from the Department of Medicine. They conducted a trial of IPT in people on ART to prevent TB at Khayelitsha Site B Clinic in Cape Town. The addition of IPT was found to be safe and to reduce TB incidence by 37%.
Discussing the purpose of the study, Professor Maartens explains that it is well established that the risk of TB can also be reduced by IPT in HIV-infected people not on ART. However, ART also reduces the risk of TB. It was previously unknown whether isoniazid would give additional benefit and whether it was safe in patients on ART.
“These findings will change clinical practice and contribute immensely to the reduction of the scourge of TB. It is one of the highlights of research in the faculty in recent times,” says Professor Bongani Mayosi, head of medicine.
The study was funded by the Department of Health, MSF, the Wellcome Trust and the European and Developing Countries Clinical Trials Partnership, while MSF were key partners in conducting the study.