New vaccines for the prevention of tuberculosis in human immunodeficiency virus infection [Perspectives]

The prevention of human immunodeficiency virus (HIV) associated tuberculosis (TB) remains challenging. Several vaccines against TB have advanced to clinical trials in patients with HIV infection. The DarDar Trial, a large, randomized, placebo-controlled efficacy trial conducted in Tanzania, has demonstrated that a multiple dose series of an inactivated whole cell mycobacterial vaccine is safe in HIV and can prevent HIV-associated TB in patients with childhood bacille Calmette-Guérin vaccination and CD4 counts of ≥200 cells/mm³. These developments offer promise that in the not too distant future immunization with an effective vaccine against TB can be added to other strategies for the prevention of HIV-associated TB. This expanded approach is referred to as the Five ‘I's’: intensified case finding, infection control, isoniazid preventive therapy (IPT), initiation of antiretroviral therapy (ART), and immunization against TB. We encourage additional studies of new TB vaccines in HIV, and propose a strategy to reduce the risk of TB by integrating IPT, ART and immunization into routine HIV care. At the time of HIV diagnosis, patients with CD4 counts of ≥200 cells/mm³ could receive immunization, IPT and, as appropriate, ART. In patients presenting with lower CD4 counts or already on ART, immunization could be initiated at CD4 counts of ≥200 cells/mm³ to add to the protection afforded by IPT and ART.