A5300B/IMPAACT 2003B - Protecting Households On Exposure to Newly Diagnosed Index Multidrug-Resistant Tuberculosis Patients (PHOENIx MDR TB) - is a Phase III, open label, multi-center trial with a cluster- randomized superiority design (eligible contacts in the same household are a cluster), to compare the efficacy and safety of 26 weeks of delamanid versus 26 weeks of isoniazid for preventing confirmed or probable active TB during 96 weeks of follow-up among high-risk household contacts of multidrug-resistant tuberculosis (MDR) TB patients. It is expected that more than 3,400 high-risk contacts from about 1,700 households (assuming two eligible contacts per household) will be enrolled. This study is a collaborative effort between the IMPAACT and ACTG networks.
The investigation will begin with a pilot study (A5300/IMPAACT 2003) to demonstrate the feasibility of the main trial and to inform its operational plans. The pilot phase is a cross-sectional study of adult MDR TB index cases and their household contact(s). Up to 300 adult MDR TB index cases and the eligible contacts in their household will be enrolled. The study objectives are to describe the feasibility of identifying, recruiting, and characterizing adult MDR TB index cases and their adult and child household contacts for enrollment into the main PHOENIx trial and to describe the prevalence of latent TB infection, TB disease, and HIV infection among adult and child household contacts.