This study will compare the efficacy and safety of 26 weeks of delamanid (DLM) versus 26 weeks of isoniazid (INH) for preventing confirmed or probable active tuberculosis (TB) during 96 weeks of follow-up among high-risk household contacts (HHCs) of adults with multidrug-resistant tuberculosis (MDR-TB) (index cases). High-risk HHCs are those with HIV or non-HIV immunosuppression, latent TB infection, and young children below the age of 5 years.

If at least one HHC within a household (HH) is found to be eligible, the HH will be randomized to one of the following:

Arm A: DLM daily for adults, adolescents, and children, given for 26 weeks.

Arm B: INH daily for adults, adolescents, and children, given for 26 weeks AND pyridoxine (vitamin B6) daily for adults, adolescents, and children, given for 26 weeks.

All high-risk HHCs in the same HH will receive the same randomized regimen.

All participants will be in the study for 96 weeks. At study entry, index cases will undergo a medical history review and sputum collection. HHCs will have study visits at study entry and at Weeks 2, 4, 8, 12, 16, 20, 26, 36, 48, 60, 72, 84, and 96. Visits may include physical examinations; blood, urine, and sputum collection; electrocardiograms (ECGs); and questionnaires and assessments. Forty HHCs under the age of 5 taking DLM will undergo an intensive PK visit at Week 8.

Men and women age greater than or equal to 18 year

Start date: 8/19/2019