TB Nutrition, Immunology and Epidemiology

This double blinded, randomized, placebo controlled trial will enroll 600 men and women, who are age 18 to 65 years inclusive, have at least two positive sputum smears for tuberculosis (TB), intend to stay in Dar-es-Salaam (DSM) for at least 2 years from the start of TB therapy, and have given informed consent to participate in the study. Half of the enrollees will have active TB and co-infection with HIV, and the other half will have TB alone. The effect of micronutrient status will be examined in the context of a randomized trial conducted in Tanzania. Subjects will be randomized to receive either multi-micronutrients or placebo from the start of their TB therapy, through the 8 months of anti-TB therapy, and until the last recruited patient reaches 24 months of follow up. Thus, the first subject is likely to be followed for 48 months, assuming the duration of recruitment is 24 months. The endpoints of interest include bacteriologic cure, immune response parameters, and clinical outcomes. The researchers will also examine the utility of these immune response parameters as surrogate markers for treatment efficacy in TB, irrespective of nutritional and other risk factors. The study will be carried out as a collaborative effort between Harvard School of Public Health; Muhimbili University College of Health Sciences, Dar es Salaam, Tanzania; Tufts University, Boston; and the Channing Laboratory, Boston. Subjects will be randomly assigned to receive a daily oral dose of one of two treatments: (a) micronutrients: 5000 IU of retinol, 20 mg of B1, 20 mg of B2, 25 mg of B6, 100 mg of niacin, 50 mcg of B12, 500 of C, 200 mg of E, 0.8 mg of folic acid, and 100 mcg of selenium; or (b) placebo. The primary objectives are to: (1) determine the efficacy of micronutrient supplements on sputum and culture negativity at one month and two months; (2) determine the efficacy of micronutrient supplements on survival between two arms at 8 and 24 months; and (3) determine the efficacy of micronutrient supplements on TB relapse and reinfection. Secondary study objectives are to: (1) compare the treatment arms with respect to rate of change of HIV viral load in HIV positive subjects measured at 0, 2, 8, and 20 months; (2) compare the treatment arms with respect to absolute change in CD4 counts from 0 to 2, 8, 20 months; (3) compare the treatment arms with respect to weight change from baseline and 2 months, 8 months, and 20 months; (4) compare the treatment arms with respect to immunological parameters, namely ex vivo lymphocyte proliferation; and cytokine production, namely IL-2, INF-g, IL-12, and TNF-a, at 2, 8, 20 months; and (5) correlate the above mentioned immunological markers with smear conversion rates at 1 month, 2 months, cure, relapse, and death.