Efficacy of Oral Zinc Administration as an Adjunct Therapy in New Pulmonary Tuberculosis (Category I) Patients

Overview

The primary objective of the study is to evaluate the efficacy of oral Zinc administration in new smear positive pulmonary tuberculosis patients. Evidence is available suggesting that zinc deficiency rapidly diminishes antibody- and cell-mediated immune responses in both humans and animals and renders the individual susceptible to a variety of pathogens. This micronutrient has also been found to be useful in the treatment of lung tuberculosis in limited number of patients. We are conducting this study in category-I patients (As per World Health Organization, Geneva classification of tuberculosis) having lung tuberculosis to see the efficacy and also to see any change in the immunological parameters.

Malnutrition is commonly observed in patients with pulmonary tuberculosis. There are reports claiming patients with active pulmonary tuberculosis are malnourished as indicated by diminished visceral proteins, anthropometric indexes, and micronutrient status. Zinc plays role in protecting cells from the damaging effects of free radicals. Zinc supplementation was shown to prevent pulmonary pathology due to hypoxia-induced lung damage in rats. The role of zinc in faster sputum smear conversion has not yet been studied. However, there are reports which confirms, in vitro cellular killing of tubercle bacilli by macrophages after zinc supplementation. We are investigating oral zinc supplement for its efficacy in TB patients in a "double-blind placebo-controlled randomized clinical trial" fashion. We are conducting this trial in Category-I pulmonary TB Patients (as per RNTCP, Ministry of Health and Family Welfare, Govt.of India), and are assessing the outcome in the form of clinical improvement, sputum conversion and immunological parameters. This is a multi-centric trial sponsored by the Department of Biotechnology, Ministry of Science and Technology, Govt. of India. Supplements and placebo have been prepared by Cadila pharmaceutical Ltd., India, in the form of tablets. Each micronutrient tablet contains 50mg zinc (as zinc sulphate) in a lactose matrix. The placebo consisted of lactose alone. Supplement and placebo capsules were indistinguishable in appearance both externally and internally. In this clinical trial one tablet of zinc as oral supplement will be given everyday during the entire course in line with the directly observed treatment, short-course (DOTS) strategy recommended by the World Health Organization.