This study will evaluate the effect of adding metronidazole to standard second-line therapy for tuberculosis in patients who have multi-drug resistant tuberculosis (MDR-TB) of the lungs. It will evaluate the safety and tolerability of metronidazole in combination with antituberculosis agents. Metronidazole is a drug widely used to treat bacterial and parasitic infections occurring in environments with very little oxygen such as the human colon. Nine million new cases of sputum-positive tuberculosis are diagnosed worldwide each year.
Patients ages 20 and older who have symptoms of TB, who have been treated for tuberculosis but whose disease is multi-drug resistant, and who are not pregnant or breast feeding may be eligible for this study. They will be recruited in the National Masan Tuberculosis Hospital (NMTH), Masan, Republic of Korea. Patients will undergo the following tests and procedures:
- Collection of sputum for counting of bacteria.
- Drawing of blood for routine blood chemistry analysis; for measuring levels of metronidazole; TB lipid analysis; and for testing levels of T-cells, which are part of an immune response.
- Two targeted positron emission tomography (PET) scans, each with a computed tomography (CT) scan, and five high-resolution CT scans.
Patients will receive either an 8-week course of standard second-line agents plus placebo (sugar pill) or an 8-week course of standard agents plus metronidazole. The subjects, doctors and researchers will not know which patients are taking the metronidazole until after the first 2 years of the trial. A total of 60 patients will be assigned to two cohorts of 30 patients each. After 8 weeks, all patients will return to the standard of care chemotherapy, according to normal procedures at NMTH.
Side effects of metronidazole commonly reported are vaginal discharge, symptoms of Candida cervicitis and vaginitis, headache, nausea and vomiting, and dizziness. Peripheral neuropathy, an abnormal condition of the nerves, may also be a side effect. The precise incidence of neuropathy is unknown but is usually related to the duration of metronidazole use. It can almost always be reversed when the drug is discontinued. Serious side effects, though rare, may include leukopenia and thrombocytopenia (disorders in the blood), seizures and other central nervous system problems, and hepatitis.
This study may or may not have a direct benefit for participants. However, it is possible that patients' drug-resistant disease may be more effectively treated as a result of metronidazole. The study may help identify new methods for measuring drug effectiveness during TB studies.