Activity of drug combinations against dormant Mycobacterium tuberculosis.

Aerobic (5-day-old cultures) and nonreplicating (dormant) Mycobacterium tuberculosis (5-, 12-, and 19-day-old cultures) bacteria were treated with rifampin (R), moxifloxacin (MX), metronidazole (MZ), amikacin (AK), or capreomycin (CP) for 7, 14, and 21 days. R-MX-MZ-AK and R-MX-MZ-CP killed both aerobic and dormant bacilli in 21 days, as shown by lack of regrowth in solid and liquid media. R-MX-MZ-AK and R-MX-MZ-CP also caused a strong decrease of nonreplicating bacilli in 7 days in a cell-based dormancy model.