Comparisons were made of the in vitro activity of rifampicin, and the rifamycin derivatives, rifapentine, rifabutin, CGP 29861, CGP 7040 and CGP 27557, against rifampicin-sensitive and rifampicin-resistant strains of Mycobacterium tuberculosis and against the Mycobacterium avium/intracellulare/scrofulaceum (MAIS) complex. The new rifamycins had MICs four to eight times lower than those of rifampicin against sensitive M. tuberculosis strains. Of the 35 rifampicin-resistant strains of M. tuberculosis 31% were sensitive to rifabutin but only 3-11% to the other rifamycins. The proportions of the MAIS strains found to be sensitive were 35% for rifapentine and rifabutin and 85-92% for CGP 29861 and CGP 7040. © 1987.
Dickinson, J. M., & Mitchison, D. A. (1987). In vitro activity of new rifamycins aganst rifampicin-resistant M. tuberculosis and MAIS-complex mycobacteria. Tubercle, 68(3), 177–182. https://doi.org/10.1016/0041-3879(87)90053-5