Previous Article | Next Article ![]()
Antimicrobial Agents and Chemotherapy, August 1999, p. 1870-1874, Vol. 43, No. 8
Kuzell Institute for Arthritis and Infectious
Diseases,
Received 16 February 1999/Returned for modification 23 April
1999/Accepted 11 May 1999
Despite the development of several agents, new classes of
antimicrobials with activity against the Mycobacterium
avium complex (MAC) are needed. Based on a broad screening of
compounds, we found that mefloquine has MICs of 8 to 16 µg/ml by the
BACTEC system and 16 µg/ml by broth microdilution for five MAC
strains tested. An expansion of the screening with broth microdilution to 24 macrolide-susceptible strains and 6 macrolide-resistant strains
determined that the MIC for all strains was 16 µg/ml. To determine
the intracellular activity of mefloquine, U937 macrophage monolayers
infected with MAC strain 101, 100, or 109 (serovars 1, 8, and 4) were
treated with mefloquine daily, and the number of intracellular bacteria
was quantitated after 4 days. Significant growth inhibition against the
three MAC strains at concentrations greater than or equal to 10 µg/ml
(P < 0.05) was obtained. Due to the encouraging
anti-MAC activity, in vivo efficacy in beige mice infected with MAC 101 was evaluated. Animals were treated with 5, 10, 20, or 40 mg/kg of body
weight daily, three times a week, twice a week, or once a week for 4 weeks, and bacteria were quantitated in blood, liver, and spleen. No
toxicity was observed with any of the treatment regimens. Mefloquine
had borderline bactericidal activity at a dosage of 40 mg/kg daily
(100% inhibition compared with a 1-week control), and significant
inhibition was obtained at dosages of 40 mg/kg three times a week, as
well as 20 mg/kg daily. Mefloquine had no significant effect on
bacteremia. A combination of mefloquine and ethambutol showed
significantly more activity than did either drug alone in liver,
spleen, and blood; the combination was also bactericidal against
M. avium. Although safety is a potential concern,
mefloquine and related compounds deserve further investigation as
anti-MAC therapies.
0066-4804/99/$04.00+0
Copyright © 1999, American Society for Microbiology. All rights reserved.
Mefloquine Is Active In Vitro and In Vivo against
Mycobacterium avium Complex
*
Corresponding author. Mailing address: Kuzell
Institute, 2200 Webster St., Suite 305, San Francisco, CA 94115. Phone:
(415) 561-1734. Fax: (415) 441-8548. E-mail: luizb{at}cooper.cpmc.org.
Antimicrobial Agents and Chemotherapy, August 1999, p. 1870-1874, Vol. 43, No. 8
0066-4804/99/$04.00+0
Copyright © 1999, American Society for Microbiology. All rights reserved.
This article has been cited by other articles:
Copyright © 2009 by the American Society for Microbiology. For an alternate route to Journals.ASM.org, visit: http://intl-journals.asm.org | More Info»