A Dose-Finding Study to Guide Use of Verapamil as an Adjunctive Therapy in Tuberculosis.
Clin Pharmacol Ther
; 115(2): 324-332, 2024 02.
Article
en En
| MEDLINE
| ID: mdl-37983978
ABSTRACT
Induction of mycobacterial efflux pumps is a cause of Mycobacterium tuberculosis (Mtb) drug tolerance, a barrier to shortening antitubercular treatment. Verapamil inhibits Mtb efflux pumps that mediate tolerance to rifampin, a cornerstone of tuberculosis (TB) treatment. Verapamil's mycobacterial efflux pump inhibition also limits Mtb growth in macrophages in the absence of antibiotic treatment. These findings suggest that verapamil could be used as an adjunctive therapy for TB treatment shortening. However, verapamil is rapidly and substantially metabolized when co-administered with rifampin. We determined in a dose-escalation clinical trial of persons with pulmonary TB that rifampin-induced clearance of verapamil can be countered without toxicity by the administration of larger than usual doses of verapamil. An oral dosage of 360 mg sustained-release (SR) verapamil given every 12 hours concomitantly with rifampin achieved median verapamil exposures of 903.1 ng.h/mL (area under the curve (AUC)0-12 h ) in the 18 participants receiving this highest studied verapamil dose; these AUC findings are similar to those in persons receiving daily doses of 240 mg verapamil SR but not rifampin. Moreover, norverapamilverapamil, RS verapamil, and RS norverapamil AUC ratios were all significantly greater than those of historical controls receiving SR verapamil in the absence of rifampin. Thus, rifampin administration favors the less-cardioactive verapamil metabolites and enantiomers that retain similar Mtb efflux inhibitory activity to verapamil, increasing overall benefit. Finally, rifampin exposures were 50% greater after verapamil administration, which may also be advantageous. Our findings suggest that a higher dosage of verapamil can be safely used as adjunctive treatment in rifampin-containing treatment regimens.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Contexto en salud:
2_ODS3
/
3_ND
Problema de salud:
2_enfermedades_transmissibles
/
3_neglected_diseases
/
3_tuberculosis
Asunto principal:
Tuberculosis
/
Mycobacterium tuberculosis
Límite:
Humans
Idioma:
En
Revista:
Clin Pharmacol Ther
Año:
2024
Tipo del documento:
Article
País de afiliación:
India