PK of Levofloxacin in MDR-TB Patients

The emergence and spread of multi-drug resistant and extensively-drug resistant strains of Mycobacterium tuberculosis (MDR/XDR-TB) have posed a great threat to global TB control and elimination, limiting treatment success rate at worrisome 50% for MDR-TB. Among various factors contributing to the development of drug resistance, low drug exposure is well recognized. To overcome this, either new drugs have to be developed or the dose of currently used therapy be optimized, or both. Fluoroquinolones (levofloxacin and moxifloxacin) and aminoglycosides are important drugs in the MDR-TB treatment regimen. Development of acquired drug resistance to these drugs could complicate and narrow down the available options, and further exacerbate to pre-XDR and XDR-TB.

Objective:

The main objective of this prospective clinical study is to understand the pharmacokinetics of levofloxacin in MDR-TB patients, receiving standard dosage (750-1250mg) based on the body weight and correlate drug exposure, with treatment outcomes.

Study design:

A prospective pharmacokinetic study

Study population: 20 MDR-TB patients

Intervention: Patients receive once daily oral dosing of levofloxacin (750-1250mg) based on the body weight, under MDR-TB treatment regimen of Nepal.

Main study parameters/end points:

The pharmacokinetic parameters(Vd, CL, AUC etc.) of levofloxacin are the primary end points of the study. The Cmax/MIC and AUC0-24h/MIC ratios are the best predictive parameters for efficacy of levofloxacin treatment and will be estimated. Pharmacokinetics will be evaluated in plasma and in oral fluid