Sputum Pharmacokinetics of TB Drugs and Bacterial Drug Resistance
Sputum Pharmacokinetics of TB Drugs and Bacterial Drug Resistance
Background:

 Many people around the world get tuberculosis (TB) and non-tuberculous mycobacteria (NTM)
 infections. Sometimes medicine that treats these infections does not get to where the
 bacteria are in the lungs. Researchers want to find a way to tell if enough medicine is
 getting to where it is needed in the lungs. They will look at how much medicine is in your
 sputum (what you cough up) compared to how much is in your blood. They will also investigate
 a new test to quickly figure out what medicines are likely to treat TB effectively.

 Objective:

 To determine the relationship between the concentration of TB drugs in plasma and sputum over
 time.

 Eligibility:

 People ages 18 and older who have TB or NTM infection that is suspected to be drug resistant.
 They must be taking TB or NTM medicines.

 Design:

 Participants will be screened with medical history.

 Participants will be in the study for 2 8 days.

 Participants will give 3 or more sputum samples over at least 2 different days. They will
 cough sputum into a cup.

 Participants will have blood drawn 4 times a day on 2 different days.
This study will support two avenues of research, pharmacokinetics (PK) of drugs used to treat
 tuberculosis and resistance to those drugs that has been developed by the pathogen. Given the
 high inter-individual variability in TB drug exposure, therapeutic drug monitoring would be
 of value to adjust the drug dose in TB patients in order to improve clinical outcome and
 minimize toxicity. It is not practiced in most settings for reasons associated with costs but
 also because blood collection is an invasive procedure. Sputum on the other hand is often
 produced spontaneously and discarded as waste. Drug levels can be measured in sputum just as
 in plasma. Here we will test the hypothesis that sputum drug levels are predictive of drug
 concentrations in plasma and/or in specific lesion compartments such as the caseum of open
 cavities. We will also characterize the exposure of standard 1st and 2nd line TB drugs at one
 of the sites of infection, since sputum is in direct contact with cavity caseum. The subjects
 will contribute three or more sputum samples spontaneously produced over at least two days
 and four blood samples following drug administration on two different days (8 blood samples
 total). The data will be analyzed using population PK modeling approaches to generate
 concentration-time profiles and 24-hour area under the curve (AUC) of each study drug in
 sputum. Correlations between these values, plasma and lesion AUCs will be examined. We will
 draw from a recently completed TB lesion pharmacokinetic study (www.ClinicalTrials.gov
 #NCT00816426) to seek correlations between drug exposure in sputum and in pulmonary lesions.
 In addition to drug concentrations, sputum will be cultured by standard methods to isolate
 Mycobacterium tuberculosis (Mtb), determine the drug resistance profile, and be saved for
 testing a second generation of the Xpert TB XDR assay.
-  INCLUSION CRITERIA:

 1. At least 18 years of age

 2. Diagnosis of TB (and/or NTM for NIH clinical center subjects)

 3. Ongoing signs and/or symptoms of pulmonary TB (and/or NTM at the NIH CC)

 4. Suspected drug resistance (drug susceptible allowed at the NIH CC)

 5. Available to provide at least 3 sputa over 2 or more days

 6. Taking anti-tuberculosis medicines (or NTM meds at NIH CC) during the time sputa
 are provided

 7. Thought likely to be Mycobacterium culture positive (including NTM infected for
 the NIH CC) by enrolling physician

 8. GeneXpert MTB/RIF sputum TBpositive (China subjects only)

 9. Likely able to produce sputum samples while on study

 10. Willing to provide blood samples

 11. Willing to have samples stored

 EXCLUSION CRITERIA:

 1. Acute liver or kidney disease

 2. Conditions which compromise the subject s ability to take or absorb oral drugs