Improving Treatment of Nontuberculous Mycobacterial Infection in Cystic Fibrosis
- Conditions
- Cystic Fibrosis
- Interventions
- Registration Number
- NCT02372383
- Lead Sponsor
- University of Colorado, Denver
- Brief Summary
The purpose of this study is to determine antimycobacterial drug pharmacokinetics (PK) and pharmacodynamics (PD) in patients with cystic fibrosis (CF) to improve treatment of nontuberculous mycobacterial (NTM) lung disease.
- Detailed Description
The purpose of this study is to determine antimycobacterial drug pharmacokinetics (PK) and pharmacodynamics (PD) in patients with cystic fibrosis (CF) to improve treatment of nontuberculous mycobacterial (NTM) lung disease.
Aim 1: Determine the PK profile of oral antimycobacterial drugs (azithromycin, rifampin and ethambutol) under both fasting conditions and when taken with food plus supplemental pancreatic enzymes in subjects with pancreatic insufficient, compared to healthy controls.
Aim 2: Begin to investigate the influence of inflammation, host characteristics, and drug metabolism on the PK of the antimycobacterial drugs.
Aim 3: Estimate an optimized dosing regimen for the antimycobacterial drugs against Mycobacterium avium complex (MAC) using historic minimum inhibitory concentration (MIC) data and models of Mycobacterium tuberculosis or MAC infection.
The central goal of this study is to improve treatment of NTM infection in CF. Upon completion of this study the investigators will determine if and why PK of the antimycobacterial drugs are altered in CF. More importantly, the investigators will develop CF-specific guidelines to achieve therapeutic goals with recommendations for drug dosing (including dose, dose frequency and timing in relation to meals and supplemental pancreatic enzymes) and timing of therapeutic monitoring to be used for future treatment of NTM lung disease in CF.
Recruitment & Eligibility
- Status
- COMPLETED
- Sex
- All
- Target Recruitment
- 31
- CF diagnosis defined as a sweat chloride >60mEq/L and/or the presence of two disease-causing CFTR mutations.
- Ages 16 years and above.
- Pancreatic insufficient status defined as previous fecal pancreatic elastase <100mcg/g stool and/or having 2 disease-causing CFTR mutations known to be associated with pancreatic insufficiency, and taking supplemental pancreatic enzymes between 1000-2500 lipase units/kg/meal.
- No positive NTM cultures in the last 2 years.
- Pulmonary function: Most recent FEV1 > 40% predicted.
- Willing to participate in and comply with the study procedures, and willingness of a parent or legally authorized representative to provide written informed consent for those subjects less than 18 years of age.
Healthy Control Inclusion Criteria:
- Ages 18 years and above.
- BMI below 30 to best match CF body type.
- Willing to participate in and comply with the study procedures, and willingness of a parent or legally authorized representative to provide written informed consent for those subjects less than 18 years of age.
CF Subject
- Allergy or intolerance to rifampin, ethambutol, or azithromycin.
- Hepatic insufficiency defined as having an AST or ALT greater than three times the upper limit of normal at the screening appointment.
- Previous surgical bowel resection.
- Previous lung transplant.
- Use of medications known to interact with the antimycobacterial drug levels; of note, the most common interactions in CF patients are the use of itraconazole, voriconazole, and ivacaftor. We will have subjects hold H2 blockers and proton pump inhibitors for 3 days prior to each PK study day.
- Inability to hold azithromycin: Subjects will not be excluded if they are on chronic azithromycin for immunomodulatory purposes; however, we will ask that the subjects hold the azithromycin starting at the screening visit, through a 2 week wash-out period prior to Visit 2, and remain off through the end of Visit 3 (about 4 weeks total).
- Acute exacerbations: exclusion if any addition of oral, IV, or inhaled antibiotics, or an acute gastrointestinal illness with vomiting or diarrhea in the 2 weeks prior to each visit. No exclusion for previously prescribed alternating chronic inhaled or oral antibiotics.
- We will also exclude pregnant women (urine pregnancy test will be performed for females on the day of each PK study) and decisionally challenged subjects.
Healthy Control Exclusion Criteria:
- Allergy or intolerance to rifampin, ethambutol, or azithromycin.
- Hepatic insufficiency defined as having an AST or ALT greater than three times the upper limit of normal at the screening appointment.
- Previous chronic GI disease or surgical bowel resection.
- Use of medications known to interact with the antimycobacterial drug levels. We will have subjects hold H2 blockers and proton pump inhibitors for 3 days prior to the PK study day.
- Acute illness: exclusion if respiratory illness requiring antibiotics or gastrointestinal illness with vomiting or diarrhea in the 2 weeks prior to the PK visit.
- We will also exclude pregnant women (urine pregnancy test will be performed on the day of PK study) and decisionally challenged subjects.
Study & Design
- Study Type
- INTERVENTIONAL
- Study Design
- CROSSOVER
- Arm && Interventions
Group Intervention Description Fasting Rifampin Subjects with CF will be given the antimycobacterial drugs in the fasting state, without supplemental pancreatic enzymes * Rifampin 10mg/kg oral once daily (max 600mg, round to closest 150mg) * Ethambutol 15mg/kg oral once daily (max 2500mg, round to nearest 100mg) * Azithromycin 10mg/kg oral once daily (max 500mg, rounded to the nearest 250mg) Blood will be drawn at time points 0.5, 1, 1.5, 2, 2.5, 3, 4, 6, 8, and 12 hours post dose Fasting Ethambutol Subjects with CF will be given the antimycobacterial drugs in the fasting state, without supplemental pancreatic enzymes * Rifampin 10mg/kg oral once daily (max 600mg, round to closest 150mg) * Ethambutol 15mg/kg oral once daily (max 2500mg, round to nearest 100mg) * Azithromycin 10mg/kg oral once daily (max 500mg, rounded to the nearest 250mg) Blood will be drawn at time points 0.5, 1, 1.5, 2, 2.5, 3, 4, 6, 8, and 12 hours post dose Fasting Azithromycin Subjects with CF will be given the antimycobacterial drugs in the fasting state, without supplemental pancreatic enzymes * Rifampin 10mg/kg oral once daily (max 600mg, round to closest 150mg) * Ethambutol 15mg/kg oral once daily (max 2500mg, round to nearest 100mg) * Azithromycin 10mg/kg oral once daily (max 500mg, rounded to the nearest 250mg) Blood will be drawn at time points 0.5, 1, 1.5, 2, 2.5, 3, 4, 6, 8, and 12 hours post dose Food/Enzymes Ethambutol Subjects with CF will be given the antimycobacterial drugs with a standardized meal plus a typical meal-dose of pancreatic enzymes (Pancrelipase). * Rifampin 10mg/kg oral once daily (max 600mg, round to closest 150mg) * Ethambutol 15mg/kg oral once daily (max 2500mg, round to nearest 100mg) * Azithromycin 10mg/kg oral once daily (max 500mg, rounded to the nearest 250mg) Blood will be drawn at time points 0.5, 1, 1.5, 2, 2.5, 3, 4, 6, 8, and 12 hours post dose Food/Enzymes Rifampin Subjects with CF will be given the antimycobacterial drugs with a standardized meal plus a typical meal-dose of pancreatic enzymes (Pancrelipase). * Rifampin 10mg/kg oral once daily (max 600mg, round to closest 150mg) * Ethambutol 15mg/kg oral once daily (max 2500mg, round to nearest 100mg) * Azithromycin 10mg/kg oral once daily (max 500mg, rounded to the nearest 250mg) Blood will be drawn at time points 0.5, 1, 1.5, 2, 2.5, 3, 4, 6, 8, and 12 hours post dose Food/Enzymes Pancrelipase Subjects with CF will be given the antimycobacterial drugs with a standardized meal plus a typical meal-dose of pancreatic enzymes (Pancrelipase). * Rifampin 10mg/kg oral once daily (max 600mg, round to closest 150mg) * Ethambutol 15mg/kg oral once daily (max 2500mg, round to nearest 100mg) * Azithromycin 10mg/kg oral once daily (max 500mg, rounded to the nearest 250mg) Blood will be drawn at time points 0.5, 1, 1.5, 2, 2.5, 3, 4, 6, 8, and 12 hours post dose Healthy Controls Ethambutol Healthy subjects without CF will be given the antimycobacterial drugs in the fasting state, without supplemental pancreatic enzymes * Rifampin 10mg/kg oral once daily (max 600mg, round to closest 150mg) * Ethambutol 15mg/kg oral once daily (max 2500mg, round to nearest 100mg) * Azithromycin 10mg/kg oral once daily (max 500mg, rounded to the nearest 250mg) Blood will be drawn at time points 0.5, 1, 1.5, 2, 2.5, 3, 4, 6, 8, and 12 hours post dose Food/Enzymes Azithromycin Subjects with CF will be given the antimycobacterial drugs with a standardized meal plus a typical meal-dose of pancreatic enzymes (Pancrelipase). * Rifampin 10mg/kg oral once daily (max 600mg, round to closest 150mg) * Ethambutol 15mg/kg oral once daily (max 2500mg, round to nearest 100mg) * Azithromycin 10mg/kg oral once daily (max 500mg, rounded to the nearest 250mg) Blood will be drawn at time points 0.5, 1, 1.5, 2, 2.5, 3, 4, 6, 8, and 12 hours post dose Healthy Controls Rifampin Healthy subjects without CF will be given the antimycobacterial drugs in the fasting state, without supplemental pancreatic enzymes * Rifampin 10mg/kg oral once daily (max 600mg, round to closest 150mg) * Ethambutol 15mg/kg oral once daily (max 2500mg, round to nearest 100mg) * Azithromycin 10mg/kg oral once daily (max 500mg, rounded to the nearest 250mg) Blood will be drawn at time points 0.5, 1, 1.5, 2, 2.5, 3, 4, 6, 8, and 12 hours post dose Healthy Controls Azithromycin Healthy subjects without CF will be given the antimycobacterial drugs in the fasting state, without supplemental pancreatic enzymes * Rifampin 10mg/kg oral once daily (max 600mg, round to closest 150mg) * Ethambutol 15mg/kg oral once daily (max 2500mg, round to nearest 100mg) * Azithromycin 10mg/kg oral once daily (max 500mg, rounded to the nearest 250mg) Blood will be drawn at time points 0.5, 1, 1.5, 2, 2.5, 3, 4, 6, 8, and 12 hours post dose
- Primary Outcome Measures
Name Time Method Median Maximal Drug Concentration (Cmax) 0.5, 1, 1.5, 2, 2.5, 3, 4, 6, 8, and 12 hours post dose Cmax of the oral antimycobacterial drugs (azithromycin, rifampin and ethambutol) under both fasting conditions and when taken with food plus supplemental pancreatic enzymes in subjects with pancreatic insufficient CF, compared to healthy controls.
- Secondary Outcome Measures
Name Time Method Covariates of PK Measures: Circulating Neutrophil Count baseline Circulating neutrophil count. Begin to investigate the influence of inflammation, host characteristics, and drug metabolism on the PK of the antimycobacterial drugs
Covariates of PK Measures: Creatinine baseline Creatinine. Begin to investigate the influence of inflammation, host characteristics, and drug metabolism on the PK of the antimycobacterial drugs
Other PK Measures: Median Time to Maximal Drug Concentration (Tmax) 0.5, 1, 1.5, 2, 2.5, 3, 4, 6, 8, and 12 hours post dose Tmax of the oral antimycobacterial drugs (azithromycin, rifampin and ethambutol) under both fasting conditions and when taken with food plus supplemental pancreatic enzymes in subjects with pancreatic insufficient CF, compared to healthy controls
Other PK Measures: Half-life (t1/2) 0.5, 1, 1.5, 2, 2.5, 3, 4, 6, 8, and 12 hours post dose t1/2 of the oral antimycobacterial drugs (azithromycin, rifampin and ethambutol) under both fasting conditions and when taken with food plus supplemental pancreatic enzymes in subjects with pancreatic insufficient CF, compared to healthy controls
Other PK Measures: Drug Clearance 0.5, 1, 1.5, 2, 2.5, 3, 4, 6, 8, and 12 hours post dose drug clearance of the oral antimycobacterial drugs (azithromycin, rifampin and ethambutol) under both fasting conditions and when taken with food plus supplemental pancreatic enzymes in subjects with pancreatic insufficient CF, compared to healthy controls
Reported here are the Median (range) CL in the CF fasting state compared to HC for Rifampin.Covariates of PK Measures: C-reactive Protein (CRP) baseline Median Concentration of C-reactive Protein. Begin to investigate the influence of inflammation, host characteristics, and drug metabolism on the PK of the antimycobacterial drugs.
Covariates of PK Measures: Body Mass Index baseline Body mass index (BMI). Begin to investigate the influence of inflammation, host characteristics, and drug metabolism on the PK of the antimycobacterial drugs
Area Under the Curve (AUC) 0.5, 1, 1.5, 2, 2.5, 3, 4, 6, 8, and 12 hours post dose AUC of the oral antimycobacterial drugs (azithromycin, rifampin and ethambutol) under both fasting conditions and when taken with food plus supplemental pancreatic enzymes in subjects with pancreatic insufficient CF, compared to healthy controls.
Other PK Measures: Volume of Distribution (Vd) 0.5, 1, 1.5, 2, 2.5, 3, 4, 6, 8, and 12 hours post dose Vd of the oral antimycobacterial drugs (azithromycin, rifampin and ethambutol) under both fasting conditions and when taken with food plus supplemental pancreatic enzymes in subjects with pancreatic insufficient CF, compared to healthy controls
Trial Locations
- Locations (1)
Children's Hospital Colroado
🇺🇸Aurora, Colorado, United States