Pharmacokinetic Study of Minocycline in Patients With Pulmonary Nontuberculous Mycobacterial Disease

Inclusion Criteria: * 2020 guideline (ATS/ERS/ESCMID/IDSA) diagnostic criteria for nontuberculous mycobacterial pulmonary disease are met, i.e. the patient is symptomatic, has nodules, bronchiectasis or fibro-cavitary lesions seen on (HR)CT scan of the lungs and ≥2 positive sputum cultures or one positive bronchoalveolar lavage culture of the same M. avium complex species. * At least one of the positive cultures must be done in the last 4 months before inclusion. * The subject is eligible to start the guideline-recommended rifampicin-based regimen according to the treating physician. * Age ≥ 18 years. * Signed and dated patient informed consent. Exclusion Criteria: * A relevant medical history or current condition that might interfere with drug absorption, distribution, metabolism or excretion (i.e. chronic gastro-intestinal disease, renal or hepatic disease). * Diagnosed with cystic fibrosis (as this may affect the pharmacokinetics of drugs). * Pregnant or breastfeeding (contra-indications for minocycline) or inadequate contraceptive measures (in view of the administration of rifampicin which interacts with oral contraceptive drugs, adequate contraceptive measures are abstinence from sexual activities and barrier methods). * Use of drugs that cause a relevant drug interaction with minocycline, i.e. oral magnesium, , bismuth, aluminium, calcium, zinc or iron containing formulations, antacid drugs and drugs besides rifampicin that are strong inducers of metabolic enzymes, including barbiturates, carbamazepin and phenytoin (as judged by the investigators). * ALAT \> 3 times the upper limit of normal (normal \<45 U/l). * ASAT \> 3 times the upper limit of normal (normal \<35 U/l). * An abnormal serum creatinine level (defined as a level that is higher than the upper limit of normal, i.e. \>110 umol/l). * Active alcohol abuse. * Hypersensitivity to minocycline or to other tetracycline antibiotics.