Mycobacterium Avium ComplexPhase 2/3MAC2v3NCT03672630
Comparison of Two- Versus Three-antibiotic Therapy for Pulmonary Mycobacterium Avium Complex Disease
A Phase 2/3 study testing Azithromycin, Ethambutol and Rifampin in people with Mycobacterium Avium Complex and Nontuberculous Mycobacterium Infection, run by Kevin Winthrop at 26 sites in 2 countries.
Trial summary
NTM therapy consists of a multi-drug macrolide based regimen for 18-24 months. Treated patients frequently experience debilitating side effects, and many patients delay the start of antibiotic treatment due to these risks. Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Mycobacterium Avium Complex, Nontuberculous Mycobacterium Infection
- What is being tested?
- Azithromycin, Ethambutol and Rifampin
- Type of treatment
- Pill or oral medicine
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 474 participants
- Where
- 26 sitesin 2 countries
- Study dates
- 22 Feb 2019to 8 Jan 2026
- Phase
- Phase 2/3
- Are there results?
- None posted in the registry
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 years and older
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Culture positive pulmonary MAC meeting ATS/IDSA disease criteria
- Age over 18 years
- Ability to provide informed consent
Who cannot join
- Fibrocavitary disease
- Planned surgery for MAC disease
- Patients who have cumulatively taken 6 weeks or more of multi-drug antimicrobial treatment for MAC
- Patients who are currently taking or have taken multi-drug antimicrobial treatment for NTM within the prior 30 days
- Diagnosis of Cystic fibrosis
- Diagnosis of HIV
Show all 9Show fewer
- History of solid organ or hematologic transplant
- Significant drug-drug interaction not clinically manageable in the opinion of the investigator
- Contraindication to any component of the study treatment regimen
Trial locations and contacts
26 sites in 2 countries.
26 sites in 2 countries
United States25 sites
Emory University
Atlanta, Georgia, 30322
Johns Hopkins University
Baltimore, Maryland, 21224
University of North Carolina
Chapel Hill, North Carolina, 27599
Medical University of South Carolina
Charleston, South Carolina, 29425
National Jewish Health
Denver, Colorado, 80206
Kaiser Permanente Hawaii
Honolulu, Hawaii, 96817
University of Iowa
Iowa City, Iowa, 52242
University of Kansas
Kansas City, Kansas, 66160
Loma Linda University Medical Center
Loma Linda, California, 92354
University of Wisconsin School of Medicine and Public Health
Madison, Wisconsin, 53705
Northwell Health
Manhasset, New York, 11030
University of Miami
Miami, Florida, 33136
Louisina State University
New Orleans, Louisiana, 70112
New York University
New York, New York, 10016
Columbia University Medical Center
New York, New York, 10032
Temple University
Philadelphia, Pennsylvania, 19140
Oregon Health & Science University
Portland, Oregon, 97239
Mayo Clinic
Rochester, Minnesota, 55905
University of California, San Diego
San Diego, California, 92103
University of California, San Francisco
San Francisco, California, 94110
University of Washington
Seattle, Washington, 98104
Stanford University
Stanford, California, 94305
Tampa VA Medical Center
Tampa, Florida, 33612
University of Texas Health Science Center
Tyler, Texas, 75708
Vancouver Clinic
Vancouver, Washington, 98664
About this study
NTM therapy consists of a multi-drug macrolide based regimen for 18-24 months. Treated patients frequently experience debilitating side effects, and many patients delay the start of antibiotic treatment due to these risks. Common side effects include nausea, diarrhea, and fatigue, and rare but serious toxicities include ocular toxicity, hearing loss, and hematologic toxicity. To date, most of the evidence underlying the current treatment recommendations has come from observational studies in which either a macrolide has been combined with rifampin and ethambutol, or in some cases combined with ethambutol alone. The proposed study will answer whether a third drug is necessary or whether taking two drugs can increase tolerability without a substantial loss of efficacy.
Read the detailed description
Mycobacterium avium complex (MAC) are a subset of nontuberculous mycobacteria (NTM), environmental bacteria that can cause chronic, debilitating pulmonary disease, primarily affecting those over age 60. The goals of treatment are to improve symptoms, stop disease progression, and clear the infection. We propose to address a longstanding controversy in the therapy of pulmonary MAC disease, whether patients must take three antibiotics concomitantly, or if two are sufficient. The study is a multicenter randomized pragmatic clinical trial to compare azithromycin + ethambutol (2-drug therapy) vs. azithromycin + ethambutol + rifampin (3-drug therapy) for non-cavitary pulmonary MAC disease. All clinical outcomes will be considered standard of care and abstracted from clinical records. Therapy changes and adverse events will be recorded at routine visits. Health-related quality of life (HRQoL) and self-reported toxicity will be captured centrally in a web-based database, and CT scans will be read centrally. Co-primary outcomes are culture conversion and tolerability of treatment. The primary analysis for culture conversion will be conducted as a per-protocol non-inferiority analysis, and the primary analysis for tolerability will be conducted as an intention-to-treat superiority analysis.
- Being tested
- Azithromycin, Ethambutol, Rifampin
- Keywords
- NTM, MAC, mycobacteria, nontuberculous mycobacteria, azithromycin, ethambutol, rifampin
- Medical subject headings
- Mycobacterium avium-intracellulare Infection, Mycobacterium Infections, Nontuberculous, Mycobacterium Infections
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
AzithromycinDrug
Also called Zithromax
Azithromycin 500 MG Oral Tablet [ZITHROMAX]
EthambutolDrug
Also called Myambutol
Ethambutol 25 mg/kg [MYAMBUTOL]
RifampinDrug
Also called Rifadin
Rifampin 600 MG [RIFADIN]
| Study group | Role | What they receive |
|---|---|---|
| 2-drug regimen | Active comparator | This arm is a 3 time per week (TIW) treatment regimen that includes azithromycin 500 mg po + ethambutol 25 mg/kg Treatment changes are at the discretion of the treating physician and patient. Where possible, changes in dosing or frequency that allow the patient to continue taking the assigned drugs during the 12 months study period are preferred. Receives: Drug: Azithromycin; Drug: Ethambutol |
| 3-drug regimen | Active comparator | This arm is a 3 time per week (TIW) treatment regimen that includes azithromycin 500 mg po + ethambutol 25 mg/kg + rifampin 600 mg Treatment changes are at the discretion of the treating physician and patient. Where possible, changes in dosing or frequency that allow the patient to continue taking the assigned drugs during the 12 months study period are preferred. Receives: Drug: Azithromycin; Drug: Ethambutol; Drug: Rifampin |
What is being measured
The primary outcome is the main question the study is designed to answer.
Acid-fast bacilli (AFB) culture negativity
Two consecutive negative AFB cultures by 12 months post randomization without reversion to positive
Measured: 12 months post randomization
Therapy completion
The proportion of patients who complete 12 months of therapy on their assigned regimen with "satisfactory adherence". "Satisfactory adherence" is defined as taking 80% of their prescribed doses/not missing more than 75 days of treatment.
Measured: 12 months post randomization
Secondary outcomes (7)
QOL-B Respiratory Symptoms Score
Quality of Life-Bronchiectasis (QOL-B) with NTM module The QOL-B is a self-administered questionnaire that has been validated in patients with bronchiectasis. The questionnaire measures 8 separate domains: Physical Functioning, Role Functioning, Vitality, Emotional Functioning, Social Functioning, Treatment Burden, Health Perceptions, and Respiratory Symptoms.
Measured: 12 months post randomization
NTM Symptoms Score
Quality of Life-Bronchiectasis (QOL-B) with NTM module The QOL-B is a self-administered questionnaire that has been validated in patients with bronchiectasis. The NTM module includes 4 additional domains: Eating Problems, Body Image, Digestive Symptoms, and NTM Symptoms. No total score is calculated.
Measured: 12 months post randomization
PROMIS Fatigue 7a short form score
PROMIS Fatigue 7a short form score The PROMIS Fatigue item banks assess a range of self-reported symptoms over the past seven days, from mild subjective feelings of tiredness to an overwhelming, debilitating, and sustained sense of exhaustion that likely decreases one's ability to execute daily activities and function normally in family or social roles. Fatigue is divided into the experience of fatigue (frequency, duration, and intensity) and the impact of fatigue on physical, mental, and social activities. Each question has five response options ranging in value from one to five. To find the total raw score for a short form with all questions answered, sum the values of the response to each question. The lowest possible raw score (indicating the highest subjective level of fatigue) is 7; and the highest possible raw score (indicating the lowest subjective level of fatigue) is 35.
Measured: 12 months post randomization
Fatigue AE proportion
Self-report, Moderate or worse
Measured: Cumulative to 12 months
Gastrointestinal AE proportion
Self-report, Moderate or worse: Nausea, diarrhea, decreased appetite, OR abdominal pain
Measured: up to 12 months
Liver AE proportion
Laboratory grade 2 or higher abnormality
Measured: up to 12 months
Macrolide resistance
Susceptibility at last positive culture
Measured: 12 months post randomization
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted14 Sep 2018
- Study start22 Feb 2019
- Primary completion8 Jan 2026
- Study completion8 Jan 2026
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (20)Papers the sponsor has linked to this study.
- Other trials for Mycobacterium Avium ComplexStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase 2/3
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Enrolment
- 474 participants (actual)
Sponsor and investigators
- Lead sponsor
- Kevin Winthrop
- Sponsor type
- University, hospital or other
- Collaborators
- Patient-Centered Outcomes Research Institute, National Jewish Health, The University of Texas Health Science Center at Tyler, University Health Network, Toronto, New York University, Medical University of South Carolina, Mayo Clinic, Louisiana State University Health Sciences Center in New Orleans, University of California, San Diego, Stanford University, University of Kansas, Vancouver Clinic, University of California, San Francisco, University of Washington, Johns Hopkins University, University of Miami, Emory University, University of Iowa, University of North Carolina, Temple University, Loma Linda University, Columbia University, University of Wisconsin, Madison, Northwell Health, Kaiser Permanente, James A. Haley Veterans Administration Hospital
- Responsible party
- Sponsor-investigator, Kevin Winthrop, Oregon Health and Science University
- Investigators
- Emily Henkle, PhD, MPH, Study director, Oregon Health and Science UniversityKevin L Winthrop, MD, MPH, Principal investigator, Oregon Health and Science University
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT03672630
- Sponsor's protocol ID
- 18819
- Other IDs
- PCS-2017C2-7764
- Acronym
- MAC2v3
- Status last verified
- Jan 2026
- First submitted
- 11 Sep 2018
- Last updated
- 2 Feb 2026
- Results posted
- No
- FDA-regulated drug
- Yes
- FDA-regulated device
- No
- Individual data sharing
- Yes: A Full Data Package will be made available in a PCORI-designated repository. The Full Data Package includes the Analyzable Data Set, Full Protocol, metadata, data dictionary, full statistical analysis plan (including all amendments and all documentation for additional work processes), and analytic code from the PCORI-funded research project. The Analyzable Dataset includes a final cleaned and locked data set that contains all the data used in conducting the analyses reported in the PCORI Final Research Report and is de-identified in accordance with the HIPAA Privacy Rule (45 C.F.R. § 164.514(b)).
Publications
Henkle E, Hedberg K, Schafer S, Novosad S, Winthrop KL. Population-based Incidence of Pulmonary Nontuberculous Mycobacterial Disease in Oregon 2007 to 2012. Ann Am Thorac Soc. 2015 May;12(5):642-7. doi: 10.1513/AnnalsATS.201412-559OC.
PubMed 25692495Prevots DR, Shaw PA, Strickland D, Jackson LA, Raebel MA, Blosky MA, Montes de Oca R, Shea YR, Seitz AE, Holland SM, Olivier KN. Nontuberculous mycobacterial lung disease prevalence at four integrated health care delivery systems. Am J Respir Crit Care Med. 2010 Oct 1;182(7):970-6. doi: 10.1164/rccm.201002-0310OC. Epub 2010 Jun 10.
PubMed 20538958Winthrop KL, McNelley E, Kendall B, Marshall-Olson A, Morris C, Cassidy M, Saulson A, Hedberg K. Pulmonary nontuberculous mycobacterial disease prevalence and clinical features: an emerging public health disease. Am J Respir Crit Care Med. 2010 Oct 1;182(7):977-82. doi: 10.1164/rccm.201003-0503OC. Epub 2010 May 27.
PubMed 20508209Griffith DE, Aksamit T, Brown-Elliott BA, Catanzaro A, Daley C, Gordin F, Holland SM, Horsburgh R, Huitt G, Iademarco MF, Iseman M, Olivier K, Ruoss S, von Reyn CF, Wallace RJ Jr, Winthrop K; ATS Mycobacterial Diseases Subcommittee; American Thoracic Society; Infectious Disease Society of America. An official ATS/IDSA statement: diagnosis, treatment, and prevention of nontuberculous mycobacterial diseases. Am J Respir Crit Care Med. 2007 Feb 15;175(4):367-416. doi: 10.1164/rccm.200604-571ST. No abstract available.
PubMed 17277290Griffith DE, Brown-Elliott BA, Shepherd S, McLarty J, Griffith L, Wallace RJ Jr. Ethambutol ocular toxicity in treatment regimens for Mycobacterium avium complex lung disease. Am J Respir Crit Care Med. 2005 Jul 15;172(2):250-3. doi: 10.1164/rccm.200407-863OC. Epub 2005 Apr 28.
PubMed 15860751Lee H, Sohn YM, Ko JY, Lee SY, Jhun BW, Park HY, Jeon K, Kim DH, Kim SY, Choi JE, Moon IJ, Shin SJ, Park HJ, Koh WJ. Once-daily dosing of amikacin for treatment of Mycobacterium abscessus lung disease. Int J Tuberc Lung Dis. 2017 Jul 1;21(7):818-824. doi: 10.5588/ijtld.16.0791.
PubMed 28633708Peloquin CA, Berning SE, Nitta AT, Simone PM, Goble M, Huitt GA, Iseman MD, Cook JL, Curran-Everett D. Aminoglycoside toxicity: daily versus thrice-weekly dosing for treatment of mycobacterial diseases. Clin Infect Dis. 2004 Jun 1;38(11):1538-44. doi: 10.1086/420742. Epub 2004 May 5.
PubMed 15156439Winthrop KL, Ku JH, Marras TK, Griffith DE, Daley CL, Olivier KN, Aksamit TR, Varley CD, Mackey K, Prevots DR. The tolerability of linezolid in the treatment of nontuberculous mycobacterial disease. Eur Respir J. 2015 Apr;45(4):1177-9. doi: 10.1183/09031936.00169114. Epub 2015 Jan 22. No abstract available.
PubMed 25614169Miwa S, Shirai M, Toyoshima M, Shirai T, Yasuda K, Yokomura K, Yamada T, Masuda M, Inui N, Chida K, Suda T, Hayakawa H. Efficacy of clarithromycin and ethambutol for Mycobacterium avium complex pulmonary disease. A preliminary study. Ann Am Thorac Soc. 2014 Jan;11(1):23-9. doi: 10.1513/AnnalsATS.201308-266OC.
PubMed 24298907Griffith DE, Adjemian J, Brown-Elliott BA, Philley JV, Prevots DR, Gaston C, Olivier KN, Wallace RJ Jr. Semiquantitative Culture Analysis during Therapy for Mycobacterium avium Complex Lung Disease. Am J Respir Crit Care Med. 2015 Sep 15;192(6):754-60. doi: 10.1164/rccm.201503-0444OC.
PubMed 26068042Kobashi Y, Matsushima T, Oka M. A double-blind randomized study of aminoglycoside infusion with combined therapy for pulmonary Mycobacterium avium complex disease. Respir Med. 2007 Jan;101(1):130-8. doi: 10.1016/j.rmed.2006.04.002. Epub 2006 Jun 5.
PubMed 16750618Wallace RJ Jr, Brown-Elliott BA, McNulty S, Philley JV, Killingley J, Wilson RW, York DS, Shepherd S, Griffith DE. Macrolide/Azalide therapy for nodular/bronchiectatic mycobacterium avium complex lung disease. Chest. 2014 Aug;146(2):276-282. doi: 10.1378/chest.13-2538.
PubMed 24457542Adjemian J, Prevots DR, Gallagher J, Heap K, Gupta R, Griffith D. Lack of adherence to evidence-based treatment guidelines for nontuberculous mycobacterial lung disease. Ann Am Thorac Soc. 2014 Jan;11(1):9-16. doi: 10.1513/AnnalsATS.201304-085OC.
PubMed 24236749Koh WJ, Moon SM, Kim SY, Woo MA, Kim S, Jhun BW, Park HY, Jeon K, Huh HJ, Ki CS, Lee NY, Chung MJ, Lee KS, Shin SJ, Daley CL, Kim H, Kwon OJ. Outcomes of Mycobacterium avium complex lung disease based on clinical phenotype. Eur Respir J. 2017 Sep 27;50(3):1602503. doi: 10.1183/13993003.02503-2016. Print 2017 Sep.
PubMed 28954780Hernan MA, Robins JM. Per-Protocol Analyses of Pragmatic Trials. N Engl J Med. 2017 Oct 5;377(14):1391-1398. doi: 10.1056/NEJMsm1605385. No abstract available.
PubMed 28976864
Study at a glance
From the registry record, last updated by the sponsor on 2 Feb 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Comparison of Two- Versus Three-antibiotic Therapy for Pulmonary Mycobacterium Avium Complex Disease
- ClinicalTrials.gov ID
- NCT03672630
- Acronym / sponsor ID
- MAC2v3 / 18819
- Keywords
- NTM, MAC, mycobacteria, nontuberculous mycobacteria, azithromycin, ethambutol, rifampin
- Phase
- Phase 2/3
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 474 participants (actual)
- Lead sponsor
- Kevin WinthropUniversity, hospital or other
- Collaborators
- Patient-Centered Outcomes Research Institute, National Jewish Health, The University of Texas Health Science Center at Tyler, University Health Network, Toronto, New York University, Medical University of South Carolina, Mayo Clinic, Louisiana State University Health Sciences Center in New Orleans, University of California, San Diego, Stanford University, University of Kansas, Vancouver Clinic, University of California, San Francisco, University of Washington, Johns Hopkins University, University of Miami, Emory University, University of Iowa, University of North Carolina, Temple University, Loma Linda University, Columbia University, University of Wisconsin, Madison, Northwell Health, Kaiser Permanente, James A. Haley Veterans Administration Hospital
- Study start
- 22 Feb 2019 (actual)
- Primary completion
- 8 Jan 2026 (actual)
- Study completion
- 8 Jan 2026 (actual)
- First posted
- 14 Sep 2018 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
NTM therapy consists of a multi-drug macrolide based regimen for 18-24 months. Treated patients frequently experience debilitating side effects, and many patients delay the start of antibiotic treatment due to these risks. Common side effects include nausea, diarrhea, and fatigue, and rare but serious toxicities include ocular toxicity, hearing loss, and hematologic toxicity. To date, most of the evidence underlying the current treatment recommendations has come from observational studies in which either a macrolide has been combined with rifampin and ethambutol, or in some cases combined with ethambutol alone. The proposed study will answer whether a third drug is necessary or whether taking two drugs can increase tolerability without a substantial loss of efficacy.
Detailed description
Mycobacterium avium complex (MAC) are a subset of nontuberculous mycobacteria (NTM), environmental bacteria that can cause chronic, debilitating pulmonary disease, primarily affecting those over age 60. The goals of treatment are to improve symptoms, stop disease progression, and clear the infection. We propose to address a longstanding controversy in the therapy of pulmonary MAC disease, whether patients must take three antibiotics concomitantly, or if two are sufficient. The study is a multicenter randomized pragmatic clinical trial to compare azithromycin + ethambutol (2-drug therapy) vs. azithromycin + ethambutol + rifampin (3-drug therapy) for non-cavitary pulmonary MAC disease. All clinical outcomes will be considered standard of care and abstracted from clinical records. Therapy changes and adverse events will be recorded at routine visits. Health-related quality of life (HRQoL) and self-reported toxicity will be captured centrally in a web-based database, and CT scans will be read centrally. Co-primary outcomes are culture conversion and tolerability of treatment. The primary analysis for culture conversion will be conducted as a per-protocol non-inferiority analysis, and the primary analysis for tolerability will be conducted as an intention-to-treat superiority analysis.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| 2-drug regimen | Active comparator | Drug: Azithromycin, Drug: EthambutolThis arm is a 3 time per week (TIW) treatment regimen that includes azithromycin 500 mg po + ethambutol 25 mg/kg Treatment changes are at the discretion of the treating physician and patient. Where possible, changes in dosing or frequency that allow the patient to continue taking the assigned drugs during the 12 months study period are preferred. |
| 3-drug regimen | Active comparator | Drug: Azithromycin, Drug: Ethambutol, Drug: RifampinThis arm is a 3 time per week (TIW) treatment regimen that includes azithromycin 500 mg po + ethambutol 25 mg/kg + rifampin 600 mg Treatment changes are at the discretion of the treating physician and patient. Where possible, changes in dosing or frequency that allow the patient to continue taking the assigned drugs during the 12 months study period are preferred. |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (3 listed)
- Culture positive pulmonary MAC meeting ATS/IDSA disease criteria
- Age over 18 years
- Ability to provide informed consent
Key exclusion criteria (9 listed)
- Fibrocavitary disease
- Planned surgery for MAC disease
- Patients who have cumulatively taken 6 weeks or more of multi-drug antimicrobial treatment for MAC
- Patients who are currently taking or have taken multi-drug antimicrobial treatment for NTM within the prior 30 days
- Diagnosis of Cystic fibrosis
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| AzithromycinAlso: ZithromaxAzithromycin 500 MG Oral Tablet [ZITHROMAX] | Drug | 2-drug regimen, 3-drug regimen |
| EthambutolAlso: MyambutolEthambutol 25 mg/kg [MYAMBUTOL] | Drug | 2-drug regimen, 3-drug regimen |
| RifampinAlso: RifadinRifampin 600 MG [RIFADIN] | Drug | 3-drug regimen |
Primary outcome
Acid-fast bacilli (AFB) culture negativity
Time frame: 12 months post randomization
Two consecutive negative AFB cultures by 12 months post randomization without reversion to positive
Therapy completion
Time frame: 12 months post randomization
The proportion of patients who complete 12 months of therapy on their assigned regimen with "satisfactory adherence". "Satisfactory adherence" is defined as taking 80% of their prescribed doses/not missing more than 75 days of treatment.
7 secondary outcomes
QOL-B Respiratory Symptoms Score
Time frame: 12 months post randomization
NTM Symptoms Score
Time frame: 12 months post randomization
PROMIS Fatigue 7a short form score
Time frame: 12 months post randomization
Fatigue AE proportion
Time frame: Cumulative to 12 months
Gastrointestinal AE proportion
Time frame: up to 12 months
Liver AE proportion
Time frame: up to 12 months
Macrolide resistance
Time frame: 12 months post randomization
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 2 Feb 2026.
- Background: PubMed 25692495Henkle E, Hedberg K, Schafer S, Novosad S, Winthrop KL. Population-based Incidence of Pulmonary Nontuberculous Mycobacterial Disease in Oregon 2007 to 2012. Ann Am Thorac Soc. 2015 May;12(5):642-7. doi: 10.1513/AnnalsATS.201412-559OC.
- Background: PubMed 20538958Prevots DR, Shaw PA, Strickland D, Jackson LA, Raebel MA, Blosky MA, Montes de Oca R, Shea YR, Seitz AE, Holland SM, Olivier KN. Nontuberculous mycobacterial lung disease prevalence at four integrated health care delivery systems. Am J Respir Crit Care Med. 2010 Oct 1;182(7):970-6. doi: 10.1164/rccm.201002-0310OC. Epub 2010 Jun 10.
- Background: PubMed 20508209Winthrop KL, McNelley E, Kendall B, Marshall-Olson A, Morris C, Cassidy M, Saulson A, Hedberg K. Pulmonary nontuberculous mycobacterial disease prevalence and clinical features: an emerging public health disease. Am J Respir Crit Care Med. 2010 Oct 1;182(7):977-82. doi: 10.1164/rccm.201003-0503OC. Epub 2010 May 27.
- Background: PubMed 17277290Griffith DE, Aksamit T, Brown-Elliott BA, Catanzaro A, Daley C, Gordin F, Holland SM, Horsburgh R, Huitt G, Iademarco MF, Iseman M, Olivier K, Ruoss S, von Reyn CF, Wallace RJ Jr, Winthrop K; ATS Mycobacterial Diseases Subcommittee; American Thoracic Society; Infectious Disease Society of America. An official ATS/IDSA statement: diagnosis, treatment, and prevention of nontuberculous mycobacterial diseases. Am J Respir Crit Care Med. 2007 Feb 15;175(4):367-416. doi: 10.1164/rccm.200604-571ST. No abstract available.
- Background: PubMed 15860751Griffith DE, Brown-Elliott BA, Shepherd S, McLarty J, Griffith L, Wallace RJ Jr. Ethambutol ocular toxicity in treatment regimens for Mycobacterium avium complex lung disease. Am J Respir Crit Care Med. 2005 Jul 15;172(2):250-3. doi: 10.1164/rccm.200407-863OC. Epub 2005 Apr 28.
- Background: PubMed 28633708Lee H, Sohn YM, Ko JY, Lee SY, Jhun BW, Park HY, Jeon K, Kim DH, Kim SY, Choi JE, Moon IJ, Shin SJ, Park HJ, Koh WJ. Once-daily dosing of amikacin for treatment of Mycobacterium abscessus lung disease. Int J Tuberc Lung Dis. 2017 Jul 1;21(7):818-824. doi: 10.5588/ijtld.16.0791.
- Background: PubMed 15156439Peloquin CA, Berning SE, Nitta AT, Simone PM, Goble M, Huitt GA, Iseman MD, Cook JL, Curran-Everett D. Aminoglycoside toxicity: daily versus thrice-weekly dosing for treatment of mycobacterial diseases. Clin Infect Dis. 2004 Jun 1;38(11):1538-44. doi: 10.1086/420742. Epub 2004 May 5.
- Background: PubMed 25614169Winthrop KL, Ku JH, Marras TK, Griffith DE, Daley CL, Olivier KN, Aksamit TR, Varley CD, Mackey K, Prevots DR. The tolerability of linezolid in the treatment of nontuberculous mycobacterial disease. Eur Respir J. 2015 Apr;45(4):1177-9. doi: 10.1183/09031936.00169114. Epub 2015 Jan 22. No abstract available.
- Background: PubMed 24298907Miwa S, Shirai M, Toyoshima M, Shirai T, Yasuda K, Yokomura K, Yamada T, Masuda M, Inui N, Chida K, Suda T, Hayakawa H. Efficacy of clarithromycin and ethambutol for Mycobacterium avium complex pulmonary disease. A preliminary study. Ann Am Thorac Soc. 2014 Jan;11(1):23-9. doi: 10.1513/AnnalsATS.201308-266OC.
- Background: PubMed 26068042Griffith DE, Adjemian J, Brown-Elliott BA, Philley JV, Prevots DR, Gaston C, Olivier KN, Wallace RJ Jr. Semiquantitative Culture Analysis during Therapy for Mycobacterium avium Complex Lung Disease. Am J Respir Crit Care Med. 2015 Sep 15;192(6):754-60. doi: 10.1164/rccm.201503-0444OC.
- Background: PubMed 16750618Kobashi Y, Matsushima T, Oka M. A double-blind randomized study of aminoglycoside infusion with combined therapy for pulmonary Mycobacterium avium complex disease. Respir Med. 2007 Jan;101(1):130-8. doi: 10.1016/j.rmed.2006.04.002. Epub 2006 Jun 5.
- Background: PubMed 24457542Wallace RJ Jr, Brown-Elliott BA, McNulty S, Philley JV, Killingley J, Wilson RW, York DS, Shepherd S, Griffith DE. Macrolide/Azalide therapy for nodular/bronchiectatic mycobacterium avium complex lung disease. Chest. 2014 Aug;146(2):276-282. doi: 10.1378/chest.13-2538.
- Individual participant dataSharing planned: Yes. A Full Data Package will be made available in a PCORI-designated repository. The Full Data Package includes the Analyzable Data Set, Full Protocol, metadata, data dictionary, full statistical analysis plan (including all amendments and all documentation for additional work processes), and analytic code from the PCORI-funded research project. The Analyzable Dataset includes a final cleaned and locked data set that contains all the data used in conducting the analyses reported in the PCORI Final Research Report and is de-identified in accordance with the HIPAA Privacy Rule (45 C.F.R. § 164.514(b)).
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Mycobacterium Infections
RecruitingPhase 4
Prevention of Recurrence With Cordyceps Sinensis in Mycobacterium Avium Complex Pulmonary Disease
Mycobacterium Avium Complex Pulmonary Disease
RecruitingPhase 4
Short-term Bactericidal Effect of Contezolid in MAC-PD
Mycobacterium Avium Complex Pulmonary Disease
RecruitingObservational study
Pathogenesis and Genetics of Microphthalmia, Anophthalmia and Uveal Coloboma (MAC)
Coloboma, Anophthalmia
Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Emily Henkle, PhD, MPH study director
Oregon Health and Science University
Kevin L Winthrop, MD, MPH principal investigator
Oregon Health and Science University
26 sites in 2 countries: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 2/3 study testing Azithromycin, Ethambutol and Rifampin in people with Mycobacterium Avium Complex and Nontuberculous Mycobacterium Infection, run by Kevin Winthrop at 26 sites in 2 countries.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 3 inclusion and 9 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 2 Feb 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 26 sites in United States, Canada. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
What does this combined phase mean?
Phase 2 studies give the treatment to a larger group to see whether it has the intended effect and to keep checking safety.
Phase 3 studies compare the treatment with the current standard treatment or a placebo in a large group, to confirm how well it works and watch for side effects.
Not every study follows the same path, and some studies (observational studies, device studies) have no phase.
Are results available for this study?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Acid-fast bacilli (AFB) culture negativity (time frame: 12 months post randomization). The study lists 2 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT03672630, which also lists 20 linked publications.
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 2 Feb 2026.