Comparison of Two- Versus Three-antibiotic Therapy for Pulmonary Mycobacterium Avium Complex Disease (MAC2v3)
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ClinicalTrials.gov Identifier: NCT03672630 |
Recruitment Status :
Recruiting
First Posted : September 14, 2018
Last Update Posted : January 19, 2023
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Condition or disease | Intervention/treatment | Phase |
---|---|---|
Mycobacterium Avium Complex Nontuberculous Mycobacterium Infection | Drug: Azithromycin Drug: Ethambutol Drug: Rifampin | Phase 2 Phase 3 |
Study Type : | Interventional (Clinical Trial) |
Estimated Enrollment : | 500 participants |
Allocation: | Randomized |
Intervention Model: | Parallel Assignment |
Masking: | None (Open Label) |
Primary Purpose: | Treatment |
Official Title: | Comparison of Two- Versus Three-antibiotic Therapy for Pulmonary Mycobacterium Avium Complex Disease |
Actual Study Start Date : | February 22, 2019 |
Estimated Primary Completion Date : | February 28, 2025 |
Estimated Study Completion Date : | February 28, 2025 |

Arm | Intervention/treatment |
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Active Comparator: 2-drug regimen
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.
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Drug: Azithromycin
Azithromycin 500 MG Oral Tablet [ZITHROMAX]
Other Name: Zithromax Drug: Ethambutol Ethambutol 25 mg/kg [MYAMBUTOL]
Other Name: Myambutol |
Active Comparator: 3-drug regimen
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.
|
Drug: Azithromycin
Azithromycin 500 MG Oral Tablet [ZITHROMAX]
Other Name: Zithromax Drug: Ethambutol Ethambutol 25 mg/kg [MYAMBUTOL]
Other Name: Myambutol Drug: Rifampin Rifampin 600 MG [RIFADIN]
Other Name: Rifadin |
- 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.
- QOL-B Respiratory Symptoms Score [ Time Frame: 12 months post randomization ]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.
- NTM Symptoms Score [ Time Frame: 12 months post randomization ]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.
- PROMIS Fatigue 7a short form score [ Time Frame: 12 months post randomization ]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.
- Fatigue AE proportion [ Time Frame: Cumulative to 12 months ]Self-report, Moderate or worse
- Gastrointestinal AE proportion [ Time Frame: up to 12 months ]Self-report, Moderate or worse: Nausea, diarrhea, decreased appetite, OR abdominal pain
- Liver AE proportion [ Time Frame: up to 12 months ]Laboratory grade 2 or higher abnormality
- Macrolide resistance [ Time Frame: 12 months post randomization ]Susceptibility at last positive culture

Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the contacts provided below. For general information, Learn About Clinical Studies.
Ages Eligible for Study: | 18 Years and older (Adult, Older Adult) |
Sexes Eligible for Study: | All |
Accepts Healthy Volunteers: | No |
Inclusion Criteria:
- Culture positive pulmonary MAC meeting ATS/IDSA disease criteria
- Age over 18 years
- Ability to provide informed consent
Exclusion Criteria:
- 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
- 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

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT03672630
Contact: Haley Miller | 503-346-1548 | millehal@ohsu.edu | |
Contact: Daniel Bouchat | 503-494-2568 | johdanie@ohsu.edu |

Study Director: | Emily Henkle, PhD, MPH | Oregon Health and Science University | |
Principal Investigator: | Kevin L Winthrop, MD, MPH | Oregon Health and Science University |
Responsible Party: | Kevin Winthrop, Professor, Oregon Health and Science University |
ClinicalTrials.gov Identifier: | NCT03672630 |
Other Study ID Numbers: |
18819 PCS-2017C2-7764 ( Other Grant/Funding Number: PCORI ) |
First Posted: | September 14, 2018 Key Record Dates |
Last Update Posted: | January 19, 2023 |
Last Verified: | January 2023 |
Individual Participant Data (IPD) Sharing Statement: | |
Plan to Share IPD: | Yes |
Plan Description: | 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)). |
Supporting Materials: |
Study Protocol Statistical Analysis Plan (SAP) Analytic Code |
Time Frame: | The dataset will be available after completion of the study and publication of results. |
Access Criteria: | Third party data requests will be reviewed by a committee, and approved requests will require a DUA. |
Studies a U.S. FDA-regulated Drug Product: | Yes |
Studies a U.S. FDA-regulated Device Product: | No |
Product Manufactured in and Exported from the U.S.: | Yes |
NTM MAC mycobacteria nontuberculous mycobacteria |
azithromycin ethambutol rifampin |
Mycobacterium Infections Mycobacterium avium-intracellulare Infection Mycobacterium Infections, Nontuberculous Actinomycetales Infections Gram-Positive Bacterial Infections Bacterial Infections Bacterial Infections and Mycoses Infections Azithromycin Rifampin Ethambutol Anti-Bacterial Agents Anti-Infective Agents |
Antibiotics, Antitubercular Antitubercular Agents Leprostatic Agents Nucleic Acid Synthesis Inhibitors Enzyme Inhibitors Molecular Mechanisms of Pharmacological Action Cytochrome P-450 CYP2B6 Inducers Cytochrome P-450 Enzyme Inducers Cytochrome P-450 CYP2C8 Inducers Cytochrome P-450 CYP2C19 Inducers Cytochrome P-450 CYP2C9 Inducers Cytochrome P-450 CYP3A Inducers |