Inclusion Criteria:

1. Has a prior diagnosis of NTM-PD due to MAC according to American Thoracic Society
(ATS) criteria

2. Has at least one prior lower respiratory culture (sputum or bronchoalveolar lavage
[BAL]) positive for MAC in the 12 months prior to consent

3. Has an induced sputum culture at Screening positive for MAC by quantitative culture on
solid agar

4. Is either treatment naïve and has not received any prior treatment for MAC, OR if
previously treated for MAC and meets all of the following criteria:

1. Has a history of successful treatment with sputum culture conversion to negative

2. Has recent sputum or BAL culture evidence of recurrent or relapsed disease and

3. Has been off therapy for at least 3 months prior to consent

5. Has clinical signs and symptoms within the 6 weeks prior to consent that are
consistent with NTM-PD ≥2 of the following:

1. chronic cough

2. fatigue

3. frequent throat clearing

4. shortness of breath (dyspnea)

5. coughing up of blood (hemoptysis)

6. excessive mucus (sputum) production

7. fever (temperature >38ºC or >100.4ºF)

8. night sweats

9. loss of appetite

10. unintended weight loss

11. wheezing

12. chest pain

6. Has a measured forced expiratory volume in the first second following maximal
inhalation (FEV1) % predicted ≥30% within 3 months prior to consent. If prior FEV1%
predicted test result is not available, obtain FEV1% predicted at Screening to confirm
eligibility

Exclusion Criteria:

1. In the opinion of the Investigator, is not a candidate for a 5-month delay in
initiation of standard multidrug therapy to participate in a placebo-controlled
clinical trial (e.g., participant has severe symptoms or, extensive disease burden)

2. Has disseminated or extrapulmonary NTM disease

3. Has end-stage NTM-PD or treatment-refractory NTM-PD

4. Has isolation on lower respiratory (sputum or BAL) cultures of any Mycobacterium
species other than those included in MAC within the 6 months prior to consent

5. Has any other condition or prior therapy, which, in the opinion of the Investigator,
would make the participant unsuitable for this study, including compliance with all
study assessments and adherence to the protocol schedule of assessment

6. Prior exposure to SPR720. Participants who are unable to comply with the requirements
of the study or who in the opinion of the Investigator should not participate in the
study are not eligible

- Other inclusion and exclusion criteria as per protocol may apply.

Note: Other protocol defined Inclusion/Exclusion Criteria may apply.

Eligibility last updated 2/01/2024. Questions regarding updates should be directed to the study team contact.