Recombinant Interleukin-7 (CYT107) to Treat Patients With Refractory Nontuberculous Mycobacterial Lung Disease

Inclusion Criteria: 1. Males and females aged ≥18 years but \<85 years who have given written informed consent to participate 2. Diagnosis of pulmonary nontuberculous mycobacterial lung disease in accordance with the 2007 Infectious DiseasesSociety of America (IDSA) and AmericanThoracic Society (ATS) criteria with evidence of nodular bronchiectatic and/or cavitary disease by chest CT 3. History of chronic, refractory infection with either Mycobacterium avium complex, defined as: 1. Persistently positive mycobacterial sputum cultures after 6 or more months of guideline-based treatment (GBT), with at least one positive sputum culture within 2 months prior to the baseline visit and 2. Currently on a stable guideline-based therapy that has been unchanged for the past 28 days. (GBT defined as a multi-drug regimen containing a macrolide and at least one other antimicrobial with activity against NTM.) 4. Ability to produce at least 3 mL of sputum or be willing to undergo an induction to produce at least 3 mL of sputum for clinical evaluation 5. This study permits the re-enrollment of a participant who may have been discontinued as a pre-treatment screen failure prior to study drug treatment. 6. Age and reproductive status: 1. Women of childbearing potential (WOCBP) must have a negative serum or urine pregnancy test (minimum sensitivity 25 IU/L or equivalent units of HCG) within 24 hours prior to the start of study treatment 2. Women must not be breastfeeding 3. Women of childbearing potential (WOCBP) must agree to follow instructions for method(s) of contraception for the duration of treatment with CYT107 plus 5 half-lives of CYT107 (the terminal half-life of CYT107 is up to 2 days) plus 30 days (duration of ovulatory cycle) for a total of 2 months post-treatment completion. 4. Males who are sexually active with WOCBP must agree to follow instructions for method(s) of contraception for the duration of treatment with CYT107 plus 5 half-lives of CYT107 plus 90 days (duration of sperm turnover) for a total of 7 months post-treatment completion. In addition, male participants must be willing to refrain from sperm donation during this time. 5. Azoospermic males are exempt from contraceptive requirements. 6. WOCBP who are continuously not heterosexually active are also exempt from contraceptive requirements but still must undergo pregnancy testing as described in this section. Exclusion Criteria: 1. Cancer with current chemotherapy or radiotherapy (receipt of chemotherapy or radiotherapy for cancer within the last 6 months). All patients with current, or history of, hematologic malignancy (including, but not limited to, acute lymphoblastic leukemia (ALL), acute myeloid leukemia (AML), chronic lymphocytic leukemia (CLL), chronic myeloid leukemia (CML), etc.) or lymphoma will be excluded, regardless of receipt of recent chemotherapy 2. Active pulmonary tuberculosis requiring concomitant treatment at the time of screening 3. Patients with history or current evidence of autoimmune disease including for example: myasthenia gravis, Guillain Barre syndrome, systemic lupus erythematosus, multiple sclerosis, scleroderma, ulcerative colitis, Crohn's disease, autoimmune hepatitis, Wegener's etc. 4. Patients who have received solid organ transplant or bone marrow transplant 5. Known history of infection with HIV or HIV positive test at screening 6. Known history of chronic HBV (hepatitis B viral) infection and not on treatment with HBV nucleoside analogues prior to the current hospitalization or HBV DNA \> 100 IU/mL 7. Known history of infection with HCV (hepatitis C virus) and currently undergoing treatment for HCV infections or has detectable HCV RNA 8. History of splenectomy 9. Any hematologic disease associated with hypersplenism, such as thalassemia, hereditary spherocytosis, Gaucher's Disease, and autoimmune hemolytic anemia 10. Significant liver or renal dysfunction as evidence by at least 5 times greater than the upper limits of normal baseline ALT (alanine aminotransferase), AST (aspartate aminotransferase), alkaline phosphatase, or total bilirubin. 11. Evidence of biliary cirrhosis with portal hypertension 12. Participation in another investigational interventional study testing a drug or a medical device concurrently or within the last 28 days prior to study entry 13. Patients receiving immunosuppressive drugs or concurrent immunotherapy or biologic agents; including: growth factors, cytokines and interleukins other than the study medication: Interleukin-2, Interferons α, β and γ, GM-CSF, G-CSF (colony stimulating factors), HIV vaccines, biologics including TNF alpha inhibitors (i.e. abatacept, adalimumab, anakinra, certolizumab, etanercept, golimumab, infliximab, ixekizumab, natalizumab, rituximab, secukinumab, tocilizumab, ustekinumab, vedolizumab, basiliximab and daclizumab), calcineurin inhibitors, mammalian target of rapamycin inhibitors, inosine monophosphate dehydrogenase inhibitors, Janus kinase inhibitors, hydroxyurea, immunoglobulins, adoptive cell therapy 14. Patients receiving corticosteroids at a dose greater than 300mg hydrocortisone/ day or 25 mgs of prednisone per day or equivalent for more than 3 weeks 15. Prior exposure to exogenous IL 7 16. Inability to comply with the study treatment, study visits, and study procedures as assessed by the study PI or delegate 17. Subjects with hemoptysis of ≥60 mL in a 24 hour period within 4 weeks prior to screening 18. Addition of any new antimicrobial drug with known activity against Mycobacterium avium complex infection (i.e. amikacin, azithromycin, bedaquiline, clarithromycin, ciprofloxacin, clofazimine, ethambutol, eravacycline, levofloxacin, linezolid, moxifloxacin, omadacycline, rifampin, rifabutin, tedizolid, tigecycline tobramycin) within 28 days prior to Study Day 1 19. Daily continuous oxygen supplementation \>4 L/min 20. Patients unlikely to survive a minimum of 30 days defined by (Systolic blood pressure) SBP\<90 or hypoxia \<80% SpO2 (oxygen saturation) -