Study to Assess Amphotericin B Cystetic for Inhalation (ABCI) Doses in Healthy Volunteers & People with Cystic Fibrosis

Inclusion Criteria:

Part A and Part B: Each subject must meet the following criteria to be enrolled in Part A and Part B of this study.

• Subject has signed, dated, and received a copy of the IRB/IEC-approved written ICF.

• Subject is male or female aged ≥18 to ≤55 years.

• Subject has a BMI between 18 and 32 kg/m2

• Subject has an FEV1 of >90% of predicted normal value

• Subject has normal or clinically acceptable physical examination, vital signs,clinical laboratory values, and ECG at Screening.

• Female subjects must be of non-childbearing potential or male/female subjects ofchildbearing potential agree to use highly effective contraception/preventiveexposure measures

Part C: Each subject must meet the following criteria to be enrolled in Part C of this study.

• Subject has signed, dated, and received a copy of the IRB/IEC-approved written ICF.

• Age 16 years or older

• Confirmed diagnosis of CF, including sweat chloride >60 mM.

• Subject is either: Being treated with an approved CFTR modulator for at least 28days prior to Screening, or Not being treated with a CFTR modulator

• FEV1:

• For subjects on CFTR modulators: FEV1 ≥40% and ≤90%

• For subjects not on CFTR modulators: FEV1 ≥40% and ≤100%

• Stable CF disease and treatment regiment

• Female subjects must be of non-childbearing potential or male/female subjects ofchildbearing potential agree to use highly effective contraception/preventiveexposure measures

Exclusion Criteria:

Part A and Part B: Any subject who meets any of these criteria must be excluded from Part A and Part B of this study:

• Subject has history or evidence of any clinically significant pulmonary condition

• Subject has history or evidence of any clinically significant diseases or conditions

• Subject has history of malignancy of any type

• Subject has an active COVID-19 infection within 4 weeks

• Subject is positive for human immunodeficiency virus antibodies, hepatitis B surfaceantigen, or hepatitis C antibodies, or has a positive QuantiFERON®-tuberculosis Gold (QFT-G) test for tuberculosis at Screening

• Subject has a self-reported lower respiratory tract infection within 6 weeks

• Subject has evidence of any active or suspected bacterial, viral, fungal orparasitic infections within the past 4 weeks

• A subject who is an active smoker or a former smoker

• Subject has history of alcohol or drug abuse in the past year

• Subject has tested positive for drugs (including cannabis), nicotine/cotinine,and/or alcohol use at Screening, subject has consumed alcohol within 24 hours priorto Visit 3

• Subject has participated in any clinical study or had been treated with anyinvestigational drugs within 28 days or 5 half-lives

• Female subject who is pregnant or breastfeeding.

• Subject has any episode of paradoxical bronchospasm in the past 12 months.

• Subject has pacemaker; is not in sinus rhythm; has a corrected QT interval (QTc;using Fridericia's [QTcF] formula) of >450 ms (for males) and >470 ms (for females);or has a left bundle branch block or bifascicular block.

• Subject has a pulse <40 or >100 bpm; systolic blood pressure >140 mmHg, or diastolicblood pressure >90 mmHg at Screening

• Subject has Type I or II diabetes requiring medication.

• Subject has received any vaccine within 30 days prior to Day 1.

• Subject has received any of the following immunosuppressant therapies within 6months prior to Screening: imatinib, ambrisentan, azathioprine, cyclophosphamide,cyclosporine A, bosentan, or methotrexate.

• Subject has received any antibody or therapeutic biologic product during the 6months prior to Screening.

• Subject has received any oral, intravenous, or intramuscular steroid within 4 weeksprior to Screening. Intrathecal or intraarticular steroids are permitted.

• A subject who is not vaccinated with the COVID-19 vaccine with appropriate windowfrom last dose of vaccine to Screening per local guidelines, policies, andavailability within 30 days prior to Day 1.

Part C: Any subject who meets any of these criteria must be excluded from Part C of this study:

• History of any illness or any clinical condition that might confound the results ofthe study or pose an additional risk in administering study drug(s) to the subject.

• Any of the following abnormal laboratory tests: Hemoglobin, Total bilirubin, liverenzymes or creatine clearance

• An acute upper or lower respiratory infection, pulmonary exacerbation, or changes intherapy for sinopulmonary disease within 28 days before the screening visit.

• An acute illness not related to CF within 14 days before the first dose of studydrug.

• Subject has an active COVID-19 infection within 4 weeks prior to screening.

• Ongoing or prior participation in a study of an investigational treatment within 28days or 5 terminal half-lives (whichever is longer) before screening.

• Female subject who is pregnant or breastfeeding.

Please refer to study protocol for the complete inclusion/exclusion criteria list.