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

A 3-part Study of ABCI: a Randomized, Double-blind, Placebo-controlled, Single-ascending Dose Phase 1a Study in Healthy Volunteers (Part A), a Randomized, Double-blind, Placebo-controlled, 14- and 28-day Multiple-ascending Dose Phase 1a Study in Healthy Volunteers (Part B), and a 28-day Open-Label Phase 1b Study in Subjects with Cystic Fibrosis (Part C)

Study to Assess Amphotericin B Cystetic for Inhalation (ABCI) Doses in Healthy Volunteers & People with Cystic Fibrosis (NCT05802264) is a Phase 1 interventional studying Cystic Fibrosis, sponsored by Cystetic Medicines, Inc.. RECRUITING as of the most recent ClinicalTrials.gov update. Talk to your doctor before contacting the trial site.

About This Trial

This is a 3-part, single-ascending dose Phase 1a randomized, double-blind, placebo-controlled study in healthy volunteers (Part A) and multiple-ascending dose Phase 1a randomized, double-blind, placebo-controlled study in healthy volunteers (Part B), and a Phase 1b open-label study in subjects with CF (Part C) to assess the safety, tolerability, PK, and preliminary efficacy of ABCI. Subjects will be evaluated for eligibility during Screening within 30 days prior to Day 1 (Randomization; Visit 3). In Parts A and B, eligible healthy volunteers may be enrolled in the study and randomly allocated to treatment with ABCI or placebo as described below. In Part C, eligible subjects with CF may be enrolled in the study and receive treatment with ABCI as described below. Approximately 72 healthy subjects total will be randomized to 9 cohorts (48 subjects in 6 cohorts in Part A, 24 subjects in 3 cohorts in Part B) and approximately 36 subjects with CF will receive the low dose, medium dose (2 sentinel subjects), or high dose of ABCI in Part C.

What Stage of Research Is This?

Phase 1 trials test a new treatment for the first time in humans, focusing on safety, dosing, and how the body processes the drug. For Cystic Fibrosis, a Phase 1 study typically enrolls a small number of participants — often healthy volunteers or patients who have exhausted standard treatment options. Phase 1 results determine whether a treatment moves into larger Phase 2 efficacy studies.

This trial is currently recruiting participants. The sponsor has registered the study with ClinicalTrials.gov as actively enrolling, which means new applicants who meet the eligibility criteria can be considered for screening. Trial status can change between updates — confirm current recruiting status with the study contact before traveling for a screening visit.

Target enrollment of 108 participants puts this in the typical range for a Phase 2-style efficacy study or a moderate Phase 3 trial in a focused Cystic Fibrosis subpopulation. At this scale, the study has enough statistical power to detect a clear treatment effect but is not the largest cohort in the field.

Who May Be Eligible (Plain English)

Who May Qualify: 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 of childbearing potential agree to use highly effective contraception/preventive exposure 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 28 days 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 of childbearing potential agree to use highly effective contraception/preventive exposure measures Who Should NOT Join This Trial: 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 ...See full criteria on ClinicalTrials.gov Always talk to your doctor about whether this trial is right for you.

These are translations of the protocol\'s inclusion and exclusion criteria, simplified for patients and caregivers. The original clinical text appears below. Eligibility is ultimately confirmed by the trial site\'s screening process — this summary is a starting point for a conversation with your doctor, not a final determination.

Original Eligibility Criteria

View original clinical language

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 of childbearing potential agree to use highly effective contraception/preventive exposure 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 28 days 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 of childbearing potential agree to use highly effective contraception/preventive exposure 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 surface antigen, 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 or parasitic 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 prior to Visit 3 * Subject has participated in any clinical study or had been treated with any investigational 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 diastolic blood 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 6 months prior to Screening: imatinib, ambrisentan, azathioprine, cyclophosphamide, cyclosporine A, bosentan, or methotrexate. * Subject has received any antibody or therapeutic biologic product during the 6 months prior to Screening. * Subject has received any oral, intravenous, or intramuscular steroid within 4 weeks prior to Screening. Intrathecal or intraarticular steroids are permitted. * A subject who is not vaccinated with the COVID-19 vaccine with appropriate window from last dose of vaccine to Screening per local guidelines, policies, and availability 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 of the study or pose an additional risk in administering study drug(s) to the subject. * Any of the following abnormal laboratory tests: Hemoglobin, Total bilirubin, liver enzymes or creatine clearance * An acute upper or lower respiratory infection, pulmonary exacerbation, or changes in therapy 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 study drug. * 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 28 days 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.

Treatments Being Tested

COMBINATION_PRODUCT

ABCI

Subjects will receive ABCI via oral inhalation

COMBINATION_PRODUCT

Placebo

Subjects will receive ABCI via oral inhalation

Locations (5)

Trial sites listed on ClinicalTrials.gov for this study. Site activation status can vary — confirm with the specific site before traveling for a screening visit.

Canberra Hospital

Canberra, Australian Capital Territory, Australia

Westmead Hospital

Westmead, New South Wales, Australia

The Prince Charles Hospital

Brisbane, Queensland, Australia

Monash Medical Centre

Clayton, Victoria, Australia

New Zealand Clinical Research

Christchurch, New Zealand

How to Talk to Your Doctor About This Trial

Bring the printable summary of this trial — including the NCT ID (NCT05802264), the sponsor (Cystetic Medicines, Inc.), and the key eligibility criteria — to your next appointment. Your doctor can review the inclusion and exclusion criteria against your medical history, lab values, and current treatments to assess whether you are likely to qualify. They can also help you weigh whether trial participation makes sense alongside your existing care plan.

Useful questions to walk through together: What does the trial protocol require beyond standard care? How long is the active treatment phase, and how long is follow-up? Are there study visits at sites I can reach? Who pays for the trial-specific procedures, and who pays for standard-of-care portions? See our 25 questions to ask about clinical trials guide for a more complete checklist.

Authoritative Sources

The official record for this trial lives on ClinicalTrials.gov — the federal registry maintained by the National Library of Medicine at NIH. For background on how this trial fits into the FDA approval pathway, see the FDA drug approval process. For oncology-specific guidance for patients considering trials, the National Cancer Institute publishes patient-oriented overviews. International trial registries are aggregated by the WHO ICTRP.

Frequently Asked Questions

What is the NCT05802264 clinical trial studying?

This is a 3-part, single-ascending dose Phase 1a randomized, double-blind, placebo-controlled study in healthy volunteers (Part A) and multiple-ascending dose Phase 1a randomized, double-blind, placebo-controlled study in healthy volunteers (Part B), and a Phase 1b open-label study in subjects with CF (Part C) to assess the safety, tolerability, PK, and preliminary efficacy of ABCI. Subjects will be evaluated for eligibility during Screening within 30 days prior to Day 1 (Randomization; Visit 3). In Parts A and B, eligible healthy volunteers may be enrolled in the study and randomly allocated … The full protocol is registered on ClinicalTrials.gov and includes the primary outcome measures, eligibility criteria, and study endpoints.

Who can participate in NCT05802264?

Eligibility for this trial depends on the specific inclusion and exclusion criteria set by the sponsor. The plain-English summary above translates the most important criteria into accessible language; the official clinical text is preserved in the collapsible section underneath. Whether you fit any specific trial is a medical decision your doctor needs to confirm — bring the trial information to your treating physician for a full review against your medical history.

How do I contact the trial site for NCT05802264?

Contact information registered with ClinicalTrials.gov is shown in the sidebar of this page. Before reaching out, confirm with your treating physician that this trial is appropriate for your situation. The trial site will then walk you through the screening process to determine final eligibility.

Is participating in a clinical trial safe?

Clinical trials in the United States are regulated by the FDA and overseen by Institutional Review Boards (IRBs) that review the protocol for safety. Risk varies by trial — Phase 1 studies test new treatments in humans for the first time, while Phase 3 trials use treatments that have already passed earlier safety screening. The informed consent document for any specific trial details the known risks and what to expect. Discuss those risks with your physician before deciding whether to participate.

Where can I verify the data on this page?

Every detail on this page comes directly from the ClinicalTrials.gov API. Click "View on ClinicalTrials.gov" in the sidebar to see the official, unmodified record. The federal record is always authoritative; this page is a structured presentation with a plain-English eligibility translation. For background on how clinical trials are regulated, see the FDA drug approval process documentation.

How This Page Is Built

Every field on this page is pulled directly from the ClinicalTrials.gov API v2 — no estimates, no proxies. The plain-English eligibility translation is generated from the original protocol text and reviewed for fidelity to the underlying clinical criteria. The original clinical text remains visible in the collapsible section above so users and clinicians can verify the translation. Read the full methodology for the data pipeline and known limitations.

Source: ClinicalTrials.gov API v2 record for NCT05802264. Maintained by the National Library of Medicine at NIH. Public domain. Cite as: "TrialFinderData. NCT05802264. Data: ClinicalTrials.gov."

Medical disclaimer: This page is informational, not medical advice. Talk to your doctor about whether a clinical trial is right for you.

Last updated 2026-05-08 · Data from ClinicalTrials.gov.