NCT05504837 · Krystal Biotech, Inc.
A Study Assessing KB407 for the Treatment of Cystic Fibrosis
What this study is about
This study will evaluate safety and how well patients handle the treatment of ascending doses of nebulized KB407 in adults with cystic fibrosis.
View original scientific description
This study will evaluate safety and tolerability of ascending doses of nebulized KB407 in adults with cystic fibrosis.
Who can participate
This study lists these criteria on ClinicalTrials.gov. A study coordinator reviews eligibility during screening — this page does not determine whether you qualify.
Inclusion criteria
- The subject must have read, understood, and signed an Institutional Review Board/Ethics Committee (IRB/IEC) approved Informed Consent Form and must be able to and willing to follow study procedures and instructions
- Subjects aged 18 years or older at the time of Informed Consent
- A confirmed diagnosis of CF as defined by clinical signs and symptoms of CF and at least one of the following:
- A historical sweat chloride value \>60 mmol/L
- Two copies of a disease causing mutation in the CFTR gene
- Clinically stable in the opinion of the Investigator
- Percent predicted FEV1 ≥40% and ≤90% of the predicted normal for age, gender, and height at Screening
- Resting oxygen saturation ≥92% on room air at Screening
Exclusion criteria
- Initiation of any new chronic therapy (eg, CFTR modulator, hypertonic saline, inhaled antibiotic) or any change in chronic therapy (excluding pancreatic enzyme replacement therapy) within 28 days prior to the first dose
- Hospitalization, sinopulmonary infection, CF exacerbation, or other clinically significant infection or illness 14 days prior to the first dose that, in the opinion of the Investigator, may confound study results
- Treatment for Mycobacterium abscessus within 3 months prior to the first dose or more than two pulmonary exacerbations with a history of Burkholderia cenocepacia infection within 6 months prior to the first dose
- Participation in another clinical study or treatment with an investigational agent 30 days or 5 half-lives, whichever is longer, prior to the first dose
- History of or listed for solid organ transplantation
- Any condition (including a history or current evidence of substance abuse or dependence, uncontrolled asthma, or is considered to be immunocompromised) that, in the opinion of the Investigator, would impact a subject's ability to complete all study-related procedures and/or poses an additional risk to the assessment of safety of KB407
- An active oral herpes infection 30 days prior to the first dose
- Women who are pregnant or nursing
- Subject who is unwilling to comply with contraception requirements per protocol
- Clinically significant abnormalities of hematology or chemistry testing at Screening that the Investigator believes may interfere with the assessment of safety and/or efficacy of the study treatment
- Subject has a known hypersensitivity to inhaled glycerol
- Subject is known to be noncompliant or is unlikely to comply with the requirements of the study protocol in the opinion of the Investigator
- Bronchoscopy participants only: Unable to tolerate bronchoscopy procedure and airway sampling, in the opinion of the Investigator
- Cohort 4 participants only: Subjects who are ineligible for, do not tolerate, or do not benefit from modulator therapy
Where
- Gainesville, Florida
- Boise, Idaho
- Northfield, Illinois
- Hawthorne, New York
- New York, New York
- Winston-Salem, North Carolina
Frequently asked questions
What is a clinical trial?
A clinical trial is a research study that tests new medical treatments, drugs, devices, or procedures to determine their safety and effectiveness. Trials are carefully designed and monitored to protect participants while advancing medical knowledge.
Is it safe to participate?
Clinical trials follow strict safety guidelines and ethical standards. Trials must be reviewed and approved, and participants are closely monitored by medical professionals throughout the study. You can withdraw at any time if you choose.
Will I be compensated?
Many clinical trials offer compensation for your time, travel expenses, and inconvenience. The specific compensation varies by study and will be discussed during the screening process. All study-related medical care is typically provided at no cost to participants.
Will I receive a placebo instead of treatment?
When effective treatment exists, participants typically receive either the standard treatment plus the study intervention, or the standard treatment plus placebo. You would not be denied effective care. Placebos are primarily used when no proven treatment is available, or in addition to standard care. Your trial consent form will clearly explain what treatments you may receive.
Can I leave a trial if I change my mind?
Absolutely. Participation in clinical trials is completely voluntary. You have the right to withdraw from the study at any time, for any reason, without penalty or loss of benefits to which you are otherwise entitled.
How long does a clinical trial last?
Trial duration varies widely depending on the study design and purpose. Some trials last just a few weeks, while others may continue for months or years. The study coordinator will provide specific timeline information during your screening call.
Data: ClinicalTrials.gov · synced May 7, 2026 · Source of record for eligibility and locations