Tests inhaled KB407 for cystic fibrosis in adults
Tests safety of an inhaled gene therapy at rising doses in adults with cystic fibrosis.
Plain-language title generated from the registry record
Registry title: A Study Assessing KB407 for the Treatment of Cystic Fibrosis
Key facts
- Where
- Boise, Gainesville, Hawthorne, New York, Northfield, and Winston-Salem, United StatesSee the 6 sites
- Phase
- Phase 1
AI summary: who the study is looking for
From the trial's eligibility criteria. Machine-read from the registry text on this page, so it can be wrong. The registry text below and the trial team decide who can take part.
The trial is looking for adults with cystic fibrosis who are clinically stable and have moderately reduced lung function. It tests the safety of inhaled KB407.
- Age
- 18 years or older
- Sex
- All sexes can join.
- Disease stage
- Confirmed cystic fibrosis, clinically stable, with FEV1 (lung function) between 40% and 90% of the predicted normal value, and resting oxygen saturation of 92% or more on room air.
- Earlier treatment
- No new or changed long-term cystic fibrosis treatment (for example a CFTR modulator, hypertonic saline or an inhaled antibiotic) within 28 days before the first dose. No other investigational drug within 30 days or 5 half-lives, whichever is longer.
- Biomarker or test result
- Sweat chloride above 60 mmol/L in the past, or two copies of a disease-causing mutation in the CFTR gene.
Main reasons for not taking part
- History of solid organ transplant, or on a transplant list
- Pregnant or nursing women
- Hospitalization, lung infection or cystic fibrosis flare-up within 14 days before the first dose
- Active oral herpes infection within 30 days before the first dose
- Known allergy to inhaled glycerol
Read by machine on 9 November 2026.
Where in United States
- St. Lukes CF Center of IdahoBoise, United StatesTaking people
- University of Florida - GainesvilleGainesville, United StatesTaking people
- New York Medical College/ Boston Children's Health PhysiciansHawthorne, United StatesTaking people
- Northwell Health PhysiciansNew York, United StatesTaking people
- The Cystic Fibrosis InstituteNorthfield, United StatesTaking people
- Atrium Health Wake Forest Baptist Medical CenterWinston-Salem, United StatesTaking people
Questions to ask the study team
- How often do I need to come in, and for how long each time?
- Are travel costs paid?
- Can I keep my own doctor?
- What happens if I want to stop?
Trial details
- Who runs it
- Krystal Biotech, Inc.
- Trial code
- NCT05504837
- Record updated
- 7 May 2026
- Original description
This study will evaluate safety and tolerability of ascending doses of nebulized KB407 in adults with cystic fibrosis.Read full original descriptionShow less
KB407-02 A Phase 1 Study of Inhaled KB407, a Replication-Defective, Non-Integrating Vector Expressing Human Cystic Fibrosis Transmembrane Conductance Regulator, for the Treatment of Cystic Fibrosis
This study will evaluate safety and tolerability of ascending doses of nebulized KB407 in adults with cystic fibrosis.
Inclusion: 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: 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; An active oral herpes infection 30 days prior to the first dose; Cohort 4 participants only: Subjects who are ineligible for, do not tolerate, or do not benefit from modulator therapy; 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; Subject has a known hypersensitivity to inhaled glycerol; 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 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.