Antibiotic Treatment Of Staphylococcus Aureus In Stable People With CF

• Status: Recruiting
• Trial end date: 2025-06-30
• Target enrollment: 0
• Participant gender: All

Summary

This is a randomized, double-blinded study that aims to assess the effect of an oral antibiotic called Cephalexin (150 mg/kg/day) compared to placebo in clinically stable children with cystic fibrosis who have grown a bacteria called MSSA (methicillin-susceptible Staphylococcus aureus) over the course of 2 weeks.

A sensitive technique called MBW (multiple breath washout) will be used to look at how well the participants lungs are functioning during the study and to see if the antibiotic improves function. The primary outcome of the study will be the relative change in the MBW measurement (LCI2.5) between day 0 and day 14 of study treatment.

• Phase: Phase 3
• Accepts Healthy Volunteers?: No

Details

• Lead Sponsor: University of British Columbia
• Collaborator: The Hospital for Sick Children
• Treatments: Cephalexin

Criteria

Inclusion Criteria:

1. Diagnosis of CF as evidenced by one or more clinical feature consistent with the CF phenotype or positive CF newborn screen AND one or more of the following criteria:

1. A documented sweat chloride ≥ 60 mEq/L by quantitative pilocarpine iontophoresis (QPIT)

2. A documented genotype with two disease-causing mutations in the CFTR gene

2. Age 3 years and over, up to 16th birthday.

3. Weight ≥ 10.0kg

4. No increase in lower respiratory tract symptoms from baseline for 28 days.

5. At least one episode of MSSA growth on airway culture in the past 24 months.

6. Successful MBW test occasion at the Screening Visit, per the assessment of the Site MBW Operator.

7. Informed consent by participant or parent/legal guardian with written assent where age-appropriate.

Randomization inclusion at each visit(applied after every Study Visit in the Phase 1)

1. Growth of isolated MSSA on bacterial airway culture from this Study Visit.

2. Acceptable MBW test at this Study Visit, per the assessment of the Site MBW Operator.

3. Participant willing to be randomised.

Exclusion Criteria:

1. Change of any respiratory medications within 28 days of enrollment (i.e. recent increase in pancreatic enzyme dosing, or similar, is not an exclusion).

2. Chronic infection (>=50% positive airway cultures over the previous 12 months) with any of the following: Pseudomonas aeruginosa, Burkholderia cepacia complex, Stenotrophomonas maltophilia or Achromobacter spp, MRSA or any non-tuberculous mycobacteria.

3. Chronic daily antibiotic use (oral, inhaled or intravenous; including azithromycin or cycling month inhaled antibiotics).

4. Systemic corticosteroid use for any indication within 28 days.

5. Allergic bronchopulmonary aspergillosis (ABPA) requiring corticosteroid therapy within 12 months.

6. Known allergy to cephalexin or other cephalosporins.

7. Previous organ transplantation.

8. Clinical findings that, in the opinion of the Site Investigator, would compromise the safety of the participant or the quality of the study data.

Randomisation exclusion(applied after every Study Visit in the Phase 1)

1. Increase in respiratory (upper or lower) symptoms from baseline in the previous 28 days.

2. Change of any respiratory medications within 28 days.

3. New diagnosis of allergic bronchopulmonary aspergillosis (ABPA) since previous encounter.

4. New use of chronic daily antibiotics since previous encounter.

5. Clinical findings that, in the opinion of the Site Investigator, would compromise the safety of the participant or the quality of the study data.