This study looks at lung problems in people with cystic fibrosis (CF). CF is a disease that affects the lungs and makes breathing hard. Sometimes, these lung problems get worse and need special medicine called antibiotics, which are given through a tube in a vein (IV). The study compares two treatments: using one antibiotic called β-lactams, or using two antibiotics, tobramycin and β-lactams. Scientists want to know which treatment works best for improving lung health.

The study lasts for about 28 days. Participants must be at least 6 years old, have CF, and need IV antibiotics for 14 days. Pregnant people or those with certain health issues cannot join. The study checks if one or two antibiotics work better in helping people breathe easier.

• Study lasts for about 28 days with two visits.
• Ages 6 and up with cystic fibrosis can join.
• Must not be pregnant or have recent serious lung issues.