CAYSTON did not negatively affect the lung microbiology profile

Resistance to CAYSTON was not increased

  • No changes in susceptibility of Pseudomonas aeruginosa were observed following 28 days of treatment in the Phase 3 placebo-controlled studies.

In the follow-on study of up to 18 months, cross-resistance did not increase

  • No cross-resistance to other classes of antibiotics, including aminoglycosides, quinolones, and beta-lactams, was observed following a 28-day course of CAYSTON in the Phase 3 placebo-controlled trials or in an open-label follow-on trial of up to nine 28-day courses of 75 mg CAYSTON 3 times a day.

No trends in the treatment-emergent isolation of other bacterial respiratory pathogens were observed in clinical trials

  • Burkholderia cepacia, Stenotrophomonas maltophilia, Achromobacter xylosoxidans, and Staphylococcus aureus were not observed in clinical trials. There was a slight increase in the isolation of Candida spp. following up to nine 28-day courses of CAYSTON therapy.