This clinical trial is focused on studying Cystic Fibrosis, a genetic condition that affects the lungs and digestive system. The study will evaluate the effectiveness and safety of three investigational treatments: Dirocaftor (also known as PTI-808), Posenacaftor (PTI-801), and Nesolicaftor (PTI-428). These treatments are being tested to see if they can help improve the health of individuals with cystic fibrosis by targeting specific genetic mutations associated with the disease.
The purpose of the study is to assess how well these treatments work over a period of 8 weeks. Participants will be randomly assigned to receive either the investigational treatments or a placebo. The study is designed to be double-blind, meaning neither the participants nor the researchers will know who is receiving the actual treatment or the placebo. This helps ensure that the results are not biased. The study will follow a crossover design, which means that participants will have the opportunity to receive both the investigational treatments and the placebo at different times during the study.
Throughout the study, participants will have regular check-ups to monitor their health and assess the effects of the treatments. These check-ups will include measurements of lung function, sweat chloride levels, and weight, as well as questionnaires about respiratory symptoms. The study aims to provide valuable information on the potential benefits of these treatments for people with cystic fibrosis, particularly those with rare genetic mutations. The total duration of the study is expected to be 16 weeks, with participants receiving treatment for 8 weeks and then switching to the other treatment option for another 8 weeks.



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