Study Assessing PTI-428 Safety, Tolerability, and Pharmacokinetics in Subjects With Cystic Fibrosis


About this study

This trial will consist of three arms: Part A, Part B, and Part C. Part A has two groups. The first group will enroll adult subjects with cystic fibrosis (CF) into a single ascending dose (SAD) treatment group. The second group will enroll adult subjects with CF, including those on background treatment with ORKAMBI® and those not on a cystic fibrosis transmembrane conductance regulator (CFTR) modulator, into a multiple ascending dose (MAD) treatment group. Part B will enroll adult subjects with CF currently on stable ORKAMBI® background therapy for a minimum of 3 months into a Phase II treatment group consisting of two cohorts. Part C will enroll adult subjects with CF, including those on background treatment with KALYDECO® and those not on a CFTR modulator, into a Phase II treatment group consisting of three cohorts. Approximately 136 subjects will be enrolled.

Participation eligibility

Participant eligibility includes age, gender, type and stage of disease, and previous treatments or health concerns. Guidelines differ from study to study, and identify who can or cannot participate. There is no guarantee that every individual who qualifies and wants to participate in a trial will be enrolled. Contact the study team to discuss study eligibility and potential participation.

Inclusion Criteria:

  • Confirmed diagnosis of CF.
  • Forced expiratory volume in 1 second (FEV1) 40-90% predicted.
  • Non-smoker and non-tobacco user for a minimum of 30 days prior to screening and for the duration of the study.

Exclusion Criteria:

  • Participation in another clinical trial or treatment with an investigational agent within 30 days or 5 half-lives, whichever is longer, prior to Study Day 1.
  • History of cancer within the past five years (excluding cervical CIS with curative therapy for at least one year prior to screening and non-melanoma skin cancer).
  • History of organ transplantation.
  • Any sinopulmonary infection or CF exacerbation requiring a change or addition of medication (including antibiotics) within 1 month of Study Day 1 or any other clinically significant infection as determined by the investigator within 1 month of Day 1.
  • History of alcohol or drug abuse or dependence within 12 months of screening as determined by the Investigator.
  • Male and female of child-bearing potential, unless they are using highly effective methods of contraception during participation in the clinical study and for 4 weeks after termination from study.
  • Pregnant or nursing women.

Participating Mayo Clinic locations

Study statuses change often. Please contact the study team for the most up-to-date information regarding possible participation.

Mayo Clinic Location Status

Rochester, Minn.

Mayo Clinic principal investigator

Mark Wylam, M.D.

Closed for enrollment

More information


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Study Results Summary

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Supplemental Study Information

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