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

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.

Eligibility Criteria

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.

Study Contact

Larry Scott, CCRP, LPN 913-588-4020 lscott2@kumc.edu

Estimated Completion Date

Friday, December 1, 2017

ClinicalTrials.gov #

NCT02718495
04/27/2017