Inclusion Criteria:

1. ≥ 7 years of age.
2. Females of childbearing potential must be willing to use birth control (intrauterine device [IUD]; oral, transdermal or parenteral contraceptives; abstinence).

3. Diagnosis of CF based upon the following criteria:

   1. two clinical features consistent with CF; and
   2. either genotype with two identifiable mutations consistent with CF;
   3. or sweat chloride > 60 mEq/L by quantitative pilocarpine iontophoresis.
4. Clinically stable with no evidence of acute upper or lower respiratory tract infection.
5. PI determined by fecal elastase < 100 µg/g stool measured at the Screening Visit.
6. Able to take pancreatic enzyme supplementation in the form of capsules.
7. Able to perform the testing (e.g., stool collections) and inpatient stays required for this study, as judged by the Investigator.
8. Willing and able to provide informed consent or assent.
9. Baseline coefficient of fat absorption (CFA) ≤ 80%.

Exclusion Criteria:

1. < 7 years of age.
2. CFA > 80% at Baseline.
3. Pregnancy, breastfeeding or of childbearing potential and not willing to use birth control (IUD; oral, transdermal or parenteral contraceptives; abstinence) during the study.
4. History of fibrosing colonopathy.

5. History of liver transplant, lung transplant or significant surgical resection of the bowel.

   Note: Significant resection of the bowel is defined as any resection of the terminal ileum, or ileo-cecal valve. Patients who have had qualitative, long-term changes in nutritional status after any other bowel resection (e.g., increased, or new, need for supplementation compared to pre-op in order to maintain the same nutritional status) should also be excluded.

6. Any acute or chronic diarrheal illness unrelated to PI (e.g. infectious gastroenteritis, sprue, lactose intolerance, inflammatory bowel disease).
7. Unable to discontinue enteral tube feedings during the study.
8. Known hypersensitivity to food additives.
9. Inability to consume the PP diets, in the judgment of the Investigator.
10. Participation in an investigational study of a drug, biologic, or device not currently approved for marketing within 30 days prior to the Screening Visit.
11. ALT or AST level > 5x upper limit of normal (ULN), or total bilirubin level > 1.5x ULN at the Screening Visit or at Baseline (except for patients with Gilbert Syndrome).
12. Signs and/or symptoms of liver cirrhosis or portal hypertension (e.g., splenomegaly, ascites, esophageal varices), or documented liver disease unrelated to CF(‡).
13. Distal intestinal obstruction syndrome (DIOS) in the last six months prior to the Screening Visit.
14. Unable to discontinue the use of pancreatic enzymes.
15. Any condition that the Investigator believes would interfere with the intent of this study or would make participation not in the best interest of the patient.
16. Patient is unlikely to complete the study, as determined by the Investigator.

(‡) Eligible patients with ALT or AST level > 3x to 5x ULN at the Screening Visit or at Baseline will be tested for viral hepatitis. Other diagnostic testing may be performed at the discretion of the Investigator.