This protocol will enroll children aged 7 to 11 years old, suffering from Cystic Fibrosis and Pancreatic Insufficiency in order to demonstrate the safety of Ultrase MT20 as well as the efficacy of this product in the improvement of the fat absorption.

This study will include 3 phases: the screening phase, the washout phase and the treatment phase.

Screening Phase: this phase will last fifteen (15) days and all patients will take ULTRASE MT20 during this period. During the last 4 days, patents will be stabilized on a high fat diet and with Ultrase MT20.

Washout Phase: this phase will last 6 to 7 days. The patient will continue the high-fat diet but WILL REFRAIN from taking ULTRASE MT20 or any other enzymes. A 72-hour stool collection will be performed and all food consumed by the patient will be recorded to assess the Coefficient of Fat Absorption (CFA%) and the Coefficient of Nitrogen Absorption (CNA%).

Treatment Phase: this phase will last 7 to 11 days. The patient will continue the high-fat diet and will take the 'Stabilized Dose' of ULTRASE MT20 established during screening. Another 72-hour stool collection will be performed and all food consumed by the patient will be recorded to assess the Coefficient of Fat Absorption (CFA%) and the Coefficient of Nitrogen Absorption CNA%).

• Cystic Fibrosis
• Pancreatic Insufficiency

Inclusion Criteria:

1. Signature of an informed consent or assent form along with a parental form.
2. Patients must have a confirmed diagnosis of Cystic Fibrosis.
3. Patients must have Pancreatic Insufficiency and must require pancreatic enzyme supplementation.
4. Patients must be 7 to 11 years of age.
5. Patients must have an adequate nutritional status.
6. Patients must be on an optimal clinical dose of pancreatic enzymes prior to entry in the study, and must tolerate this medication in the opinion of the investigator.
7. Patients must be able to eat a high-fat diet.
8. Female patients should be premenarcheal. Otherwise, a female patient of childbearing potential (WOCBP) must not be pregnant and must have practiced an acceptable method of contraception for at least one month prior to the study entry.

Exclusion Criteria:

1. Patients with a known contraindication, sensitivity or hypersensitivity to ULTRASE or any porcine protein.
2. Patients with a known allergy to the FD&C Blue No. 2 dye indicator (stool marker).
3. Patients who use narcotics chronically and bowel stimulants and/or laxatives on a regular basis.
4. Patients with acute pancreatitis or acute exacerbation of chronic pancreatic disease.
5. Patients with an acute pulmonary infection.
6. Patients with a history of bowel resection.
7. Patients suffering from any dysmotility disorders.
8. Patients with chronic or severe abdominal pain.
9. Patients receiving enteral tube feeding and not willing to stop during the course of the study.
10. Patients with a history of or a current diagnosis of clinically significant portal hypertension.
11. Patients who have a condition known to increase fecal fat loss
12. Patients with a current diagnosis or a history of complete DIOS in the past six (6) months; or, patients who had two (2) or more episodes of DIOS in the past year.
13. Patients with poorly controlled diabetes according to the investigator's opinion
14. Female patients who are pregnant or lactating.
15. Patients who received an Investigational drug within 30 days prior to entry into the study.