Please select the eligibility criteria that correspond to the clinical trial below.
Title: Single Center, Double-blind, Randomized, Placebo-controlled, Two-period/Two-treatment Crossover Study Investigating the Effect of Miglustat on the Nasal Potential Difference in Patients With Cystic Fibrosis Homozygous for the F508del Mutation
Brief Summary: Single Center, Double-Blind, Randomized, Placebo-Controlled, Two-Period/Two-Treatment Crossover Study Investigating the Effect of Miglustat on the Nasal Potential Difference in Patients With Cystic Fibrosis Homozygous for the F508del Mutation


Options:
A: Inclusion Criteria:

* Aged 12 years and older
* Male or female Non-pregnant women who are to remain non-pregnant for 3 months after the end of the study. Women of childbearing potential must use a reliable method of contraception. Reliable methods of contraception for female patients include the following:
* barrier type devices (e.g., female condom, diaphragm and contraceptive sponge) used ONLY in combination with a spermicide
* intrauterine devices
* oral contraceptive agent
* Depo-Provera™ (medroxyprogesterone acetate)
* levonorgestrel implants Abstention, the rhythm method or contraception by the partner alone are NOT reliable methods of contraception. A woman is considered to have child-bearing potential unless she meets at least one of the following criteria:
* 6 weeks post-surgical bilateral salpingo-oophorectomy or hysterectomy
* Premature ovarian failure confirmed by a specialist gynecologist
* Age \> 50 years and not treated with any kind of HRT for at least 2 years prior to screening, and with amenorrhea for at least 24 consecutive months prior to screening and a serum FSH level of \> 40 IU/L at screening.
* Age \> 55 years and treated with HRT prior to screening with an appropriate medical documentation of spontaneous amenorrhea for at least 24 months. For female patients in the pediatric age range, a reliable method of contraception must be considered, if appropriate.

  * Male patients accepting for the duration of the study and for 3 months thereafter to use a condom and not to procreate a child (not in case of azoospermia)
  * Cystic fibrosis patients homozygous for the F508del mutation as confirmed by genetic test
  * Signed informed consent prior to any study-mandated procedure

Exclusion Criteria:

* Any condition prohibiting the correct measurement of the NPD such as upper respiratory tract infection
* Acute upper respiratory tract or pulmonary exacerbation requiring antibiotic intervention within 2 weeks of screening
* Severe renal impairment (creatinine clearance \< 30 mL/min as per Cockroft and Gault)
* Female patients of childbearing potential who will not undergo a pregnancy test prior to enrollment into the study
* History of significant lactose intolerance
* History of neuropathy
* Presence of clinically significant diarrhea (\> 3 liquid stools per day for \> 7 days) without definable cause within 1 month prior to screening
* Any known factor or disease that might interfere with treatment compliance, study conduct or interpretation of the results such as drug or alcohol dependence or psychiatric disease
* FEV1 \< 25% of predicted normal
* Oxygen saturation at rest \< 88%
* Active or passive smoking as measured using the Smokelyzer®
* Hypersensitivity to miglustat or any excipients
* Planned treatment or treatment with another investigationaldrug or therapy (e.g., gene therapy) within 1 month prior to randomization
* Breast-feeding, pregnant women or women who plan to become pregnant during the course of the study.
B: Inclusion Criteria:

Subjects entering the Treatment Cohort must meet both of the following criteria:

* Completed study visits up to Week 24 of Study 109 or Week 26 of Study 011B and did not permanently discontinue treatment
* Willing to remain on a stable CF medication through the Safety Follow-up Visit.

Subjects entering the Observational Cohort must meet 1 of the following criteria:

* Completed 24 weeks of study drug treatment in Study 109 or completed 24 weeks of study drug treatment and the Week 26 Safety Follow up in Study 011B.
* Received at least 4 weeks of study drug and completed visits up to Week 24 of Study 109 or Week 26 of Study 011B.

Exclusion Criteria (Treatment Cohort Only):

* History of any comorbidity or laboratory abnormality that, in the opinion of the investigator, might confound the results of the study or pose an additional risk in administering study drug to the subject (e.g., cirrhosis with portal hypertension).
* Pregnant and nursing females.
* Sexually active subjects of reproductive potential who are not willing to follow the contraception requirements.
* History of drug intolerance in the prior study that would pose an additional risk to the subject in the opinion of investigator
* History of poor compliance with study drug and/or procedure in the previous study as deemed by the investigator.
* Participation in an investigational drug trial (including studies investigating lumacaftor and/or ivacaftor).
C: Key Inclusion Criteria:

* Participants will be 1 to less than 2 years of age on day 1 of the relevant part of the study
* Homozygous for F508del (F/F)

Key Exclusion Criteria:

* Any clinically significant laboratory abnormalities at the screening visit that would interfere with the study assessments or pose an undue risk for the participants
* Solid organ or hematological transplantation

Other protocol defined Inclusion/Exclusion criteria may apply.
D: PROTOCOL ENTRY CRITERIA:

* Mild cystic fibrosis
* Not pregnant or nursing Negative pregnancy test

Answer: A