['cystic fibrosis']
['inhaled mannitol', 'placebo comparator: arm b - control']

        Inclusion Criteria:

          1. Have given written informed consent to participate in this trial in accordance with
             local regulations;

          2. Have a confirmed diagnosis of cystic fibrosis (positive sweat chloride value ≥ 60
             mEq/L) and/or genotype with two identifiable mutations consistent with CF, accompanied
             by one or more clinical features consistent with the CF phenotype);

          3. Be aged at least 18 years old;

          4. Have FEV1 > 40 % and < 90% predicted (using NHanes III [1]);

          5. Be able to perform all the techniques necessary to measure lung function;

          6. Be adherent with maintenance therapies (antibiotics and or rhDNase), if used, for at
             least 80% of the time in the two weeks prior to visit 1 and

          7. If rhDNase and/or maintenance antibiotic are being used treatment must have been
             established at least 1 month prior to screening (Visit 0). The subject should remain
             on the rhDNase and / or maintenance antibiotics for the duration of the trial. The
             subject should not commence treatment with rhDNase or maintenance antibiotics during
             the trial

        Exclusion Criteria:

          1. Be investigators, site personnel directly affiliated with this trial, or their
             immediate families. Immediate family is defined as a spouse, parent, child or sibling,
             whether biologically or legally adopted;

          2. Be considered "terminally ill" or eligible for lung transplantation;

          3. Have had a lung transplant;

          4. Be using maintenance nebulized hypertonic saline in the 2 weeks prior to visit 1;

          5. Have had a significant episode of hemoptysis (> 60 mL) in the three months prior to
             Visit 0;

          6. Have had a myocardial infarction in the three months prior to Visit 0;

          7. Have had a cerebral vascular accident in the three months prior to Visit 0;

          8. Have had major ocular surgery in the three months prior to Visit 0;

          9. Have had major abdominal, chest or brain surgery in the three months prior to Visit 0;

         10. Have a known cerebral, aortic or abdominal aneurysm;

         11. Be breast feeding or pregnant, or plan to become pregnant while in the trial;

         12. Be using an unreliable form of contraception (female subjects at risk of pregnancy
             only);

         13. Be participating in another investigative drug trial, parallel to, or within 4 weeks
             of screening (Visit 0);

         14. Have a known allergy to mannitol;

         15. Be using non-selective oral beta blockers;

         16. Have uncontrolled hypertension -i.e. systolic BP > 190 and / or diastolic BP > 100;

         17. Have a condition or be in a situation which in the Investigator's opinion may put the
             subject at significant risk, may confound results or may interfere significantly with
             the subject's participation in the trial;or

         18. Have a failed or incomplete MTT at trial entry (as evaluated in Section 8.1.1.1).

         19. The subject must not commence treatment with rhDNase or maintenance antibiotics during
             the trial.
      