Cystic fibrosis (CF) is a disease caused by a mutation in the gene that makes the cystic fibrosis transmembrane regulator protein. As a result mucus stagnation, obstruction and plugging take place in the respiratory and gastrointestinal tract, the biliary and pancreatic duct, and in the reproductive system. The objective of this study is to determine the safety and tolerability of 3 days of daily dosing of OligoG CF-5/20 versus placebo in healthy volunteers.

Inclusion Criteria:

• Healthy, male subjects aged 18 to 65 years inclusive
• Normal pulmonary function; i.e. FEV1 ≥ 80% of predicted (for age, sex, height and race) and FEV1/FVC ratio ≥ 0.7
• Subject's pre -study physical examination, vital signs and electrocardiogram (ECG) are normal or do not show any clinically significant abnormalities as determined by the investigator
• Subject's pre - study laboratory screen are normal or, if outside of the laboratory reference range, not considered clinically significant

Exclusion Criteria:

• History of any clinically relevant chronic respiratory disorder, including asthma
• Current smoker or smoked within the last 12 months
• History of significant drug or alcohol abuse (defined by the investigator). Subjects with a positive screen for alcohol or drugs of abuse at screening/admission will be excluded from participation in the study.
• Subject who has inhaled any drug in the last 30 days prior to Day 1
• Subject who has received one or more days of systemic pharmacological treatment in the 14 days immediately prior to Day 1
• Participation in a New Chemical Entity clinical study within the previous 16 weeks or a marketed drug clinical study within the previous 12 weeks
• Subjects with a clinically relevant history of significant hepatic, renal, endocrine, cardiac, nervous, psychiatric, gastrointestinal, pulmonary, haematological or metabolic disorder