<br>        Inclusion Criteria:<br><br>          -  • Healthy male and female subjects, aged 25-45 years. Women will be considered for<br>             inclusion if they are not pregnant, as confirmed by pregnancy test and not nursing.<br><br>        Females of childbearing potential need to use a highly effective method of contraception<br>        during the entire study (vasectomised partner, sexual abstinence - the lifestyle of the<br>        female should be such that there is complete abstinence from intercourse from two weeks<br>        prior to the first visit until at least 72 hours after the last visit -, implants,<br>        injectables, combined oral contraceptives, hormonal IUDs (intrauterine device) or<br>        double-barrier methods, i.e. any double combination of IUD, condom with spermicidal gel,<br>        diaphragm, sponge, and cervical cap).<br><br>          -  Body weight = 50 kg and BMI (body mass index) within the range 19-32 kg/m²<br><br>          -  Smokers need to consume at least ten cigarettes per day and need to have at least ten<br>             packyear<br><br>          -  Non-smokers need to be non-smoking since at least a year with a smoking history of no<br>             more than 1 packyear.<br><br>          -  FEV1 (forced expiratory volume at one second)=80% predicted and FEV1/FVC (forced<br>             expiratory vital capacity) =70%<br><br>        Exclusion Criteria:<br><br>          -  • History of an acute infection four weeks prior to the informed consent visit.<br><br>               -  Regular intake of medication.<br><br>               -  Past or present disease, which as judged by the investigator, may affect the<br>                  outcome of this study. These diseases include, but are not limited to,<br>                  cardiovascular disease, malignancy, hepatic disease, renal disease, hematological<br>                  disease, neurological disease, endocrine disease or pulmonary disease (including<br>                  but not confined to chronic bronchitis, emphysema, tuberculosis, bronchiectasis<br>                  or cystic fibrosis).<br><br>               -  Participation in another clinical trial 30 days prior to enrollment.<br>