Pharmacokinetics of Single Doses of BILR 355 BS Given With Ritonavir in Healthy Male Volunteers

Inclusion Criteria: * All participants in the study should be healthy males * Age range from 21 to 50 years * Body mass index (BMI) be within 18.5 to 29.9 kg/m2 * In accordance with Good Clinical Practice and the local legislation all volunteers will have given their written informed consent prior to admission to the study Exclusion Criteria: * Any finding of the medical examination (including blood pressure, pulse rate and ECG) deviating from normal and of clinical relevance * Gastrointestinal, hepatic, renal, respiratory, cardiovascular, metabolic, immunological or hormonal disorders * Diseases of the central nervous system (such as epilepsy) or psychiatric disorders or neurological disorders * History of orthostatic hypotension, fainting spells or blackouts * Chronic or relevant acute infections * History of allergy/hypersensitivity (including drug allergy) which is deemed relevant to the trial as judged by the investigator * Intake of drugs with a long half-life (\> 24 hours) within at least one month or less than ten half-lives of the respective drug before enrolment in the study or during the study * Use of any drugs which might influence the results of the trial up to 7 days prior to enrolment in the study or during the study * Participation in another trial with an investigational drug (≤ two months prior to administration or during the trial) * Smoker (\> 10 cigarettes or \> 3 cigars of \> 3 pipes/day) * Inability to refrain from smoking on trial days * Alcohol abuse (\> 60 g/day) * Drug abuse * Blood donation (≥ 100 mL within four weeks prior to administration or during the trial) * Any laboratory value outside the clinically accepted reference range * Excessive physical activities within the last week before the trial or during the trial Following exclusion criteria are of special interest for this study: * Erythema, exanthema and comparable skin alterations