pharmacodynamic effects, safety and tolerability of cilobradine, compared to metoprolol succinate and placebo in healthy volunteers

Conditions: Healthy

Summary: pharmacodynamic effects on heart rate (hr) at rest and during exercise and on flicker fusion frequency (fff), fff method evaluation safety, tolerability and pharmacokinetics of cilobradine


Eligibility criteria:
inclusion criteria: * all participants in the study should be healthy males and females. volunteers will * be 21 to 55 years of age * have a body mass index (bmi) of 19.9 to 29.9 kg/m2 and * have a resting heart rate (hr) (after 10 min. in the supine position) of more than 55 beats per minute (bpm) * only post-menopausal females, or those who had had a hysterectomy, could participate. all females had to have a negative pregnancy test * in accordance with good clinical practice (gcp) and the local legislation all volunteers had to give their written informed consent prior to admission to the study exclusion criteria: * any finding of the medical examination (including bp, hr 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 or psychiatric disorders or neurological disorders * history of relevant 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 ten half-lives of the respective drug before enrolment in the study * use of any drugs which might influence the results of the trial within two weeks prior to administration or during the trial * 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) * excessive physical activities (within the last week before the study) * any laboratory value outside the reference range of clinical relevance not necessarily clinically relevant abnormalities, but specific exclusion criteria for the drugs under study or for the study: * consumption of more than 2 cups of coffee or black tea, or cola drinks, per day during the last 6 weeks. however, subjects may participate if abstinence from the before mentioned beverages is well tolerated during an interval of at least 2 weeks between screening and first treatment * ecg: pq interval \> 210 ms * hr at rest \< 55 bpm * systolic bp \< 115 mmhg * colour vision test abnormal. however, subjects may participate if they are able to perform the flicker fusion test without difficulty * psoriasis (own medical history or relative) * relevant ophthalmological disease * history of asthma or obstructive pulmonary disease * history (including childhood) of traumatic injury to the head or brain * history (including childhood) of reduced seizure threshold * the following subjects will not be allowed to participate in the study * any subject involved in professional transportation of human subjects * any subject involved in operating dangerous machinery