The primary objective of this trial is to investigate the safety and tolerability of BI 456906 in healthy subjects following single rising doses.

The secondary objective is the exploration of the pharmacokinetics including dose proportionality, and pharmacodynamics (PD) of BI 456906 after single dosing

Inclusion criteria

• Healthy male according to the assessment of the Investigator, based on a complete medical history including a physical examination, vital signs (Blood Pressure (BP), Pulse Rate (PR)), 12-lead Electrocardiogram (ECG), and clinical laboratory tests
• Age of 18 to 45 years (incl.)
• Body Mass Index (BMI) of 20.0 to 29.9 kg/m2 (incl.)
• Signed and dated written informed consent prior to admission to the study in accordance with Good Clinical Practice (GCP) and local legislation

Exclusion criteria

• Any finding in the medical examination (including Blood Pressure (BP), Pulse Rate (PR) or Electrocardiogram (ECG)) is deviating from normal and judged as clinically relevant by the investigator
• Repeated measurement of systolic blood pressure outside the range of 90 to 140 mmHg, diastolic blood pressure outside the range of 50 to 90 mmHg, or pulse rate outside the range of 50 to 90 bpm
• Any laboratory value outside the reference range that the investigator considers to be of clinical relevance
• Gastrointestinal, hepatic, renal, respiratory, cardiovascular, metabolic, immunological or hormonal disorders
• Diseases of the central nervous system (including but not limited to any kind of seizures or stroke), and other relevant neurological or psychiatric disorders
• Use of drugs within 30 days prior to administration of trial medication if that might reasonably influence the results of the trial (incl. QT/QTc interval prolongation)
• Further exclusion criteria apply