A Study in Healthy Men to Find the Best Formulation of BI 894416 and to Test How This is Taken up in the Body

Inclusion Criteria: * Healthy male subjects according to the assessment of the investigator, as 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 55 years (inclusive) at the time of signing informed consent * Body mass index (BMI) of 18.5 to 29.9 kg/m2 (inclusive) as measured at screening * Signed and dated written informed consent prior to admission to the study, in accordance with Good Clinical Practice (GCP) and local legislation * Subjects who are sexually active must use, with their partner, highly effective contraception from the time of administration of trial medication until 30 days after administration of trial medication. Adequate methods are: * Condoms plus use of hormonal contraception by the female partner that started at least 2 months prior to administration of trial medication (e.g., implants, injectables, combined oral or vaginal contraceptives, intrauterine device) or * Condoms plus surgical sterilization (vasectomy at least 1 year prior to enrolment) or * Condoms plus surgically sterilised partner (including hysterectomy) or * Condoms plus intrauterine device or * Condoms plus partner of non-childbearing potential (including homosexual men) Subjects are required to use condoms to prevent unintended exposure of the partner (both, male and female) to the study drug via seminal fluid. Male subjects should use a condom throughout the study and for 30 days after last Investigational Medicinal Product (IMP) administration. Alternatively, true abstinence is acceptable when it is in line with the subject's preferred and usual lifestyle. If a subject is usually not sexually active but becomes active, with their partner, they must comply with the contraceptive requirements detailed above Male subjects should not donate sperm for the duration of the study and for at least 30 days after last IMP administration Exclusion criteria: * Any finding in the medical examination (including Blood pressure (BP), Pulse rate (PR), Electrocardiogram (ECG), physical and neurological examination) deviating from normal and assessed 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 40 to 90 mmHg, or pulse rate outside the range of 40 to 100 bpm at screening and pre-dose of first period * Any laboratory value outside the reference range that the investigator considers to be of clinical relevance * Any evidence of a concomitant disease assessed as clinically relevant by the investigator * Gastrointestinal, hepatic, renal, respiratory, cardiovascular, metabolic, immunological or hormonal disorders * Cholecystectomy or other surgery of the gastrointestinal tract that could interfere with the pharmacokinetics of the trial medication (except appendectomy or simple hernia repair) * Diseases of the central nervous system (including but not limited to any kind of seizures or stroke), and other relevant neurological or psychiatric disorders * History of relevant orthostatic hypotension, fainting spells, or blackouts * Chronic or relevant acute infections * History of relevant allergy or hypersensitivity (including allergy to the trial medication or its excipients). Inactive hayfever is permitted. * Use of drugs within 30 days of planned administration of trial medication that might reasonably influence the results of the trial (including drugs that cause QT/QTc interval prolongation) * Intake of an investigational drug in another clinical trial within 90 days of planned first administration of investigational drug in the current trial, or concurrent participation in another clinical trial in which investigational drug is administered * Smoker (unless the subject quit smoking for at least 3 months prior to first planned administration of trial medication) as demonstrated by a positive urine cotinine test; this includes also the use of e-cigarettes and nicotine replacement products * Alcohol abuse (consumption of more than 21 units per week) or positive alcohol breath test * Drug abuse or positive drug screening * Blood donation of more than 100 mL within 30 days of planned administration of trial medication or intended blood donation during the trial * Intention to perform excessive physical activities within one week prior to the administration of trial medication or during the trial * Inability to comply with the dietary regimen of the trial site * A marked baseline prolongation of QT/QTc interval (such as QTc intervals that are repeatedly greater than 450 ms) or any other relevant ECG finding at screening and predose * A history of additional risk factors for Torsade de Pointes (such as heart failure, hypokalaemia, or family history of Long QT Syndrome) * Subject is assessed as unsuitable for inclusion by the investigator, for instance, because the subject is not considered able to understand and comply with study requirements, or has a condition that would not allow safe participation in the study * History of relevant neurological disorder affecting the peripheral or central nervous system (this includes but is not limited to: stroke, epilepsy, inflammatory or atrophic diseases affecting the nervous system, cluster headache or any cancer of the nervous system). Febrile seizures in childhood or adolescence, recovered carpal tunnel syndrome, recovered uncomplicated meningitis, recovered herpes zoster, tension headache, occasional benign tics (e.g. due to stress) or minor par- or dysesthesia (e.g. as a side effect of prior blood withdrawal) do not constitute a history of relevant neurological disorder. * History of immunological disease, except allergy not relevant to the trial (such as mild hay fever or dust mite allergy) and except asthma in childhood or adolescence * History of cancer (other than successfully treated basal cell carcinoma) * Liver enzymes (ALT, AST, GGT, AP) above upper limit of normal at the screening examination * Within 10 days prior to administration of trial medication, use of any drug that could reasonably inhibit platelet aggregation or coagulation (e.g., acetylsalicylic acid) * Male subjects with Woman of child bearing potential (WOCBP) partner who are unwilling to use male contraception (condom or sexual abstinence) from time point of first administration of trial medication until 30 days after the last administration of trial medication * Subjects with pregnant or lactating partners