A Study to Test Different Doses of BI 1569912 in People With Depression

Inclusion criteria * Male and female participants, 18 to 65 years of age, both inclusively at the time of consent * Signed and dated written informed consent in accordance with International Council for Harmonisation-Good Clinical Practice (ICH-GCP) and local legislation prior to admission to the trial * Women of childbearing potential (WOCBP) must be ready and able to use a highly effective method of birth control per ICH M3 (R2) that results in a low failure rate of less than 1% per year when used consistently and correctly plus one additional barrier method. A list of contraception methods meeting these criteria and instructions on the duration of use is provided in the participant information * Established diagnosis of Major depressive disorder (MDD), single episode or recurrent, as confirmed at the time of screening by the Mini-International Neuropsychiatric Interview (MINI) with a duration of the current depressive episode ≥8 weeks AND ≤24 months at the time of randomisation * Hamilton Depression Rating Scale-17 (HDRS-17) - Severity scale score ≥20 * Clinical Global Impression- Severity Scale (CGI-S) score ≥4 Exclusion criteria: * Per Mini International Neuropsychiatric Interview (MINI), have ever met diagnostic criteria for schizophrenia, schizoaffective disorder, schizophreniform disorder, bipolar disorder, or delusional disorder * Diagnosis with antisocial, paranoid, schizoid or schizotypal personality disorder, or MDD with psychotic features as per Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) criteria, at the time of screening visit. Any other personality disorder at screening visit that significantly affects current psychiatric status and likely to impact trial participation, as per the judgement of investigator * Diagnosis of any other mental disorder that was the primary focus of treatment within 6 months prior to screening (as per clinical discretion of the investigator) * Treatment failure to 2 or more antidepressants in the current episode, defined as less than 50% response to treatments administered at an adequate dose and duration as evaluated by the Antidepressant treatment response questionnaire (ATRQ) * History or presence (upon clinical examination) of seizure disorders or an increased risk of seizures (first degree relative with epilepsy), stroke, brain tumour, or any other major neurological illness that could impact participation in the trial * A current or recent history of clinically significant suicidal ideation with intent within the past 3 months, corresponding to a score of 4 or 5 for ideation on the Columbia-Suicide Severity Rating Scale (C-SSRS) or a suicidal attempt within the past year, as indicated by the C-SSRS at screening visit * Participants with a body mass index (weight \[kg\]/height \[m\]²) lower than 18 kg/m² or greater than 40 kg/m2 at screening * Diagnosis of a moderate to severe substance related disorder as defined by DSM-5 criteria within 6 months prior to screening visit (with exception of caffeine and tobacco) Further exclusion criteria apply.