The main objectives are:
* To assess mass balance by determining the extent of recovery of total \[¹⁴C\]-radioactivity in urine and faeces after a single oral dose administration of BI 1815368 (C-14) (test treatment T) in healthy male trial participants.
* To investigate the absolute bioavailability of BI 1815368 using a single, concomitant intravenous micro-dose administration of BI 1815368 (C13) (reference treatment R).
* To provide plasma, urine, and faecal samples