A Study in Healthy Men to Test How Different Doses of BI 474121 Are Taken up and How They Influence the Amount of a Molecular Messenger (cGMP) in the Spinal Fluid

Placebo matching to 10 mg BI 474121 administered as uncoated tablets with 240 milliliter of water after subjects fasted overnight for at least 10 hours. This arm was part of Part 1: randomised, placebo-controlled, single-blind.

2.5 mg BI 474121 administered as uncoated tablets (1 x 2.5 mg) with 240 milliliter of water after subjects fasted overnight for at least 10 hours. This arm was part of Part 3 of the study: randomised, open-label.

10 mg BI 474121 administered as uncoated tablets (1 x 10 mg) with 240 milliliter of water after subjects fasted overnight for at least 10 hours. This arm was part of Part 3 of the study: randomised, open-label.

20 mg BI 474121 administered as uncoated tablets (2 x 10 mg) with 240 milliliter of water after subjects fasted overnight for at least 10 hours. This arm was part of Part 1 of the study: randomised, placebo-controlled, single-blind.

40 mg BI 474121 administered as uncoated tablets (4 x 10 mg) with 240 milliliter of water after subjects fasted overnight for at least 10 hours. This arm was part of Part 2 of the study: non-randomised, open-label.