BI-3031185

This study is open to adults with borderline personality disorder (BPD) and with attention deficit/ hyperactivity disorder (ADHD). The purpose of this study is to find out how a medicine called BI 3031185 is tolerated by people with BPD or ADHD.
Participants with BPD with ADHD are in separate cohorts. Participants from each cohort are put into 2 groups of equal size randomly, which means by chance. Group 1 takes a single dose of BI 3031185 and Group 2 takes placebo. After a 2-week break, Group 1 takes placebo and Group 2 takes a single dose of BI 3031185. Participants take BI 3031185 and placebo as tablets.
Participants are in the study for about 1 to 2 months. They visit the study site 6 times and have 3 phone or video call visits. For 2 of the visits, participants stay overnight at the study site for 2 nights. During all the visits, doctors check participants' health and take note of any unwanted effects.

The main objectives of this trial are to investigate safety, tolerability and pharmacokinetics (PK) of BI 3031185 in healthy male subjects following administration of multiple rising doses.