Open-label, Randomised, 4 Parallel-group, Phase I Clinical Trial to Investigate BI 456906 Occupancy of Glucagon Receptors in Liver and Glucagon-like Peptide 1 Receptors in Pancreas in Comparison With Semaglutide After Administration of Radiolabeled Tracer in Male and Female Subjects With Obesity Using PET and MRI

This study is open to adults with obesity. People with a body mass index (BMI) in the range from 30 to 40 kg/m2 and a body weight of 70 to 150 kg can participate in the study. The purpose of this study is to find out whether treatment with a medicine called BI 456906 changes the occupancy of receptors in the liver and in the pancreas. These receptors are involved in appetite and weight regulation. To measure the occupancy of these receptors, doctors use injectable tracers. Doctors visualise the binding of the tracers to these receptors with imaging methods.

Participants are put into 4 groups randomly, which means by chance. 2 groups get BI 456906 and 2 groups get semaglutide. Semaglutide is an approved medicine for body weight reduction. For 17 weeks, participants get injections under the skin. They either get BI 456906 twice a week or semaglutide once a week. The injected doses increase in small steps. Before and after 17 weeks of treatment, the receptor occupancy is determined.

Participants are in the study for up to 6 months. At the beginning and at the end of the treatment participants stay at the study site with an overnight stay. At the beginning, the study staff trains participants how to inject the study treatment at home. Participants who get BI 456906 visit the study site 18 times and have 19 visits at home. Participants who get semaglutide visit the study site 15 times and have 6 home visits. The doctors also regularly check participants' health and take note of any unwanted effects.