This study is open to adults aged 18 and older or above legal age who have systemic sclerosis. People can participate if they have a specific subtype called diffuse cutaneous systemic sclerosis. People with another subtype called limited cutaneous systemic sclerosis can also participate if they are anti Scl-70 antibody positive. Systemic sclerosis is also called scleroderma.
The purpose of this study is to find out whether a medicine called Avenciguat (BI 685509) helps people with scleroderma who have symptoms due to lung fibrosis or vascular problems.
Participants are put into 2 groups by chance. One group takes Avenciguat (BI 685509) tablets 3 times a day and the other group takes placebo tablets 3 times a day. Placebo tablets look like BI 685509 tablets but do not contain any medicine. Participants take the tablets for at least 11 months. Afterwards, participants can continue to take the tablets until the last participant has completed the 11-months treatment period. This means that the time in the study and duration of treatment is different for each participant, depending on when they start the study. At the beginning of the study, participants visit the study site every 2 weeks. The time between the visits to the study site gets longer over the course of the study. After the 11-months treatment period, participants visit the study site every 3 months.
During the study, participants regularly do lung function tests. The results are compared between the 2 groups to see whether the treatment works. The participants also regularly fill in questionnaires about their scleroderma symptoms. The doctors regularly check participants' skin condition and general health and take note of any unwanted effects.