A Study in People With Systemic Sclerosis to Test Whether Avenciguat (BI 685509) Has an Effect on Lung Function and Other Systemic Sclerosis Symptoms

Inclusion Criteria:

1. Signed and dated written informed consent in accordance with International Councilon Harmonisation (ICH) - Good Clinical Practice (GCP) and local legislation prior toadmission to the trial.

2. Male or female patients aged ≥18 years at time of consent (or above legal age, e.g.United Kingdom (UK) ≥16 years).

3. Patients must fulfill the 2013 American College of Rheumatology/European Alliance ofAssociations for Rheumatology (ACR/EULAR) classification criteria for Systemicsclerosis (SSc).

4. Patients must be diagnosed with limited or with diffuse cutaneous SSc as defined byLeRoy et al. (R17 0149). Patients diagnosed with limited cutaneous SSc may beincluded if they are anti Scl-70 antibody positive.

5. Diffuse cutaneous SSc disease onset (defined by first non-RP symptom) in patientswith diffuse cutaneous SSc must be within 7 years of Visit 1. Limited cutaneous SSconset must be within 2 years of Visit 1.

6. Evidence of active disease, defined as having at least one of the following:

• New onset of SSc within the last 2 years of Visit 1 OR

• New skin involvement or worsening of two new body areas within 6 months ofVisit 1 (out of the possible 17 body areas defined by Modified Rodnan SkinScore (mRSS) assessment, documented in clinical files) OR

• New involvement or worsening of one new body area if either chest or abdomenwithin 6 months of Visit 1 OR

• Worsening of skin thickening (e.g. ≥2 mRSS points) within 6 months of Visit 1OR

• ≥1 tendon friction rub

7. Elevated biomarkers on Visit 1 (screening) defined as at least one of the following:

• C-reactive protein (CRP) ≥6 mg/L (≥0.6 mg/dL), OR

• Erythrocyte sedimentation rate (ESR) ≥28 mm/h, OR

• Krebs von den Lungen 6 (KL-6) ≥1000 U/mL If none of the three criteria are metor respective test results should not be available, the patient can be enteredif the modified Disease Activity Index (mDAI) is ≥ 2.5.

8. Evidence of significant vasculopathy, defined as:

• Active Digital ulcer (DU(s)) on Visit 1 OR

• Documented history of DU(s), OR

• Previous treatment of RP with prostacyclin analogues or ≥ 1 other medications,including calcium channel blockers, nitrates,, NO donors in any form, includingtopical; phosphodiesterase 5 (PDE5) inhibitors (e.g. sildenafil, tadalafil,vardenafil); nonspecific PDE5 inhibitors (theophylline, dipyridamole) OR

• RP with elevated CRP ≥6 mg/L

• If none of the four criteria above are met, the patient can be entered if thediagnosis of Interstitial lung disease (ILD) has been confirmed Furtherinclusion criteria apply.

Exclusion Criteria:

1. Any known form of pulmonary hypertension.

2. Pulmonary disease with FVC <50% of predicted. at screening.

3. Other autoimmune connective tissue diseases, except for fibromyalgia,scleroderma-associated myopathy and secondary Sjogren syndrome.

4. Diffusing capacity for carbon monoxide (DLCO) (haemoglobin corrected) <40% ofpredicted at screening.

5. Any history of scleroderma renal crisis within the last 6 months.

6. Estimated glomerular filtration rate (eGFR) <30 mL/min/1.73 m2 (Chronic KidneyDisease Epidemiology (CKD-EPI) formula) or on dialysis at screening.

7. Cirrhosis of any Child-Pugh class (A, B or C).

8. Cholestasis at present, or Alkaline phosphatase (ALP) > 4 x Upper limit of normal (ULN), or ALP > 2 x ULN and Gamma-glutamyl transferase (GGT) > 3 x ULN at Screening.

Further exclusion criteria apply.