Riociguat in Scleroderma Associated Digital Ulcers

riociguat 0.5 mg, 1 mg, 1.5 mg, 2 mg and 2.5 mg administered TID; dose titration starting with 1.0 mg (planned up-titration every 2 weeks, with possibility of dose reduction for tolerability; 0.5 mg is the lowest dose and 2.5 mg is the highest dose to be administered)

Placebo 0.5 mg, 1 mg, 1.5 mg, 2 mg and 2.5 mg administered TID;