The investigators believe that activation of sGC could play a role in migraine pathophysiology and propose that stimulation with riociguat causes cranial arterial dilation alongside headache in healthy volunteers.~Twelve healthy volunteers participate at a screening visit, and if eligible, on two separate study days, where participants, in a randomized cross-over fashion, will ingest either riociguat (active comparator arm) or placebo (placebo comparator arm), serving as their own controls. On the two separate study days the investigators will measure change in diameter of superficial temporal artery and middle cerebral artery blood flow velocity and register possible headache until 4 hours after intake of riociguat or placebo. At home participants are expected to fill out a headache diary until 12 hours from intake of riociguat or placebo.~Leading up to the main study described above, the investigators will conduct a pilot dose-finding study (experimental arm) of increasing doses of riociguat, 2,5mg and 5mg respectively, on two separate study days in 5 healthy volunteers, to ensure an appropriate dose is applied in the main study.
This double-blind, randomized, placebo-controlled cross-over clinical trial aims to investigate the effects of riocigaut on cerebral arteries and headache inducing properties in healthy volunteers.