Ironwood Pharmaceuticals Inc. initiated a phase I study in healthy volunteers with IW-6463, its oral central nervous system (CNS)-penetrant soluble guanylate cyclase (sGC) stimulator, aimed at the treatment of serious and orphan CNS disorders, potentially including vascular dementia and Alzheimer's disease (AD). Data from the study are expected in the second half of the year, positioning IW-6463 to follow several ongoing programs into midstage development, but not by Ironwood. Instead, the sGC stimulator portfolio is set to transition to spinout Cyclerion Therapeutics Inc., with separation of the companies on track to complete in the first half of the year.