Avenciguat: a novel soluble guanylate cyclase activator that affects multiple cell types to inhibit IFN-1 signalling and fibrosis.

Abstract

The soluble guanylate cyclase (sGC) stimulator riociguat is approved for the treatment of pulmonary arterial hypertension and may have antifibrotic effects. However, in fibrotic tissues, oxidative stress and hypoxia can render sGC insensitive to sGC stimulators. sGC activators overcome this limitation. Here, we characterize the novel sGC activator, avenciguat, in preclinical models of SSc. Human microvascular endothelial cells-dermal (HMVEC-d) cultured in hypoxic conditions and activated human platelet-rich plasma were incubated with varying doses of avenciguat, and the levels of TGF-β2 and human CXC chemokine family ligand 4 (CXCL4) were measured, respectively. Treatment with avenciguat was analysed in mice with bleomycin-induced dermal and pulmonary fibrosis. Avenciguat reduced hypoxia-induced synthesis of TGF-β2 by HMVEC-d and inhibited CXCL4 release by platelets. Moreover, avenciguat demonstrated antifibrotic effects on bleomycin-induced dermal and pulmonary fibrosis. RNA sequencing of affected skin uncovered a unique profile distinguishing avenciguat from riociguat. Avenciguat treatment resulted in deeper regulation of IFN-1 signalling and genes associated with immune response vs riociguat treatment. In preclinical studies, avenciguat shows the potential to influence vascular, fibrotic and immune-related processes in murine models of SSc. These studies suggest that it may offer therapeutic benefit across multiple aspects of SSc pathophysiology and support the rationale for further investigation in a Phase II clinical trial (VITALISScE™; NCT05559580) of avenciguat in SSc.