ACTA1 and idiopathic pulmonary fibrosis: We do note that in the few in vitro studies that do report IC50, that those values were lower – 144 nM for inhibition of α-SMA in IPF cells (Wollin et al., 2014) and a conference abstract that notes 73 nM for inhibition of PDGF-stimulated collagen gel contraction with NHLF (Wollin et al., 2016).