SHH and idiopathic interstitial pneumonia: Vismodegib: Vismodegib is the first approved small molecule inhibitor of the Shh signaling pathway and is initially indicated for the treatment of adults with basal cell carcinoma.[558] Clinical trials have been conducted to examine the possibility of orally used vismodegib in combination with PFD for the treatment of IPF, but further studies may be limited due to tolerability issues (NCT02648048).[559]