The inhibition of Smad7 using antisense oligonucleotides decreased inflammation in an animal model of TNBS colitis [32] and improved the clinical activity of patients with CD [33] The orally administered antisense oligonucleotide of Smad7 (mongersen) showed a clinical efficacy in CD patients, although high doses induced bowel obstruction caused by TGFβ signaling promoting fibrosis [34]. Here, TGFB1 is linked to Cowden disease.