Phase 2 study of galunisertib plus neoadjuvant chemoradiotherapy for locally advanced rectal cancer

Transforming growth factor β (TGF-β) is an immunosuppressive cytokine that is upregulated in colorectal cancer. Galunisertib is a TGF-β type 1 receptor kinase inhibitor. A phase 2 study at two centers in Portland (OR) evaluated the combination of galunisertib plus neoadjuvant chemoradiotherapy for locally advanced rectal cancer. The complete response rate was 32%. The treatment was well tolerated and resulted in promising survival outcomes. The authors conclude that the combination of galunisertib and neoadjuvant chemoradiotherapy warrants further assessment in randomized trials.