These agents are contraindicated in patients with thyroid NETs (i.e., medullary thyroid carcinoma) or multiple endocrine neoplasia type 2 (MEN2) based on rodent studies suggesting that GLP-1RAs promote tumor growth via activation of GLP-1R on rodent thyroid C-cells (4, 5). The gene discussed is GLP1R; the disease is multiple endocrine neoplasia type 2.