TGM2 and cystinosis: The compound cysteamine hydrochloride (CH), a known TGM2 inhibitor, is already available in an FDA-approved topical formulation for the ocular manifestations of Cystinosis (Cystaran® Sigma-Tau Pharmaceuticals, Inc., Gaithersburg, MD, USA), which include corneal ulceration and secondary corneal scarring (Makuloluwa and Shams, 2018).