The invention provides rationally designed multi-targeting therapeutic agents for myotonic dystrophy type 1 (DM1), an incurable neuromuscular disease that originates in an abnormal expansion of CTG repeats (CTGexp) in the DMPK gene. The rationally designed small molecules target the DM1 pathobiology in three distinct ways: (1) binding the expanded trinucleotide repeat, CTGexp, and inhibiting its transcription to the toxic CUGexp RNA, (2) binding the CUGexp RNA and releasing sequestered muscleblind-like protein (MBNL1), and (3) cleaving the toxic CUGexp in an RNase-like manner. Importantly, the compounds can reduce the levels of CUGexp in DM1 model cells and reverse two separate CUGexp-induced phenotypes of DM1.
