Validating Enterovirus D68-2A pro as an Antiviral Drug Target and the Discovery of Telaprevir as a Potent D68-2A pro Inhibitor

A 2014 EV-D68 outbreak in the United States has been linked to the development of acute flaccid myelitis in children. Unfortunately, no treatment options against EV-D68 are currently available, and the development of effective therapeutics is urgently needed. Here, we characterize and validate a new EV-D68 drug target, the 2A pro , and identify telaprevir—an FDA-approved drug used to treat hepatitis C virus (HCV) infections—as a potent antiviral with a novel mechanism of action toward 2A pro . 2A pro functions as a viral protease that cleaves a peptide sequence corresponding to the VP1-2A polyprotein junction. The binding of telaprevir potently inhibits its enzymatic activity, and using drug resistance selection, we show that the potent antiviral activity of telaprevir was due to 2A pro inhibition. This is the first inhibitor to selectively target the 2A pro from EV-D68 and can be used as a starting point for the development of therapeutics with selective activity against EV-D68.