Covidcil-19 (compound C5) avidly binds to the revised attenuator hairpin structure of the SARS-CoV-2 frameshifting element (FSE) with a Kd of 11 nM. Covidcil-19 stabilizes the hairpin’s folded state and impairs frameshifting in cells. Covidcil-19 reduces frameshifting efficiency of the SARS-CoV-2 FSE and does not affect SARS-CoV-2 FSE RNA levels. Covidcil-19 inhibits a process essential for SARS-CoV-2 viral propagation[1].