Ribavirin is a nucleoside analog, which shows structural similarity to guanosine. But guanosine's 6‐membered ring is only hinted at by the amide group. As such, it is incorporated by viral RdRPs, but interrupts RNA polymerization. 224  It is an approved drug in most countries and used against a variety of viral infections. Although its efficacy against SARS‐CoV‐2 has not been determined in large clinical trials, ribavirin has shown some promise in the treatment of COVID‐19 patients. 225