The antiviral drug candidate molnupiravir (yellow) is incorporated into the viral RNA, where it leads to mutations (purple) that ultimately prevent the virus from replicating.
Florian Kabinger, Christian Dienemann and Patrick Cramer @MPI-BPC

Molecular mechanisms of corona drug candidate Molnupiravir unraveled

The United States recently secured 1.7 million doses of a compound that could help to treat Covid-19 patients. In preliminary studies, Molnupiravir reduced the transmission of the SARS-CoV-2 coronavirus. Studies, including work by MBExC member Patrick Cramer at the MPI for Biophysical Chemistry and researchers at JMU Würzburg, showed why the drug has a rather weak effect on the virus. The antiviral agent incorporates RNA-like building blocks into the RNA genome of the virus. If this genetic material is further replicated, defective RNA copies are produced and the pathogen can no longer spread. Molnupiravir is currently being tested in clinical trials. (Nature Structural and Molecular Biology, August 11, 2021)

Link to the MPI-BPC press release