CETSA MS Profiling for a Comparative Assessment of FDA-Approved Antivirals Repurposed for COVID-19 Therapy Identifies TRIP13 as a Remdesivir Off-Target

SLAS Discov. 2021 Mar;26(3):336-344. doi: 10.1177/2472555220973597. Epub 2020 Nov 18.


The reuse of preexisting small molecules for a novel emerging disease threat is a rapid measure to discover unknown applications for previously validated therapies. A pertinent and recent example where such a strategy could be employed is in the fight against coronavirus disease 2019 (COVID-19). Therapies designed or discovered to target viral proteins also have off-target effects on the host proteome when employed in a complex physiological environment. This study aims to assess these host cell targets for a panel of FDA-approved antiviral compounds including remdesivir, using the cellular thermal shift assay (CETSA) coupled with mass spectrometry (CETSA MS) in noninfected cells. CETSA MS is a powerful method to delineate direct and indirect interactions between small molecules and protein targets in intact cells. Biologically active compounds can induce changes in thermal stability, in their primary binding partners, and in proteins that in turn interact with the direct targets. Such engagement of host targets by antiviral drugs may contribute to the clinical effect against the virus but can also constitute a liability. We present here a comparative study of CETSA molecular target engagement fingerprints of antiviral drugs to better understand the link between off-targets and efficacy.

Keywords: CETSA MS; COVID-19; TRIP13; antivirals; target engagement.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • ATPases Associated with Diverse Cellular Activities / metabolism*
  • Adenosine / analogs & derivatives
  • Adenosine Monophosphate / analogs & derivatives
  • Adenosine Monophosphate / pharmacology
  • Alanine / analogs & derivatives
  • Alanine / pharmacology
  • Antiviral Agents / pharmacology*
  • COVID-19 Drug Treatment
  • Cell Cycle Proteins / metabolism*
  • Drug Evaluation, Preclinical / methods*
  • Drug Repositioning
  • Furans / pharmacology
  • Hep G2 Cells
  • Humans
  • Mass Spectrometry
  • Proteomics / methods
  • Pyrroles / pharmacology
  • Triazines / pharmacology
  • United States
  • United States Food and Drug Administration


  • Antiviral Agents
  • Cell Cycle Proteins
  • Furans
  • Pyrroles
  • Triazines
  • GS-441524
  • remdesivir
  • Adenosine Monophosphate
  • ATPases Associated with Diverse Cellular Activities
  • TRIP13 protein, human
  • Adenosine
  • Alanine