Ritonavir does not inhibit calpain in vitro.

@article{Cuerrier2005RitonavirDN,
  title={Ritonavir does not inhibit calpain in vitro.},
  author={Dominic Cuerrier and Zilin Nie and Andrew D Badley and Peter L Davies},
  journal={Biochemical and biophysical research communications},
  year={2005},
  volume={327 1},
  pages={208-11}
}
Ritonavir, an inhibitor of HIV-1 protease, has been reported to also inhibit the Ca2+-dependent cysteine protease, calpain. We have investigated these claims with an in vitro study of the effect of ritonavir on the m-calpain and mu-calpain isoforms. Ritonavir failed to block either autolytic or hydrolytic calpain activity, but remained fully capable of… CONTINUE READING