In searching for treatments for Covid-19, researchers discovered that a cancer drug called Aplidin (aka: Plitidepsin), originally isolated from Mediterranean sea squirts, was up to 27.5 times more effective at killing the virus in cell cultures than the FDA-approved drug Remdesivir! Importantly, it was also shown to be effective at preventing the virus from replicating in mice.
KM White, R Rosales, S Yildiz, T Kehrer, L Miorin, E Moreno, S Jangra, MB Uccellini, R Rathnasinghe, L Coughlan, C Martinez-Romero, J Batra, A Rojc, M Bouhaddou, JM Fabius, K Obernier, M Dejosez, MJ Guillén, A Losada, P Avilés, M Schotsaert, T Zwaka, M Vignuzzi, KM Shokat, NJ Krogan, A García-Sastre. Plitidepsin has potent preclinical efficacy against SARS-CoV-2 by targeting the host protein eEF1A. Science. eabf4058, 2021.