RT Journal Article SR Electronic T1 Preclinical and randomized phase I studies of plitidepsin in adults hospitalized with COVID-19 JF Life Science Alliance JO Life Sci. Alliance FD Life Science Alliance LLC SP e202101200 DO 10.26508/lsa.202101200 VO 5 IS 4 A1 Varona, Jose F A1 Landete, Pedro A1 Lopez-Martin, Jose A A1 Estrada, Vicente A1 Paredes, Roger A1 Guisado-Vasco, Pablo A1 Fernandez de Orueta, Lucia A1 Torralba, Miguel A1 Fortun, Jesus A1 Vates, Roberto A1 Barberan, Jose A1 Clotet, Bonaventura A1 Ancochea, Julio A1 Carnevali, Daniel A1 Cabello, Noemi A1 Porras, Lourdes A1 Gijon, Paloma A1 Monereo, Alfonso A1 Abad, Daniel A1 Zuñiga, Sonia A1 Sola, Isabel A1 Rodon, Jordi A1 Vergara-Alert, Julia A1 Izquierdo-Useros, Nuria A1 Fudio, Salvador A1 Pontes, Maria Jose A1 de Rivas, Beatriz A1 Giron de Velasco, Patricia A1 Nieto, Antonio A1 Gomez, Javier A1 Aviles, Pablo A1 Lubomirov, Rubin A1 Belgrano, Alvaro A1 Sopesen, Belen A1 White, Kris M A1 Rosales, Romel A1 Yildiz, Soner A1 Reuschl, Ann-Kathrin A1 Thorne, Lucy G A1 Jolly, Clare A1 Towers, Greg J A1 Zuliani-Alvarez, Lorena A1 Bouhaddou, Mehdi A1 Obernier, Kirsten A1 McGovern, Briana L A1 Rodriguez, M Luis A1 Enjuanes, Luis A1 Fernandez-Sousa, Jose M A1 Krogan, Nevan J A1 Jimeno, Jose M A1 Garcia-Sastre, Adolfo YR 2022 UL http://www.life-science-alliance.org/content/5/4/e202101200.abstract AB Plitidepsin, a marine-derived cyclic-peptide, inhibits SARS-CoV-2 replication at nanomolar concentrations by targeting the host protein eukaryotic translation elongation factor 1A. Here, we show that plitidepsin distributes preferentially to lung over plasma, with similar potency against across several SARS-CoV-2 variants in preclinical studies. Simultaneously, in this randomized, parallel, open-label, proof-of-concept study (NCT04382066) conducted in 10 Spanish hospitals between May and November 2020, 46 adult hospitalized patients with confirmed SARS-CoV-2 infection received either 1.5 mg (n = 15), 2.0 mg (n = 16), or 2.5 mg (n = 15) plitidepsin once daily for 3 d. The primary objective was safety; viral load kinetics, mortality, need for increased respiratory support, and dose selection were secondary end points. One patient withdrew consent before starting procedures; 45 initiated treatment; one withdrew because of hypersensitivity. Two Grade 3 treatment-related adverse events were observed (hypersensitivity and diarrhea). Treatment-related adverse events affecting more than 5% of patients were nausea (42.2%), vomiting (15.6%), and diarrhea (6.7%). Mean viral load reductions from baseline were 1.35, 2.35, 3.25, and 3.85 log10 at days 4, 7, 15, and 31. Nonmechanical invasive ventilation was required in 8 of 44 evaluable patients (16.0%); six patients required intensive care support (13.6%), and three patients (6.7%) died (COVID-19-related). Plitidepsin has a favorable safety profile in patients with COVID-19.