Suramin inhibits SARS-CoV-2 infection in cell culture by interfering with early steps of the replication cycle
drug discovery/repurposing therapeutics virology
Authors: Clarisse Salgado Benvindo da Silva et al.
Link to paper: https://doi.org/10.1101/2020.05.06.081968
Journal/ Pre-Print: bioRxiv
Tags: Drug discovery/Drug repurpose, Therapeutics, Virology
1. The antiparasitic drug suramin inhibits SARS-CoV-2 replication and decreases viral load in cell culture
2. It acts on early steps of SARS-CoV-2 replication, likely viral entry.
3. Suramin demonstrates potent anti-viral efficacy against SARS-CoV-2 in a primary human epithelial airway cell infection model.
The study identifies the already approved antiparasitic drug suramin as a potential treatment against SARS-CoV-2 infection. Suramin protects Vero E6 cells from SARS-CoV-2 induced cytopathic effects and inhibits the virus with a selectivity index higher than 250. No severe toxicity was observed. Viral RNA (intracellular and extracellular) and infectious virus load was also reduced in cultured human lung epithelial cells (Calu-3). Post-infection assays indicated that an early step of the replication is inhibited, most likely preventing SARS-CoV-2 entry into cells. These findings were reproduced in primary human airway epithelial cell cultures, the most relevant ex vivo model for human coronavirus research
Impact for SARS-CoV2/COVID19 research efforts
Inhibit of SARS-CoV2/COVID19 transmission
Treat of SARS-CoV2/COVID19 positive individuals
· In vitro study
Strengths and limitations of the paper
Novelty: The compound is already used as an anti-parasitic drug, but this paper first identifies suramin as an interesting candidate to further evaluate its potential for the treatment of SARS-CoV-2.
Standing in the field: Suramin is known to have broad-spectrum antiviral effects (amongst others on HIV and hepatitis C virus), whereby studies also reported the inhibition of virus entry or binding.
Appropriate statistics: Due to small samples size no statistical tests were performed.
Viral model used: Clinical isolate SARS-CoV-2/Leiden-002 (from a nasopharyngeal sample at LUMC).
Translatability: Suramin administration is required in the early stages of SARS-CoV-2 infection to inhibit infection and may protect lungs/other organs of already symptomatic patients. The standard treatment is done intravenously, but maybe even an aerosolized form could be considered (plenty of further studies needed).
Main limitations: Suramin functions in the early phase of infection, whereas the standard intravenous administration is more an option for seriously ill COVID-19 patients. Previous clinical trials of suramin were terminated owing to side-effects in patients. It is crucial to conduct many more tests before any conclusions on possible benefits for COVID-19 patients can be drawn.