Coronavirus Antiviral Services


RetroVirox has a menu of cell-based assays to evaluate experimental therapies and vaccines against coronaviruses, including SARS-CoV-2. The Company provides testing with SARS-CoV-2 pseudoviruses to evaluate entry inhibitors against the novel coronavirus causative agent of COVID-19. The pseudovirus assay utilizes HIV pseudoviruses coated with the viral spike (S) protein of SARS-CoV-2 (Wuhan isolate). The assay recapitulates the mode of entry of the novel coronavirus and it can be used for the following purposes:

•To determine the neutralizing activity of therapeutic antibodies

•To test experimental COVID-19 vaccines using antisera from inoculated animals or humans

•To evaluate small-molecule entry inhibitors targeting the S viral protein, the ACE-2 viral receptor, or host proteases and other targets involved in SARS-CoV-2 viral entry

The pseudovirus assay are an invaluable resource complementing the ongoing company’s efforts to test entry inhibitors against highly-pathogenic viruses, including SARS-CoV-2, Ebola, Lassa, and H5N1 avian influenza. Pseudovirus coated with the spike protein of SARS-CoV and MERS-CoV are also available, and pseudoviruses  expressing different S proteins derived from geographically distinct SARS-CoV-2 strains will become available in the future.

RetroVirox also performs in vitro assay against several milder forms of seasonal human coronaviruses (hCoV), including the betacoronavirus strain OC43, and the alphacoronavirus strain 229E (other strains may be available upon request). These assays use prevention of the virus-induced cytopathic effect (CPE) as a readout. Many of the experimental and repurposed drugs with activity against SARS-CoV-2 (another betacoronavirus) also display activity against seasonal hCoVs. Our assay with OC43 hCoV reveals coronavirus inhibitors at most stages of the virus life cycle, including entry, and viral replication. In this assay, the replication of OC43 is blocked by remdesivir and chloroquine, two drugs with demonstrated antiviral activity against SARS-CoV-2. Our hCoVs assay can be used as a preliminary screen of experimental therapies against the novel coronavirus.

Both assays, the SARS-CoV-2 HIV pseudovirus, and the hCoV assays, are amenable for the screening of several thousand molecules per week. In addition, the company is optimizing assays against the live infectious SARS-CoV-2. We anticipate this assay will be offered to our Customers soon. Please email us to know more about this and other assays may be available in the near future.

For additional information about coronavirus antiviral services call us at (858) 232-7919 or contact us at

To see more information about antiviral assays offered against other viruses click on the following links:

AAV Neutralization Assays



Influenza Panel (20 strains)

Human Respiratory Syncytial Virus (HRSV)

Dengue (DENV) and ZIKA (ZIKV)


Human Cytomegalovirus (HCMV)

Human Rhinovirus (HRV)

HIV Pseudoviruses for Neutralization Assays

Highly Pathogenic Viruses

HTS Campaigns with Live Virus

Multi-virus panel

Consultancy Services