The Briefing provides an at-a-glance view of some important developments in the information universe surrounding COVID-19. The views presented here are solely those of ECRI Horizon Scanning and have not been vetted by other stakeholders.

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The quest to develop antivirals to treat COVID-19 before hospitalization is at a turning point. Study results were reported for molnupiravir (Lagevrio), which cut the risk of hospitalization and death by 50%, and results are also available for Paxlovid,  which decreased risk by 89% (see Topics to Watch). Developers are now executing plans to submit for Emergency Use Authorization (EUA) as soon as possible to make these treatments available to patients. 

Concerns exist, however, regarding treatment timing, the risks of antiviral resistance due to viral mutations, and the risks to patients taking the medicine. In addition, antiviral drugs must be taken while the virus is replicating, but before widespread inflammation begins. Some experts, interviewed by Science, do not share these concerns though and note that the combination of 2 antivirals, such as molnupiravir and Paxlovid, could reduce the chance of the coronavirus becoming resistant to either drug.

Vaccination remains the best defense against severe COVID-19. A recent case-control study of more than 4000 hospitalized participants showed that mRNA vaccines are associated with an 85% reduction in COVID-related hospitalization.

EB05 to Treat Patients Hospitalized with COVID-19

At a Glance

  • Investigators are studying EB05, a monoclonal antibody, to treat patients hospitalized with a COVID-19–related respiratory disease.
  • EB05 purportedly inhibits Toll-like receptor 4 (TLR4) signaling to alter inflammatory signaling and dampen the proinflammatory cascade associated with severe COVID-19 outcomes, including organ failure and death.
  • Data released in October 2021 showed that EB05 given with standard of care resulted in a reduction in risk of death for multiple patient groups, including patients who were critically ill and hospitalized and patients with acute respiratory distress syndrome (ARDS) receiving supplemental oxygen.  
  • Basing its decision on favorable signals from a phase 2 trial, the manufacturer has announced plans to continue development in a phase 3 trial. 

PF-07321332 Plus Ritonavir (Paxlovid) to Treat Mild to Moderate COVID-19

At a Glance

  • PF-07321332 in combination with ritonavir (Paxlovid) is an oral antiviral that Pfizer is investigating to treat adults who have symptomatic COVID-19 in the outpatient setting.
  • A protease inhibitor, PF-07321332 is thought to hinder the activity of the main protease enzyme that the SARS-CoV-2 virus requires for replication.
  • Interim data from a phase 2/3 randomized controlled trial in nonhospitalized adult patients with COVID-19 at high risk of progressing to severe illness found that Paxlovid reduced hospitalization or death by 89% in patients treated within 3 days of symptom onset.
  • Basing its decision on these data, the manufacturer plans to submit an EUA to the US Food and Drug Administration (FDA) for Paxlovid.

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Commentary in this COVID-19 Scan reflects preliminary views of ECRI Horizon Scanning and internal ECRI stakeholders.
The information contained in this document has not been vetted by other stakeholders.

We welcome your comments on this Scan. Send them by email to [email protected].

Posted: November 22, 2021

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