As Cases Decline, Scientists Work to Develop Anti-COVID-19 Pill for Seasonal Variants
Antiviral pills against the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the novel coronavirus responsible for coronavirus disease 2019 (COVID-19), are showing promise in new clinical trials.
Scientists across the globe are suggesting SARS-CoV-2 will turn into a seasonal virus once the pandemic has officially come to an end. Cases of COVID-19 have drastically decreased nationwide, thanks largely to authorized vaccines from Pfizer–BioNTech, Moderna, and Johnson & Johnson.
But even while states ease pandemic-related restrictions such as mask mandates and social distancing, scientists are quickly working to develop an antiviral pill that can be used each season SARS-CoV-2 comes back around. Up to three of these pills have shown promise in clinical trials.
The best early therapies for COVID-19 currently consist of laboratory-produced antibodies. However, these monoclonal antibodies can be costly, and the administration of these therapies is sometimes difficult. For instance, these treatments require infusion into the patient’s blood, which can take time, more staff and greater clinic space.
Three new antiviral agents, however, may offer a solution to monoclonal antibody therapies. These three experimental antivirals have been designed to be given in the early stages of developing COVID-19 symptoms and prior to hospitalization. Each pill contains molecules to interfere with coronavirus replication.
Pfizer, the maker of one of the first authorized COVID-19 vaccines, has a potential anti-SARS-CoV-2 pill currently in early-stage trials. Pfizer launched its Phase I trial of the novel oral antiviral agent back in late March. Researchers are looking to determine the safety and optimal dose of the pill, dubbed PF-07321332, in a 60-person Phase I trial.
“We have designed PF-07321332 as a potential oral therapy that could be prescribed at the first sign of infection, without requiring that patients are hospitalized or in critical care,” said Pfizer’s Chief Scientific Officer and President of Worldwide Research, Development and Medical, Mikael Dolsten, MD, PhD., in a statement.
“At the same time, Pfizer’s intravenous antiviral candidate is a potential novel treatment option for hospitalized patients. Together, the two have the potential to create an end to end treatment paradigm that complements vaccination in cases where disease still occurs.”
Sagent Pharmaceuticals is also looking into camostat, a drug authorized in Japan in the 1980s for pancreatitis. Currently, camostat isn’t approved in the U.S., but scientists are holding out hope that it can provide robust and durable antiviral activity against the novel coronavirus. The drug has just completed Phase II testing. In this research phase, investigators are now examining data on the drug’s effectiveness and safety in hundreds of volunteers.
Both PF-07321332 and camostat are currently being evaluated in the National Institutes of Health’s ACTIV-2 trials. Camostat entered into the trials back in February. Two monoclonal antibodies from Brii Biosciences, BRII-196, and BRII-198, also recently advanced to Phase III in the ACTIV-2 trial. These antibodies are being testing for efficacy and safety in ambulatory patients with COVID-19.
Merck and Ridgeback Biotherapeutics’ molnupiravir, an investigational antiviral drug not involved in the ACTIV-2 trial, is another antiviral hopeful currently in Phase III testing. The drug was originally produced for SARS Co-V1 and MERS, making it one potential anti-SARS-CoV-2 drug that’s further along in research. The drug is undergoing efficacy and safety testing in a 1,500-person, late-stage trial.