​​​COLUMBUS, Ohio — Hospitals are enrolling patients for a nationwide clinical trial examining whether existing medications could be repurposed to treat COVID-19 patients with mild to moderate illness, researchers said.

What You Need To Know

  • Researchers are conducting further studies of several drugs that have shown promise

  • Dozens of U.S. hospitals are part of the National Institutes of Health ACTIV-6 clinical trial

  • An infectious disease doctor says drug repurposing could have global impacts for patients

The ACTIV-6 trial backed by the National Institutes of Health is studying three drugs — fluvoxamine, an antidepressant; fluticasone, an inhaled steroid; and ivermectin, a drug for parasitic diseases. They are all previously FDA approved, but are not approved to treat COVID-19.

Infectious disease specialist Dr. Martin Gnoni of Cincinnati-based TriHealth, who is overseeing the health system’s participation in the study, said repurposed medications are generally cheap and widely available.

“Repurposed medications are well-known drugs by the medical community with a well-recognized safety profile and worldwide use,” Gnoni said. ”Some of these drugs have been in the market for decades and have been widely used in different countries and clinical settings.”

Health care providers can refer eligible patients who test positive to possibly be one of 15,000 people in the ACTIV-6 trial through participating hospitals like TriHealth. Eligible outpatients who are enrolled take one of the drugs or a placebo.  

Researchers are looking to see if the medications can help patients recover faster and avoid hospitalization. 

Gnoni noted that more therapeutic options are becoming available in the U.S., like oral antiviral pills, but he said a repurposed drug option could increase access to treatments and be an added defense alongside vaccines.

“There is no doubt that if we show that some cheap and widely available drugs can help fight mild-moderate COVID-19 through the improvement of symptoms and avoidance of hospitalization that would be a game-changer,” he said. “These drugs are being investigated just to be added to the anti-COVID-19 armamentarium that we already have.”

With COVID-19 treatment, scientists are studying to see if therapies can target either the viral replication phase of the disease or the later stage which is characterized by inflammation and tissue damage in severe cases, Gnoni said. These three drugs have shown some promise in limited trials or studies and have been prioritized by the NIH for further investigation. 

“Some of the repurposed drugs like ivermectin showed some interesting anti-viral properties ‘in-vitro’ (on the laboratory) and some others are thought to be mainly anti-inflammatory. Of note, sometimes there is no correlation between ‘in-vitro’ and ‘in-vivo’ results, that's why we conduct these complex clinical trials,” Gnoni said.

Even if a drug looks promising in the laboratory, it may turn out that the dosage required to achieve the desired effects may be too high and could risk significant adverse effects and toxicity, Gnoni said.

Physicians have expressed concern in particular about the drug ivermectin, which some COVID-19 patients have taken in doses larger than what is recommended for humans.

Gnoni said the ivermectin dosages for the ACTIV-6 trial are weight-based and safe for patients, stressing that participants are only given a small number of tablets. 

Researchers leading the clinical trial said ivermectin should not be taken outside the setting of a study like this because its benefits and risks are uncertain and pending further analysis.