June 23, 2020
Remdesivir, an antiviral drug that has shown promise as a treatment for hospitalized COVID-19 patients, will soon be tested as an inhalable medication in hopes of reaching people at earlier stages of the disease, Gilead Sciences says.
The drug currently is only administered intravenously, necessitating it be given in hospital settings. An inhalable version delivered through a nebulizer potentially could be given at urgent care clinics and other outpatient settings.
Nebulizers turn liquid medicine into a fine mist, allowing people to inhale the medication through a face mask or mouthpiece. The hope is that an inhalable version of remdesivir could be used to treat people who test positive for the SARS-CoV-2 virus, but who only have mild symptoms or none at all, Gilead scientists say.
The U.S. Food and Drug Administration has granted remdesivir an Emergency Use Authorization for the treatment of hospitalized patients with severe COVID-19. The drug's safety and efficacy is still being investigated in clinical trials and formal drug approval has not been given.
Remdesivir slows down the replication of the coronavirus. Studies have found the drug can shorten recovery time for COVID-19 patients by an average of four days. However, it appears to offer the most clinical benefit to patients who have not needed mechanical ventilation.
This data supports further study in patients with earlier stages of the disease, Gilead Sciences CEO Daniel O'Day wrote in an open letter. The biopharmaceutical company will start to screen healthy volunteers for Phase 1 trials this week, with the expectation to be studying the drug in patients with COVID-19 by August.
While hopes are high in the Gilead camp, some medical experts caution that there are still many questions that need to be answered before this type of treatment can be considered.
Trials are needed to see if the antiviral is effective in inhalable form and to determine the dose that would provide the most benefit without causing adverse reactions. Plus, there is concern that viral particles could be spread through the use of a nebulizer, they said.
Gilead Sciences also is exploring other ways to get effective treatment options to COVID-19 patients. The possibilities include administering intravenous remdesivir at infusion centers and nursing homes, and pairing remdesivir with anti-inflammatory agents in clinical trials.
In the later stages of COVID-19, data suggests the body's inflammatory response causes the most potentially life-threatening complications. A combination therapy of an antiviral and an anti-inflammatory drug may be more effective for the most severely ill COVID-19 patients.
One upcoming study will look at remdesivir's effectiveness when combined with the JAK inhibitor baricitinib. Another will pair it with the Interleukin-6 receptor antagonist tocilizumab. Both of these drugs are already used to tamp down the overactive immune response that occurs in autoimmune diseases.
O'Day added that there are also ongoing trials to determine whether remdesivir may benefit vulnerable patient populations like children and pregnant women.
"Our commitment to remdesivir will continue now as we explore its full potential in the hope of helping many more patients with COVID-19," he wrote. "At the same time, our broader ongoing research in emerging viruses continues. We are committed to doing everything we can to help with this pandemic, while ensuring we are prepared for the next."
