We are currently living in times of great uncertainty and the ideal approach to treating COVID-19 has been hotly debated. Although several therapies have been touted in the media, none have been proven effective.  The decision to use a drug is based principally on observational and anecdotal reports or extrapolated from indirect evidence. Most patients who test positive can be treated at home with rest and management of symptoms. Several experimental therapies have been tried on patients with moderate or severe disease.

Below, I will outline several of the drugs that appear to be the most promising.

Remdesivir.  Remdesivir is a recently developed antiviral medication. Administered by injection, remdesivir prevents the virus from replicating.¹ It has shown to be effective in treating viruses similar to COVID-19 including SARS and Middle East Respiratory Syndrome (MERS-COV). Remdesivir appears to prevent  COVID-19 from replicating in a laboratory setting. However, the activity of remdesivir against COVID-19 in sick patients has yet to be determined.² Several small case studies show promise of remdesivir as an agent against COVID-19.^3,4  The cases studies are limited in that they cannot compare remdesivir to no treatment or other possible treatments. Multiple larger randomized trials are currently underway to determine if remdesivir can be used as an agent against COVID-19.

What is the risk of using remdesivir before its effects are proven? Remdesivir can cause nausea, vomiting, liver and kidney damage, and potentially organ failure. In patients with kidney disease, remdesivir can build up in the body causing the side effects to last longer than normal.¹

Hydroxychloroquine/chloroquine. Much speculation exists about whether hydroxychloroquine and chloroquine, either alone or in combination with azithromycin, may help treat patients with COVID-19. Please refer to my previous post (see “What is up with hydroxychloroquine?“)  where I discussed hydroxychloroquine in detail. Currently, there is not enough data to say if hydroxychloroquine or chloroquine has a role in treatment of COVID-19.² The most recent research⁵ (published mid April 2020) indicates that hydroxychloroquine, either alone or with azithromycin, does not reduce the severity of the disease. In fact, patients who were given hydroxychloroquine were more than twice as likely to die and more likely to require a mechanical ventilator to breathe compared to those who did not receive  hydroxychloroquine.

Convalescent plasma. Researchers are investigating convalescent plasma as a potential therapy in patients with severe or life-threatening COVID-19. After a person recovers from COVID-19 they have antibodies to the disease in their blood. Within their blood, the plasma, a golden fluid that contains nutrients, can be separated from the red blood cells. There is hope that convalescent plasma can be given to people with severe COVID-19 to provide them with the antibodies needed to fight the virus and increase their chances of recovery.⁶

The Food and Drug Administration (FDA) has recently expanded access and approved convalescent plasma for emergency individual use.⁷ Several patients in case studies showed substantial improvement after they were administered convalescent plasma. This, however, does not establish a causal effect, and whether plasma is useful in therapy remains largely unknown. Additionally, hospitals face logistical challenges finding appropriate donors and establishing testing to confirm the antibodies in the plasma have activity against COVID-19. ^2,6

Tocilizumab. Tocilizumab inhibits the activity of Interleukin 6, a protein that affects the body’s response to infection and inflammation. Tocilizumab is approved by the FDA to treat rheumatoid arthritis and cytokine release syndrome.⁸  The basis for the use of tocilizumab to combat COVID-19 stems from reports of elevated Interleukin levels in patients with severe COVID-19. As with the other potential therapies, several cases indicate the positive impact of tocilizumab, but its place in therapy is still uncertain. Other Interleukin 6 inhibitors such as sarilumab and siltuximab, are also being evaluated in clinical trials.²

References

• LexiDrugs. Hydroxychloroquine. Updated March 2020. Accessed on 21 April 2020
• Coronavirus disease 2019 (COVID-19). Updated April 2020. Available at Uptodate.com. Accessedon 21 April 2020
• Lescure, F.X. et al. Clinical and virological data of the first cases of COVID-19 in Europe: a case series. Lancet Infect Dis. doi: https://doi.org/10.1016/S1473-3099(20)30200-0•
• Grein, J. et al. Compassionate Use of Remdesivir for Patients with Severe Covid-19.N Engl J Med.doi: 10.1056/NEJMoa2007016
• Magagnoli, J. et al. Outcomes of hydroxychloroquine usage in United States veterans hospitalized with Covid-19. (In Press) medRxiv preprint. April 2020.doi: https://doi.org/10.1101/2020.04.16.20065920
• Mayo Clinic. Convalescent plasma: Possible treatment for COVID-19? 2020. Available at: https://www.mayoclinic.org/diseases-conditions/coronavirus/expert-answers/convalescent-plasma/faq-20484383. Accessed on 21 April 2020.
• US Food and Drug Administration. Recommendations for Investigational COVID-19 Convalescent Plasma. Available at: https://www.fda.gov/vaccines-blood-biologics/investigational-new-drug-ind-or-device-exemption-ide-process-cber/recommendations-investigational-covid-19-convalescent-plasma. Accessed on 21 April 2020.
• LexiDrugs. Tocilizumab. Updated March 2020. Accessed on 21 April 2020.
• Michot, J.M. et al. Tocilizumab, an anti-IL6 receptor antibody, to treat Covid-19-related respiratory failure: a case report. Ann Onco 2020. doi: 10.1016/j.annonc.2020.03.300.