FDA approved few drugs under Emergency Use Authorization (EUA) to treat COVID-19
Symptomatic treatment and supportive care remain the mainstay of treatment
Further studies are required to prove the efficacy and safety of the investigational drugs
COVID-19 is an infection caused by the novel coronavirus, SARS-CoV-2. There is no approved treatment available for COVID-19. Most of its patients develop mild symptoms, which usually resolves with supportive care and does not require intensive care. The U.S. Food and Drug Administration (FDA) has not approved any drug to treat or prevent the COVID-19 yet.
Scientists around the world are working day in and out to develop an effective treatment for COVID-19. The COVID-19 treatment strategies that are being investigated are Hydroxychloroquine, Corticosteroids, Antivirals, and Antibodies. However, recent studies show no signs of efficacy but maximum adverse effects, even death, are associated with these drugs.
Convalescent Plasma Therapy
Plasma therapy involves the transfusion of antibodies from the COVID-19 recovered donor to a patient with severe COVID-19. This technique of antibody transfer has been used in the past to treat various diseases like polio, measles, chickenpox, and SARS. Donor antibodies help in fighting against the SARS-CoV-2 virus in the recipient. It helped in decreasing the severity of symptoms and shortening the duration of illness in COVID-19 patients. More studies may be required to prove its efficacy. The FDA has approved its use in severe and life-threatening COVID-19 treatment.
Scientists are working on various antiviral drugs that were previously used to treat dangerous viral infections like SARS, MERS, and Ebola. These drugs are being investigated to demonstrate their safety and efficacy in treating COVID-19.
Remdesivir was effective in treating the coronavirus that caused SARS and MERS. It is an RNA polymerase inhibitor, which stops the virus from multiplying inside the cell. Some lab evidence showed that it killed the COVID-19 virus and decreased the viral load. The FDA has approved of the Emergency Use Authorization (EUA) of remdesivir in adults and children with moderate to severe illness. Initially, it was approved to be used in patients with COVID-19 pneumonia and drop in oxygen levels to 94% or lower. Recently, remdesivir received approval to be administered to any patient admitted to the hospital with COVID-19 pneumonia, irrespective of their oxygen level.
Favipiravir is an antiviral drug that inhibits viral replication. It was effective against the Ebola virus, influenza virus, and norovirus. Studies showed a higher recovery rate and shortened duration of illness in COVID-19 patients treated with Favipiravir. Clinical trials are ongoing to ascertain the safety and efficacy of Favipiravir in treating COVID-19. This drug is not available in the United States.
Hydroxychloroquine and Chloroquine
These two drugs are used in the treatment of malaria and inflammatory disorders like lupus and rheumatoid arthritis. Research studies showed that it killed the SARS-CoV-2 virus in the cultures outside the human body by inhibiting the cell attachment and its entry into the cell. However, hydroxychloroquine is associated with adverse side effects like cardiac arrhythmia. Several recent studies also proved it to be ineffective. Due to its potential side effects and lack of efficay, the FDA has disapproved the emergency use authorization of Hydroxychloroquine for COVID-19 treatment.
Azithromycin is an antibiotic with anti-inflammatory properties. Antibiotics are ineffective against viruses, but the anti-inflammatory property of Azithromycin helps in inhibiting the over-active immune response in COVID-19. There are insufficient data regarding its efficacy in fighting against the COVID-19 virus. It is used in some individuals with COVID-19 pneumonia to prevent secondary bacterial infection on top of the viral pneumonia.
Dexamethasone and methylprednisolone are potent anti-inflammatory drugs. They help in improving symptoms in patients with severe COVID-19. Steroids are indicated in patients that require supplemental oxygen therapy or are on mechanical ventilation. RECOVERY trial conducted in the UK demonstrated that Dexamethasone is life-saving in the affected individuals requiring oxygen therapy or on the ventilators. Dexamethasone does not really kill the virus; it reduces the impact of the inflammatory response instigated by the virus. Markedly elevated inflammatory substances cause damage to the organs. Dexamethasone and other steroid drugs used in COVID-19 patients reduce the inflammation and thus the impact of the disease process.
To date, health experts are currently investigating and developing various drugs as a potential treatment for COVID-19. However, the FDA has not approved any viable strategy for the prevention of COVID-19. Symptomatic treatment and supportive care remain the mainstay of treatment in more than 80% of the patients until new advances are made.
Tocilizumab or Actemra
This is an immunosuppressive drug used to treat rheumatoid arthritis. This drug is used in severe and critically ill COVID-19 patients. It is a monoclonal antibody that works against the interleukin-6 receptor (IL-6R). Interleukin-6 (IL-6) plays an important role in immune response. By inhibiting IL-6, Actemra reduces the organ damage caused by the severe inflammatory response instigated by the SARS-CoV-2 virus. There are no extensive research studies on this drug. While some studies showed benefit, few recent studies questioned its overall efficacy. Nonetheless, it still remains part of the institutional protocol at several hospitals. Several other similar monoclonal antibodies are being tested now.
Colchicine is a commonly used drug to treat gout. It has significant anti-inflammatory properties. A study conducted on 105 patients in Greece demonstrated that the patients who received colchicine seemed to do better when compared to patients who did not receive colchicine. The study showed that clinical deterioration is slower in individuals who received colchicine. This drug is still not commonly used to treat COVID-19 yet. More research needs to be done to provide guidance regarding its utility. It is not approved by FDA yet.
Ivermectin: This drug is primarily used to kill parasites.It is prescribed in few Asian countries to treat mild to moderate COVID-19 disease. There is no strong evidence to prove that it is effective. It is not approved by the FDA to be used in the United States.
Lopinavir and Ritonavir: This combination is used to treat HIV patients. During the early phase of the COVID-19 pandemic, Lopinavir-Ritonavir combination was used to treat COVID-19 patients. However, multiple research studies demonstrated that they are not effective. This combination is pulled out of the treatment protocols in all the hospitals.
Deftereos SG, Giannopoulos G, Vrachatis DA, et al. Effect of Colchicine vs Standard Care on Cardiac and Inflammatory Biomarkers and Clinical Outcomes in Patients Hospitalized With Coronavirus Disease 2019: The GRECCO-19 Randomized Clinical Trial. JAMA Netw Open. 2020;3(6):e2013136. doi:10.1001/jamanetworkopen.2020.13136