Coronavirus disease 2019 (COVID-19) is caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2/2019-nCoV) and has developed into a pandemic with serious global public health and economic sequelae. As of June 30, 2020 over 10,000,000 cases have been confirmed worldwide leading to over 500,000 deaths (https://coronavirus.jhu.edu/map.html). Currently no vaccine exists, however chloroquine and hydroxychloroquine have been documented as potentially having antiviral properties with efficacy against COVID-19 disease. Chloroquine is used in the treatment of malaria and amebiasis and is still used in the prophylaxis of malaria. Hydroxychloroquine sulfate is a derivative of Chloroquine that has been demonstrated to be much less (~40%) toxic than Chloroquine in animals. Hydroxychloroquine is widely used to treat autoimmune diseases, due to its immunomodulatory properties, such as systemic lupus erythematosus and rheumatoid arthritis, with an excellent safety profile. In vitro studies have suggested that their mode of action in COVID-19 disease is blockade of SARS-CoV-2 transport from endosomes to endolysosomes, which appears to be a requirement to release the viral genome. Clinical investigation has found that high concentrations of cytokines are detectable in the plasma of critically ill patients infected with SARS-CoV-2, suggesting that cytokine storm is associated with disease severity; therefore, Chloroquine/ hydroxychloroquine may reduce this response by acting as anti-inflammatory agents in accord with their use in autoimmune disease, where their reduction in cytokine response has been extensively researched and demonstrated.~Favipiravir is an antiviral drug developed in Japan (as noted in the data sheets) that it is a pyrazinecarboxamide derivative with activity against influenza viruses, west nile virus, yellow fever virus, foot and mouth disease virus as well as against flaviviruses (i.e. arenaviruses, bunyaviruses and alphaviruses). Its mode of action is through inhibition of viral RNA-dependent RNA polymerase. In February the drug was used for COVID-19 disease in China and was declared effective in treatment, and a report published (in press) comparing Favipiravir with Lopinavir /ritonavir suggested that Favipiravir was superior for prevention of disease progression and viral clearance.~The Solidarity Trial is a global pragmatic clinical trial being undertaken by WHO that aims to explore the efficacy of different treatment modalities for SARS-CoV-2. An application for Bahrain to join the study for collaboration has been made. In The Solidarity Study there will be four treatment modalities investigated, including chloroquine phosphate alone, remdesivir, lopinarvir with ritonavir or lopinarvir with ritonavir plus interferon. Favipiravir is not included, and therefore this study will not be replicating features of The Solidarity Trial but instead will provide additional and novel findings on favipiravir efficacy.
Hydroxychloroquine is widely used to treat autoimmune diseases. Clinical investigation has found that a high concentration of cytokines were detected in the plasma of critically ill patients infected with SARS-CoV-2, therefore, hydroxychloroquine as anti-inflammatory agents may reduce this response in accord with their use in autoimmune disease where the cytokine response can be reduced.~Favipiravir is an antiviral drug developed in Japan that the data sheet notes that it is a pyrazinecarboxamide derivative with activity against influenza viruses, west nile virus, yellow fever virus, foot and mouth disease virus as well as against flaviviruses, arenaviruses, bunyaviruses and alphaviruses. In February the drug was used for COVID-19 disease in China and was declared effective in treatment, and a report published (in press) comparing Favipiravir with Lopinavir /ritonavir suggested that Favipiravir was superior for prevention of disease progression and viral clearance.~The objective of this pilot study is to compare three arms: hydroxychloroquine; favipiravir; standard care (no specific SARS-CoV-2 treatment) only, in symptomatic patients infected by SARS-CoV-2 in an open label randomized clinical trial. The difference between groups will allow an effect size to be determined for a definitive clinical trial.