Multicenter, Randomized, Open-label, Non-commercial, Investigator-initiated Study to Evaluate the Efficacy and Safety of Chloroquine Phosphate in Combination With Telemedicine Care in the Risk Reduction of COVID-19 Related Hospitalization or Death, in Ambulatory Patients With COVID-19 Being at Risk of Serious Complications

Until now there are no evidence-based, good-quality data from sufficiently powered clinical trials supporting the use of any antiviral medicines or immunomodulatory therapies in the management or prophylaxis of COVID-19; however there are currently being initiated studies in Europe and U.S., and a few registered studies are ongoing in China. Currently two groups of medicines are hypothesized to be effective therapeutic options in COVID-19: (1) classical antiviral drugs interfering with pathogen dissemination / replication, and (2) compounds inhibiting host inflammatory reactions, especially (and potentially selectively) in respiratory tract / system (cytokine inhibitors and specific antibodies). Special hopes are placed in quinoline derivatives such as chloroquine (CQ), based on some unpublished data from China and a few experiments in vitro. CQ is an old antimalarial drug that has been used for more than 50 years in the therapy and prevention of this parasitosis. Anti-inflammatory features of quinolone derivatives such as CQ or hydroxychloroquine have also been used in rheumatology (for the therapy of lupus erythematosus or rheumatoid arthritis) due to the inhibition of the production of proinflammatory cytokines. The effectiveness (and safety) of CQ in COVID-19 has not been investigated in sufficiently powered RCTs until now.