|Remdesivir||In-vitro effective against COVID-19; Effective (esp. prophylactically) against MERS in macaque monkeys; More effective than lopinavir/ritonavir against MERS in mice|
|Chloroquine||In-vitro effective against COVID-19; In-vitro effective against SARS; Not in-vitro effective against MERS in monocyte-derived cells|
|Cinanserin||In-vitro effective against COVID-19;In-vitro effective against SARS|
|Lopinavir/Ritonavir||Human retrospective evidence of effectiveness in MERS and SARS but not COVID-19; In-silico predicted effectiveness against COVID-19|
|Indinavir||In-silico predicted effectiveness against COVID-19; Not effective in-vitro against SARS|
|Thalidomide||Improved symptoms in one case study of severe COVID-19|
An in-silico study of HIV drugs for their docking affinity to a key enzymes in the COVID-19 virus – RdRp, the main protein for RNA replication – found an almost perfect match in the antiviral drug remdesivir, suggesting it might be a good candidate drug for treating COVID-19.
Remdesivir also inhibits the COVID-19 virus in vitro.
Remdesivir is effective at reducing the clinical signs of infection and viral load from MERS coronavirus in rhesus macaque monkeys; if given prophylactically, it prevents the monkeys from getting any disease symptoms at all and keeps their viral loads negligible. In mice, remdesivir is more effective than lopinavir/ritonavir in improving pulmonary function and reducing viral load from MERS infection.
In 3 US patients treated with remdesivir, 2 patients saw fever drop immediately upon receiving the drug (the third didn’t have a fever); one was able to go off supplemental oxygen; all recovered.
Remdesivir is currently in trials in China and the US for COVID-19.
A brief summary document  claims that clinical trials in China including over 100 patients have found the antimalarial drug chloroquine phosphate “superior to control treatment” in treating COVID-19 pneumonia and shortening disease course. The paper provided no documentation about experimental methods.
Chloroquine also inhibits the replication of the COVID-19 virus in vitro, as well as the SARS coronavirus in vitro. It does not inhibit the MERS coronavirus in vitro in a culture of monocyte-derived cells.
Chloroquine frequently causes gastrointestinal side effects (diarrhea, nausea), problems with visual acuity, insomnia, and paresthesias (prickling skin sensations.) More rarely, chloroquine can cause psychiatric symptoms like depression.
Cinanserin is a serotonin receptor antagonist which was also found to inhibit the replication of the SARS virus in vitro. Cinanserin inhibits the activity of COVID-19’s main protease in vitro, and inhibits the virus’s replication in vitro.
Cinanserin also inhibits the replication of the SARS coronavirus in vitro.
Lopinavir/Ritonavir is a combination of two antiviral drugs approved for the treatment of HIV.
In one Korean patient, aged 54, with mild pneumonia and a diagnosis of COVID-19, treatment with the antiviral drug combination of lopinavir and ritonavir diminished coronavirus load to undetectable levels.
Lopinavir/Ritonavir was also used by the Thai infectious disease team to successfully treat patients with severe COVID-19.
Lopinavir also had a high binding affinity to the COVID-19 protein 3CL-PRO in an in-silico screen of 3118 FDA-approved drugs.
Lopinavir is a protease inhibitor, effective in vitro against the main protease of the SARS coronavirus; it also has in vitro antiviral activity against SARS-CoV. Lopinavir reduced viral load and clinical symptoms of the MERS coronavirus in mice and marmoset monkeys.
In human SARS cases, treatment with lopinavir was associated with lower death rate (2.3%) and intubation rate (0%) compared with standard treatment (11% and 15.6% respectively.). Another case-control study of SARS found a lower rate of ARDS in patients treated with lopinavir (2.4% vs 28.8%). 
A retrospective study of 40 patients found that post-exposure prophylaxis including lopinavir/ritonavir reduced the spread of MERS-CoV by 40% in healthcare workers. However, a retrospective study of 134 COVID-19 patients found no significant difference between lopinavir/ritonavir treatment, Abidol treatment, and control treatment.
Indinavir is an antiviral drug used to treat HIV.
In an in-silico screen of the binding affinity of 3118 FDA-approved drugs to several key enzymes of the COVID-19 virus, the highest-affinity drug for the protease PDB-6LU7 was indinavir, an antiviral drug approved for use against HIV. (Even higher affinity were human proteins that closely resemble the enzyme’s ligand – ACE2 and GHRP-2.) Indinavir also had a high binding affinity to another COVID-19 protein, 3CL-PRO.
However, in an in-vitro test against the SARS coronavirus, indinavir did not block replication.
Thalidomide is an immunomodulatory drug used to treat cancers.
A 45-year-old woman with a severe case COVID-19, with fever, pneumonia, dyspnea, nausea, and vomiting, improved and went into remission after being treated with thalidomide, which has anti-inflammatory effects, reducing the “cytokine storm” responsible for the severe symptoms of COVID-19.
Gao, Jianjun, Zhenxue Tian, and Xu Yang. “Breakthrough: Chloroquine phosphate has shown apparent efficacy in treatment of COVID-19 associated pneumonia in clinical studies.” BioScience Trends (2020).
Lim, Jaegyun, et al. “Case of the Index Patient Who Caused Tertiary Transmission of COVID-19 Infection in Korea: the Application of Lopinavir/Ritonavir for the Treatment of COVID-19 Infected Pneumonia Monitored by Quantitative RT-PCR.” Journal of Korean medical science 35.6 (2020).
Chang, Yu-Chuan, et al. “Potential therapeutic agents for COVID-19 based on the analysis of protease and RNA polymerase docking.” (2020).
Contini, Alessandro. “Virtual screening of an FDA approved drugs database on two COVID-19 coronavirus proteins.” (2020).
Jin, Zhenming, et al. “Structure-based drug design, virtual screening and high-throughput screening rapidly identify antiviral leads targeting COVID-19.” bioRxiv (2020).
Yao, Tian‐Tian, et al. “A Systematic Review of Lopinavir Therapy for SARS Coronavirus and MERS Coronavirus–A Possible Reference for Coronavirus Disease‐19 Treatment Option.” Journal of Medical Virology (2020).
Wang, Manli, et al. “Remdesivir and chloroquine effectively inhibit the recently emerged novel coronavirus (2019-nCoV) in vitro.” Cell research 30.3 (2020): 269-271.
Chen, Chengshui, et al. “Thalidomide combined with low-dose glucocorticoid in the treatment of COVID-19 Pneumonia.” (2020).
Vincent, Martin J., et al. “Chloroquine is a potent inhibitor of SARS coronavirus infection and spread.” Virology journal 2.1 (2005): 69.
de Wit, Emmie, et al. “Prophylactic and therapeutic remdesivir (GS-5734) treatment in the rhesus macaque model of MERS-CoV infection.” Proceedings of the National Academy of Sciences (2020).
Sheahan, Timothy P., et al. “Comparative therapeutic efficacy of remdesivir and combination lopinavir, ritonavir, and interferon beta against MERS-CoV.” Nature Communications 11.1 (2020): 1-14.
Tan, Emily LC, et al. “Inhibition of SARS coronavirus infection in vitro with clinically approved antiviral drugs.” Emerging infectious diseases 10.4 (2004): 581.
Cong, Yu, et al. “MERS-CoV pathogenesis and antiviral efficacy of licensed drugs in human monocyte-derived antigen-presenting cells.” PloS one 13.3 (2018).
Chen, Lili, et al. “Cinanserin is an inhibitor of the 3C-like proteinase of severe acute respiratory syndrome coronavirus and strongly reduces virus replication in vitro.” Journal of virology 79.11 (2005): 7095-7103.
Martins, Antonio Camargo, et al. “Side effects of chloroquine and primaquine and symptom reduction in malaria endemic area (Mâncio Lima, Acre, Brazil).” Interdisciplinary perspectives on infectious diseases 2015 (2015).