Do we already have a treatment for Coronavirus?


by Dr. C.H. Weaver M.D. 3/2020

To date, no specific antiviral drugs to prevent or treat human coronaviruses (HCoVs) infections are available. Effective treatment of the virus and its consequences will be the most effective approach to limit the pandemic given that a vaccine is over a year away and there is no guarantee it will be effective. A consensus is emerging that treating patients diagnosed with novel coronavirus pneumonia with chloroquine might improve the success rate of treatment, shorten hospital stay and improve patient outcomes. (1,2) Other existing medications that target inflammation are already being evaluated.

Coronaviruses are large, enveloped, single-stranded, positive-sense RNA viruses that have been recognized as human pathogens for about 50 years, but no effective treatment strategy has been approved. This shortcoming became evident during the SARS-CoV outbreak which was the start of numerous studies (1,2) and has been amplified by the recent global Coronaviruse COVID-19 pandemic.

About Chloroquine

Chloroquine is a clinically approved drug effective against malaria, and it is known to elicit antiviral effects against several viruses including human immunodeficiency virus type 1, hepatitis B virus, and herpes simplex virus type 1. (3-10) Chloroquine is also reported to inhibit the replication of some HoCov (10) and SARS-CoV (11) in vitro. Chloroquine can affect virus infection in many ways. Besides having a direct antiviral effect, chloroquine is endowed with immunomodulatory activity, suppressing the production and release of tumor necrosis factor alpha and interleukin 6, which mediate the inflammatory complications of several viral diseases. (13)

Coronavirus Update

Researchers have investigated the anti-coronaviral properties of chloroquine and by testing the in-vitro antiviral activity of chloroquine and it has been shown to inhibit some HCoV replication. Chloroquine has also been shown to prevent HCoV induced death in newborn mice. These results have led to the recent testing of chloroquine and hydroxychloroquine in humans impacted with the current COVID-19 strain implicated in the global pandemic with encouraging results. (13) Clinical trials are ongoing and results should be available shortly.

A report released by Chinese researchers on April 2 suggests hydroxychloroquine helped to speed the recovery of a small number of patients who were mildly ill from the coronavirus. ,

Cough, fever and pneumonia all recovered quicker, and the disease seemed less likely to become severe in people who received hydroxychloroquine than in a comparison group not given the drug.

The study was small and limited to patients who were mildly or moderately ill, not severe cases. Like many reports about the coronavirus, it was posted at medRxiv, an online server for medical articles, before undergoing peer review by other researchers.

Regeneron is testing an approved drug, called Kevzara, against Covid-19. The drug, targets inflammation, not the virus itself. A similar drug from Roche, Actemra, showed early promise in a study in China. Answers from that study might be available in weeks to months, if patients respond quickly.

Regeneron said in a press release that its scientists have isolated hundreds of virus-neutralizing antibodies from mice, and patients who have recovered from COVID-19. It will choose two of these based on their potency and other qualities like to be manufactured easily, and durability in the body. The antibodies target a protein on the virus’ outer shell, called the spike protein. Having two antibodies targeting the spike protein in the treatment, not one, should mean that it is more difficult for the virus to mutate in a way that will allow it to evade both antibodies.

Creating antibody drugs against the COVID -19 virus is seen as one of the more promising approaches. Teams of researchers at Biogen, Regeneron, Gilead, Eli Lilly and others have all announced plans to develop antibody drugs against the virus.

Study Results from Ongoing Trials


Common Flu Medication - Favipiravir


  1. Kouroumalis, E. A., and J. Koskinas. 1986. Treatment of chronic active hepatitis B (CAH B) with chloroquine: a preliminary report. Ann. Acad. Med. Singapore 15:149-152.
  2. Pardridge, W. M., J. Yang, and A. Diagne. 1998. Chloroquine inhibits HIV-1 replication in human peripheral blood lymphocytes. Immunol. Lett. 64:45-47.
  3. Rubin, M., H. N. Bernstein, and N. J. Zvaifler. 1963. Studies on the pharmacology of chloroquine. Recommendations for the treatment of chloroquine retinopathy. Arch. Ophthalmol. 70:474-481.
  4. Savarino, A., J. R. Boelaert, A. Cassone, G. Majori, and R. Cauda. 2003. Effects of chloroquine on viral infections: an old drug against today's diseases? Lancet Infect. Dis. 3:722-727.
  5. Savarino, A., L. Gennero, K. Sperber, and J. R. Boelaert. 2001. The anti-HIV-1 activity of chloroquine. J. Clin. Virol. 20:131-135.
  6. Singh, A. K., G. S. Sidhu, R. M. Friedman, and R. K. Maheshwari. 1996. Mechanism of enhancement of the antiviral action of interferon against herpes simplex virus-1 by chloroquine. J. Interferon Cytokine Res. 16:725-731.
  7. Tsai, W. P., P. L. Nara, H. F. Kung, and S. Oroszlan. 1990. Inhibition of human immunodeficiency virus infectivity by chloroquine. AIDS Res. Hum. Retrovir. 6:481-489.
  8. Blau, D., and K. V. Holmes. 2001. Human coronavirus HCoV-229E enters susceptible cells via the endocytic pathway, p. 193-197. In E. Lavi (ed.), The nidoviruses, coronaviruses and arteriviruses. Kluwer, New York, NY.
  9. Fouchier, R. A., N. G. Hartwig, T. M. Bestebroer, B. Niemeyer, J. C. de Jong, J. H. Simon, and A. D. Osterhaus. 2004. A previously undescribed coronavirus associated with respiratory disease in humans. Proc. Natl. Acad. Sci. USA 101:6212-6216.
  10. Savarino, A., J. R. Boelaert, A. Cassone, G. Majori, and R. Cauda. 2003. Effects of chloroquine on viral infections: an old drug against today's diseases? Lancet Infect. Dis. 3:722-727.

Health & Conditions