Therapeutic Application of Chloroquine in Clinical Trials for COVID-19

Divya RSJB Rana; Santosh Dulal

Modern and robust scientific interventions at national and international level for prevention, containment and treatment has protected mankind from various deadly diseases like Ebola, Severe Acute Respiratory Syndrome, Middle East Respiratory Syndrome, etc. in the contemporary parameters. The Spanish flu about one hundred years ago claimed about up to 50 million lives (21) as modern scientific knowledge were contemporarily lacking and limited. As predicted, in the absence of these measures, if 60% of global population were infected as forecasted by experts, and approximately 20% required treatment of chloroquine phosphate or hydroxychloroquine sulphate (22) , the cost could range tens of thousands USD per million population (Table 3) . (Table 4) . Thus more studies are warranted to confirm the efficacy and safety for use of these medications. In spite of that, continued efforts to try different dosages in ethically valid clinical trials is required for the assessment of effective and safe dosage administration. This can importantly contribute to guide the medical professionals for prescribing the accurate interventions and also contribute to pharmaceutical companies for deciding appropriate manufacturing pathways. While hydroxchloroquine has low dosage requirements and lesser side effects, the comparative price for complete prescribed treatment is more than five times of chloroquine phosphate (24) . While malaria is endemic in poor parts of the world, the prevalence is still too less than the panic and feared caused by prevalence of COVID-19 prompting pharmaceuticals for scaling up for the production of chloroquine. As chloroquine has significant adverse events, effective short-course dosing is very important. Moreover, both of these drugs are prescribed for weeks to months for various indications (8,11) and the interventions for short disease course (2 weeks for mild and 3-4 weeks for severe and critical cases) (22) of COVID-19 may not significantly hamper treatment. Other antiviral drugs in pipeline may not be very useful as their productions and supplies to the developing countries may require lengthy timeframe whereas mass production of chloroquine and hydroxychloroquine is already in place in malaria endemic developing countries.