Research response to coronavirus disease 2019 needed better coordination and collaboration: a living mapping of registered trials

J Clin Epidemiol. 2021 Feb:130:107-116. doi: 10.1016/j.jclinepi.2020.10.010. Epub 2020 Oct 21.


Objectives: Researchers worldwide are actively engaging in research activities to search for preventive and therapeutic interventions against coronavirus disease 2019 (COVID-19). Our aim was to describe the planning of randomized controlled trials (RCTs) in terms of timing related to the course of the COVID-19 epidemic and research question evaluated.

Study design and setting: We performed a living mapping of RCTs registered in the WHO International Clinical Trials Registry Platform. We systematically search the platform every week for all RCTs evaluating preventive interventions and treatments for COVID-19 and created a publicly available interactive mapping tool at to visualize all trials registered.

Results: By August 12, 2020, 1,568 trials for COVID-19 were registered worldwide. Overall, the median ([Q1-Q3]; range) delay between the first case recorded in each country and the first RCT registered was 47 days ([33-67]; 15-163). For the 9 countries with the highest number of trials registered, most trials were registered after the peak of the epidemic (from 100% trials in Italy to 38% in the United States). Most trials evaluated treatments (1,333 trials; 85%); only 223 (14%) evaluated preventive strategies and 12 postacute period intervention. A total of 254 trials were planned to assess different regimens of hydroxychloroquine with an expected sample size of 110,883 patients.

Conclusion: This living mapping analysis showed that COVID-19 trials have relatively small sample size with certain redundancy in research questions. Most trials were registered when the first peak of the pandemic has passed.

Keywords: COVID-19; Clinical trial; Living mapping; Meta-analysis; Prevention; Systematic review; Treatment.

MeSH terms

  • COVID-19 / prevention & control
  • COVID-19 Drug Treatment*
  • Epidemiologic Research Design
  • Female
  • Geographic Mapping
  • Humans
  • Hydroxychloroquine / therapeutic use*
  • Internet
  • Italy
  • Male
  • Pandemics / prevention & control*
  • Randomized Controlled Trials as Topic
  • Sample Size
  • United States


  • Hydroxychloroquine