A Randomized Open-label Prophylaxis Trial Among Migrant Workers at High-risk of COVID-19 (DORM Trial)

In December 2019, a novel coronavirus, now called COVID-19, emerged as a global health threat from Wuhan, China. Within weeks, the contagious virus spread within and between communities, causing a lower respiratory tract infection dominated by symptoms of fever, cough and sore throat. The incubation period was estimated at between 5 to 7 days, but could last as long as 14 days. Although COVID-19 causes a mostly mild and self-limiting disease, respiratory involvement has been reported in about 5% of the population, requiring supplemental oxygen and even ventilatory support to relieve hypoxia. Alveolar damage, fibrosis and consolidation have been reported in radiologic and post-mortem studies. Existing data suggest a mortality rate of COVID-19 is approximately 1-2%, higher among individuals with pre-existing comorbidities and in healthcare systems with suboptimal access to ventilatory support.

Given its high transmissibility, COVID-19 has quickly spread across the globe within a short interval. By 27 April 2020, over 3 million people around the world have been diagnosed with COVID-19, and more 200,000 have succumbed to the disease. As a proportion of patients manifest mild or no symptoms, these numbers are likely an underestimate of the actual number of patients with COVID-19. More disconcertingly, patients are known to shed viruses despite mild or no symptoms, making it essential that a collective approach against COVID-19 incorporate active pharmacological treatment to prevent or mitigate virus pathogenesis prior to its potential evolution to cause respiratory distress. To date, clinical trials have focused on the treatment of hospitalised patients diagnosed with COVID-19; only few have examined the clinical benefits of pharmacological agents despite few compelling in vitro data.

The relatively high transmission of COVID-19 in a closed dormitory environment of migrant workers in Singapore presents a real-life scenario where a prophylaxis treatment could reduce the impact of the disease. In Singapore, there are well grounded concerns an excess in cases could pose the possibility of strain in healthcare system and mentally drain her workers. The availability of an effective prophylaxis treatment is highly desirable to potentially reduce this burden. Data from the current study could also have implications on how future outbreaks in high-density areas should be managed, especially when residents are subjected to quarantine and isolation.