Why is pre-exposure prophylaxis with hydroxychloroquine a safe and rationale approach against SARS-CoV-2 infection?

The potentiality of Hydroxychloroquine (HCQ) for pre-exposure prophylaxis against SARS-CoV-2 has not been explored in randomized controlled trials. However, there is rationale behind this potentiality in terms of demonstrated in-vitro effect of HCQ against SARS-CoV-2, safety profile of HCQ in healthy individuals and a recent observational study demonstrating benefits of HCQ prophylaxis in terms of a significant reduction (>80%) in the odds of SARS-CoV-2 infection in the health-care workers (HCWs) with the intake of six or more doses of HCQ prophylaxis as per the guidelines of the National Task Force for COVID-19 in India. Hence, pre-exposure prophylaxis with HCQ in appears to be a reasonable strategy in the current scenario for prevention of SARS-CoV-2 infection in healthy HCWs.