#StayHome: Efficacy of Early Hydroxychloroquine in Outpatients to Reduce Secondary Hospitalisation and Household Transmission of COVID-19 in Switzerland: A Double-blind, Randomised, Placebo-controlled Trial

BACKGROUND Despite drastic quarantine measures, COVID-19 continues to propagate and threatens global healthcare systems by saturating their capacity with high transmissibility and the particularly protracted length of stay needed by those requiring intensive care. Indeed, once patients advance to the ICU, prognosis is poor and it is thus critical to test medications that may prevent complications and reduce viral shedding. i.e. to protect ambulatory patients and their families from complications and transmission and allow them to #StayHome.

To date, no treatment has been reliably demonstrated as effective in COVID-19 patients.

Hydroxychloroquine (HCQ), a common and well tolerated medication, has shown promise in vitro for reducing viral replication (for SARS-CoV-2 as well as other coronaviruses with pandemic potential such as SARS-CoV-1 and MERS). Since then, several small-scale hospital-based clinical studies have indicated the potential for reduced viral shedding and hospitalisation as well as favourable evolution of lung pathology. If started earlier, this treatment could prevent complications requiring hospitalisation and intensive care, which may not be available in low-income countries.

Robust clinical trials are required to assess the potential of HCQ in COVID-19.

OBJECTIVES This trial assesses the efficacy of early treatment with HCQ in COVID-19 outpatients to reduce the incidence and severity of complications including secondary hospitalisation, ICU admissions, lung pathology and death. Secondarily, this trial will also assess its efficacy to reduce viral transmission among household contacts during self-quarantine. The clinical data collected in this trial will also be critical in creating early prognostication models to better predict healthcare needs and have evidence-based prioritization of resource allocation, which is especially critical in low-resource settings.

METHODS The trial will recruit 800 SARS-CoV-2+ patients and their household contacts at triage sites across Switzerland. Patients included are 1) at risk of poor outcome (comorbidities or >65y) and 2) well enough to self-isolate at home. These patients will be randomised 1:1 in HCQ:Placebo and given 6 days of early treatment (within 24 hours of the SARS-CoV-2 test). Intensive pragmatic multiparameter at-home follow-up (including point-of-care lung ultrasound in some sites) will continue until their outcome (resolution, or complications, such as hospitalisation, ICU admission, death). Household contacts will have before and after serological testing and social distancing knowledge and practices questionnaires to assess risk factors for infections. The household attack rate of new-onset infections can then assess the efficacy of HCQ to prevent transmission.