Post-exposure Prophylaxis clinical trials

Hydroxychloroquine Post-Exposure Prophylaxis for Coronavirus Disease (COVID-19) Among Health-Care Workers

Background: The rapid spread and high infectivity of severe acute respiratory syndrome coronavirus 2 (SARS-CoV2) makes identifying an effective prophylaxis agent highly important. One of the important target populations for such intervention who are at high risk of exposure are health care workers (HCWs) who may develop disease and/or expose patients and other HCWs. Hydroxychloroquine (HCQ), currently in usage for treatment of severe Coronavirus Disease 2019 (COVID-19), has in addition to in-vitro activities of inhibition of virus replication and immunomodulation, an important role in the inhibition of pre-entry step of the virus to host cells. Such activity in the early stage of infection may play a role in prevention of disease progression. Objectives: To evaluate the effect of HCQ in prevention of clinical disease and reduction of viral shedding among HCWs following exposure to confirmed COVID-19 patients. Study design: Multi-center, randomized controlled, superiority, open label trial Setting: The study will be conducted at Rambam Health Care Campus. Eligibility: Participants eligible for inclusion will include non-pregnant adult (>18 years old) HCWs who were exposed to a confirmed case of COVID-19 without full adherence to droplet precautions. Participants will be eligible in a period no longer than 72 hours after exposure. Intervention: HCQ will be given in the intervention group in a dosage regimen of 400mg BID in the first day followed by 200mg BID for overall 10 days. Participants in the control group will receive no treatment. Treatment will be started no longer than 72 hours following exposure. Outcomes: The primary outcome will be the number of participants who develop clinical signs compatible with COVID 19 (defined in full protocol) within 14 days of exposure. Secondary outcomes will include virologically-confirmed COVID 19, disease severity (need for hospitalization, mechanical ventilation and 30-day mortality) and viral shedding duration (time between first positive PCR to last of two consecutive negative tests) for confirmed COVID 19 cases. Sample size: The trial will test for HCQ's superiority assuming a primary outcome incidence of 20% in the control group and a reduction of 50% with HCQ. The sample size required for a power of 80% (alpha 0.05) is 291 participants per each group.