Hydroxychloroquine and Tocilizumab Therapy in COVID-19 Patients – An Observational Study

Abstract

AbstractBackgroundHydroxychloroquine has been touted as a COVID-19 treatment. Tocilizumab, an inhibitor of IL-6, has been proposed as a treatment of critically ill patients.ObjectiveTo describe the association between mortality and hydroxychloroquine or tocilizumab therapy among hospitalized COVID-19 patients.DesignRetrospective observational cohort study of electronic health records Setting: 13-hospital network spanning the state of New Jersey.ParticipantsPatients hospitalized between March 1, 2020 and April 22, 2020 with positive polymerase chain reaction results for SARS-CoV-2. Follow up was through May 5, 2020.Main OutcomesThe primary outcome was death.ResultsAmong 2512 hospitalized patients with COVID-19 there have been 547 deaths (22%), 1539 (61%) discharges and 426 (17%) remain hospitalized. 1914 (76%) received at least one dose of hydroxychloroquine and 1473 (59%) received hydroxychloroquine with azithromycin. After adjusting for imbalances via propensity modeling, compared to receiving neither drug, there were no significant differences in associated mortality for patients receiving any hydroxychloroquine during the hospitalization (HR, 0.99 [95% CI, 0.80-1.22]), hydroxychloroquine alone (HR, 1.02 [95% CI, 0.83-1.27]), or hydroxychloroquine with azithromycin (HR, 0.98 [95% CI, 0.75-1.28]). The 30-day unadjusted mortality for patients receiving hydroxychloroquine alone, azithromycin alone, the combination or neither drug was 25%, 20%, 18%, and 20%, respectively. Among 547 evaluable ICU patients, including 134 receiving tocilizumab in the ICU, an exploratory analysis found a trend towards an improved survival association with tocilizumab treatment (adjusted HR, 0.76 [95% CI, 0.57-1.00]), with 30 day unadjusted mortality with and without tocilizumab of 46% versus 56%.ConclusionsThis observational cohort study suggests hydroxychloroquine, either alone or in combination with azithromycin, was not associated with a survival benefit among hospitalized COVID-19 patients. Tocilizumab demonstrated a trend association towards reduced mortality among ICU patients. Our findings are limited to hospitalized patients and must be interpreted with caution while awaiting results of randomized trials.Trial RegistrationClinicaltrials.gov Identifier: NCT04347993