Antimalarials are not Effective as Pre-Exposure Prophylaxis for COVID-19: A Retrospective Matched Control Study

August 2023 | Volume 22 | Issue 8 | 840 | Copyright © August 2023


Published online July 31, 2023

Nikolai Klebanov MDa,b*, Vartan Pahalyants MD MBAa,b,c*, Jordan T. Said MDa,b, William. S. Murphy MD MBAa,b,c, Nicholas Theodosakis MD PhDa,b, Joseph Scarry MA, Stacey Duey d, Monina Klevens DDSe, Evelyn Lilly MDa^, Yevgeniy R. Semenov MD MAa^

aMassachusetts General Hospital, Boston, MA 
bHarvard Medical School, Boston, MA 
cHarvard Business School, Boston, MA 
dDivision of Research Information Science and Computing, Mass General Brigham, Boston, MA 
eMassachusetts Department of Public Health, Bureau of Infectious Disease, and Laboratory Sciences, Boston, MA

* These authors contributed equally to this manuscript. 
^ These authors contributed equally to this manuscript.

independently significantly associated with a lower risk for SARS-CoV-2 infection. Given that the treatment of rheumatic disease and hematologic/metastatic malignancy - with systemic immunosuppression and chemotherapy, respectively - can plausibly reduce the immune response to SARS-CoV-2, patients with a history of these diseases may engage in protective behaviors to limit their potential exposure to infection, as has been reported amongst patients with rheumatic diseases.7,8 

Limitations include Massachusetts-restricted data and a single-center perspective. Study patients who were prescribed antimalarials were more likely to live in zip codes with lower COVID-19 incidence rates and higher average incomes, which may be confounded by differential access to care.

Antimalarial agents - particularly hydroxychloroquine - received significant consideration as a potential treatment for or prophylactic drug against COVID-19.2 We demonstrate that, amongst patients with antimalarial prescriptions predating the COVID-19 pandemic in Massachusetts, antimalarials did not significantly prevent SARS-CoV-2 infection. These findings corroborate that hydroxychloroquine and related antimalarials do not have a role in protection against SARS-CoV-2.

DISCLOSURES

The authors above have no conflicts of interest to disclose for the following work.

IRB approval status: This study was approved by the Institutional Review Boards at Mass General Brigham (Protocol 2020P001191) and Massachusetts Department of Public Health (Protocol 1606024-2).

Funding: This work was conducted with support from Harvard Catalyst, The Harvard Clinical and Translational Science Center (BR; National Center for Research Resources and the National Center for Advancing Translational Sciences, National Institutes of Health Award UL1 TR001102), and financial contributions from Harvard University and its affiliated academic healthcare centers.

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AUTHOR CORRESPONDENCE

Yevgeniy R. Semenov MD MA ysemenov@mgh.harvard.edu
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