A Randomized Controlled Trial of Hydroxychloroquine as Prophylaxis for COVID-19 among Health Care Providers

Ramin Parvizrad1, Ghasem Mosayebi2, Nader Zarinfar3, Morteza Mousavi-Hasanzadeh4, Seyedeh Zahra Razavi5, Somayeh Nikfar6, Amir Almasi-Hashiani7, *
1 Department of Emergency Medicine, Arak University of Medical Sciences,, Arak, Iran
2 Department of Immunology, Arak University of Medical Sciences, Arak, Iran
3 Department of Infectious Diseases, Arak University of Medical Sciences, Arak, Iran
4 Student Research Committee, Arak University of Medical Sciences, Arak, Iran
5 Zanjan University of Medical Sciences, Zanjan, Iran
6 Department of Obstetrics and Gynecology, Arak University of Medical Sciences, Arak, Iran
7 Department of Epidemiology, Arak University of Medical Sciences, Arak, Iran

Article Metrics

CrossRef Citations:
Total Statistics:

Full-Text HTML Views: 184
Abstract HTML Views: 110
PDF Downloads: 96
Total Views/Downloads: 390
Unique Statistics:

Full-Text HTML Views: 150
Abstract HTML Views: 81
PDF Downloads: 83
Total Views/Downloads: 314

Creative Commons License
© 2021 Almasi-Hashiani et al.

open-access license: This is an open access article distributed under the terms of the Creative Commons Attribution 4.0 International Public License (CC-BY 4.0), a copy of which is available at: This license permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

* Address correspondence to this author at Department of Epidemiology, Arak University of Medical Sciences, Arak, Iran; E-mail:



Although there is a growing consensus that hydroxychloroquine may not be effective in the treatment of COVID-19 patients, there is still little high-quality evidence about the prophylactic effects of this medication. In this study, we aimed to evaluate the efficiency of hydroxychloroquine in preventing COVID-19 infection among healthcare workers.


In this clinical trial, 90 healthcare providers from two referral hospitals of COVID-19 were divided into the hydroxychloroquine group (400 mg/week for eight weeks) and the routine-care group. Serum CRP levels and the frequency of T-helper (CD4+ cells) and T-cytotoxic (CD8+ cells) were assessed at the beginning and end of the study. The groups were compared in terms of White Blood cells (WBCs), polymorph nuclear cells (PMNs), lymphocytes (LYM), hemoglobin (Hb), and platelets (Plt.).


The results revealed no significant differences between the two groups in terms of WBC, PMN, LYM, Hb, Plt., CD4, and CD8. The mean difference of the CD4:CD8 ratio showed a significantly higher decrease (P=0.05) in hydroxychloroquine group than in the control group (0.18 vs. 0.02). The incidence of COVID-19 was 15% (95%CI: 12-18%) in the control group and 10% (95%CI: 8-12%) in the intervention group; however, no significant difference was observed between the two groups in this regard (P=0.45).


Our study findings boost an increasing level of evidence that hydroxychloroquine is not an effective prophylactic medication against COVID-19 and might even exacerbate the profile of pandemic containment efforts by adding more pain to patients’ life and healthcare services.

Keywords: Hydroxychloroquine, Prophylaxis, COVID-19, Healthcare providers, Clinical trial, Participants.