Pathogenesis-based preexposure prophylaxis associated with a low risk of SARS-CoV-2 infection in healthcare workers at a designated COVID-19 hospital: a pilot study

BMC Infect Dis. 2021 Jun 7;21(1):536. doi: 10.1186/s12879-021-06241-1.


Background: At present, no agents are known to be effective at preventing COVID-19. Based on current knowledge of the pathogenesis of this disease, we suggest that SARS-CoV-2 infection might be attenuated by directly maintaining innate pulmonary redox, metabolic and dilation functions using well-tolerated medications that are known to serve these functions, specifically, a low-dose aerosolized combination of glutathione, inosine and potassium.

Methods: From June 1 to July 10, 2020, we conducted a pilot, prospective, open-label, single-arm, single-center study to evaluate the safety and efficacy of preexposure prophylaxis (PrEP) with aerosolized combination medication (ACM) on the incidence of SARS-CoV-2 positivity in 99 healthcare workers (HCWs) at a hospital designated for treating COVID-19 patients. We compared SARS-CoV-2 positivity in ACM users to retrospective data collected from 268 untreated HCWs at the same hospital. Eligible participants received an aerosolized combination of 21.3 mg/ml glutathione and 8.7 mg/ml inosine in 107 mM potassium solution for 14 days. The main outcome was the frequency of laboratory-confirmed SARS-CoV-2 cases, defined as individuals with positive genetic or immunological tests within 28 days of the study period.

Results: SARS-CoV-2 was detected in 2 ACM users (2, 95% CI: 0.3 to 7.1%), which was significantly less than the incidence in nonusers, at 24 (9, 95% CI: 5.8 to 13.0%; P = 0.02). During the PrEP period, solicited adverse events occurred in five participants; all were mild and transient reactions.

Conclusions: Our findings might be used either to prevent SARS-CoV-2 infection or to support ongoing and new research into more effective treatments for COVID-19.

Trial registration: ISRCTN, ISRCTN34160010 . Registered 14 September 2020 - Retrospectively registered.

Keywords: COVID-19; Coronavirus disease; PrEP; Preexposure prophylaxis; SARS-CoV-2.

MeSH terms

  • Adult
  • Aerosols / pharmacology
  • COVID-19 / prevention & control*
  • COVID-19 Drug Treatment*
  • Female
  • Health Personnel*
  • Hospitals
  • Humans
  • Longitudinal Studies
  • Male
  • Middle Aged
  • Pilot Projects
  • Pre-Exposure Prophylaxis*
  • Prospective Studies
  • Retrospective Studies
  • Treatment Outcome


  • Aerosols