Efficacy and Safety of Nitazoxanide in Addition to Standard of Care for the Treatment of Severe Acute Respiratory Illness

Clin Infect Dis. 2019 Nov 13;69(11):1903-1911. doi: 10.1093/cid/ciz100.


Background: Effective therapeutics for respiratory viruses are needed. Early data suggest that nitazoxanide (NTZ) may be beneficial for treating acute respiratory viral illness.

Methods: From March 2014 through March 2017, a double-blind, placebo-controlled trial was conducted in 260 participants ≥1 year old hospitalized with influenza-like illness at 6 hospitals in Mexico. Participants were randomized 1:1 to NTZ (age ≥12 years, 600 mg twice daily; age 4-11 years and 1-3 years, 200 or 100 mg twice daily, respectively) or placebo for 5 days in addition to standard of care. The primary endpoint was time from first dose to hospital discharge. Influenza reverse-transcription polymerase chain reaction and Respifinder 22 multiplex test were used for virus detection.

Results: Of 260 participants enrolled, 257 were randomized and took at least 1 dose of study treatment (intention-to-treat population): 130 in the NTZ group and 127 in the placebo group. The Kaplan-Meier estimate of the median duration of hospitalization was 6.5 (interquartile range [IQR], 4.0-9.0) days in the NTZ group vs 7.0 (IQR, 4.0-9.0) days in the placebo group (P = .56). Duration of hospitalization between the 2 treatments was similar in children (P = .29) and adults (P = .62), influenza A and B (P = .32), and other respiratory viruses. Seven (5.4%) and 6 (4.7%) participants in the NTZ and placebo groups, respectively, reported serious adverse events.

Conclusions: Treatment with NTZ did not reduce the duration of hospital stay in severe influenza-like illness. Further analyses based on age and evaluations by virus did not reveal any subgroups that appeared to benefit from NTZ.

Clinical trials registration: NCT02057757.

Keywords: hospitalized; influenza-like illness; nitazoxanide; respiratory virus.

Publication types

  • Randomized Controlled Trial
  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Antiviral Agents / adverse effects
  • Antiviral Agents / therapeutic use*
  • Child
  • Child, Preschool
  • Double-Blind Method
  • Female
  • Hospitalization
  • Humans
  • Kaplan-Meier Estimate
  • Male
  • Middle Aged
  • Nitro Compounds
  • Oseltamivir / adverse effects
  • Oseltamivir / therapeutic use
  • Severe Acute Respiratory Syndrome / drug therapy*
  • Severe Acute Respiratory Syndrome / virology
  • Thiazoles / adverse effects
  • Thiazoles / therapeutic use*
  • Treatment Outcome
  • Young Adult
  • Zanamivir / adverse effects
  • Zanamivir / therapeutic use


  • Antiviral Agents
  • Nitro Compounds
  • Thiazoles
  • Oseltamivir
  • Zanamivir
  • nitazoxanide

Associated data

  • ClinicalTrials.gov/NCT02057757