Rifaximin Fails to Prevent Campylobacteriosis in the Human Challenge Model: A Randomized, Double-Blind, Placebo-Controlled Trial

Clin Infect Dis. 2018 Apr 17;66(9):1435-1441. doi: 10.1093/cid/cix1014.


Background: Campylobacter species are a leading cause of diarrheal disease globally with significant morbidity. Primary prevention efforts have yielded limited results. Rifaximin chemoprophylaxis decreases rates of travelers' diarrhea and may be suitable for high-risk persons. We assessed the efficacy of rifaximin in the controlled human infection model for Campylobacter jejuni.

Methods: Twenty-eight subjects were admitted to an inpatient facility and randomized to a twice-daily dose of 550 mg rifaximin or placebo. The following day, subjects ingested 1.7 × 105 colony-forming units of C. jejuni strain CG8421. Subjects continued prophylaxis for 3 additional days, were followed for campylobacteriosis for 144 hours, and were subsequently treated with azithromycin and ciprofloxacin. Samples were collected to assess immunologic responses to CG8421.

Results: There was no difference (P = 1.0) in the frequency of campylobacteriosis in those receiving rifaximin (86.7%) or placebo (84.6%). Additionally, there were no differences in the clinical signs and symptoms of C. jejuni infection to include abdominal pain/cramps (P = 1.0), nausea (P = 1.0), vomiting (P = .2), or fever (P = 1.0) across study groups. Immune responses to the CG8421 strain were comparable across treatment groups.

Conclusions: Rifaximin did not prevent campylobacteriosis in this controlled human infection model. Given the morbidity associated with Campylobacter infection, primary prevention efforts remain a significant need.

Clinical trials registration: NCT02280044.

Publication types

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

MeSH terms

  • Adult
  • Anti-Bacterial Agents / administration & dosage
  • Anti-Bacterial Agents / therapeutic use*
  • Azithromycin / therapeutic use
  • Campylobacter Infections / prevention & control*
  • Campylobacter jejuni
  • Chemoprevention*
  • Ciprofloxacin / therapeutic use
  • Diarrhea / prevention & control
  • Double-Blind Method
  • Female
  • Healthy Volunteers
  • Human Experimentation
  • Humans
  • Male
  • Rifaximin / administration & dosage
  • Rifaximin / therapeutic use*
  • Young Adult


  • Anti-Bacterial Agents
  • Ciprofloxacin
  • Azithromycin
  • Rifaximin

Associated data

  • ClinicalTrials.gov/NCT02280044