Trial Evaluating Ambulatory Treatment of Travelers' Diarrhea (TrEAT TD)

• Clinical Cure - Acute Watery Diarrhea group [ Time Frame: 24 hours ] [ Designated as safety issue: No ]
  • No grade 3-5 stools beyond 24 hours after initiation of therapy meeting diarrhea definition (≥3 loose or liquid stools in 24 hour period). All diarrhea associated symptoms present must be no greater than mild in severity and have no impact on activity.

  • AND, no treatment failure events to include the following:

    • Recurrence of diarrheal illness meeting case definition of TD occurring within 72 hours after clinical cure
    • Worsening of, or failure to improve, clinical symptoms after 24 hours of therapy
    • Illness continuing after 72 hours
  
  
• Clinical Cure - Acute Dysentery/Febrile Diarrhea group [ Time Frame: 48 hours ] [ Designated as safety issue: No ]
  • No grade 3-5 stools beyond 48 hours after initiation of therapy meeting diarrhea definition (≥3 loose or liquid stools in 24 hour period) and resolution of acute dysentery/febrile diarrhea-associated signs/symptoms to include fever and gross blood in stool, as well as report of no impact on activity

  • AND, no treatment failure events to include the following:

    • Recurrence of diarrheal illness meeting case definition of TD occurring within 72 hours after clinical cure
    • Worsening of, or failure to improve after 24 hours of therapy
    • Illness continuing after 72 hours
  
  

• Time to Last Unformed Stool [ Time Frame: 24, 48, 72 hours ] [ Designated as safety issue: No ]
  Calculated as the time from taking the first dose of study medication until passage of the last unformed stool that meets diarrhea definition (grade 3-5 stool associated with 2 other loose stools in 24 hours or 1 other loose stool and associated symptoms in that same 24 hour block) after which subjects are declared well. Where, last unformed stool = last grade 3-5 stool occurring in a 24-hr period meeting the diarrhea definition.
  
  

The study will be a multi-site, randomized, double-blind, controlled clinical trial among ambulatory deployed personnel. Patients presenting for care will be clinically assessed and a determination made as to whether they have acute watery diarrhea (AWD) or acute dysentery/febrile diarrhea (ADF). For the AWD arm, patients will be randomized to receive 1 of 3 regimens: (1) rifaximin 1650 mg as a single dose plus loperamide 4 mg initially followed by 2 mg after each unformed stool, not to exceed 16 mg/day for 2 days (120 subjects); (2) azithromycin 500 mg as a single dose plus loperamide 4 mg initially followed by 2 mg after each unformed stool, not to exceed 16 mg/day for 2 days (120 subjects); or (3) levofloxacin 500 mg as a single dose plus loperamide 4 mg initially followed by 2 mg after each unformed stool, not to exceed 16 mg/day for 2 days (120 subjects).

For the ADF arm, patients will be randomized to receive 1 of 2 regimens: (1) azithromycin 1000 mg as a single dose plus loperamide 4 mg initially followed by 2 mg after each unformed stool, not to exceed 16 mg/day for 2 days (75 subjects); or (2) azithromycin 1000 mg as a single dose without loperamide (75 subjects).

Study Procedures (Brief): Baseline exam as well as blood and stool samples will be collected at initial clinic visit. Clinical assessments will be performed at 24 hours, 72 hours, and 7 days. In addition, microbiological cure will be evaluated at 7-d post initiation of treatment. Subjects will have blood drawn to assess for serological conversion to common enteric pathogens, and stool collected at 7- and 21-d . Subjects may also opt in for long-term follow-up at time of enrollment, which will assess for development of post-infectious functional bowel disorders. All subjects will complete a baseline assessment at 7-d visit, and those who opt for the additional follow-up will complete a series of web-based surveys at 3-, 6-, 9-, and 12-m post enrollment.