A Phase 3 interventional study of Ondansetron Oral Solution and Oral Placebo in Acute Gastroenteritis, Viral Illness and Vomiting, sponsored by University of Calgary. Completed at 6 sites in Canada. Open to participants aged 6 Months to 17 Years. Per ClinicalTrials.gov, last updated 2025-04-25.
Sponsored by University of Calgary · Phase 3, Interventional, and Treatment
A phase III, double-blind, parallel-design, randomized, placebo-controlled trial to compare multi-dose oral Ondansetron with placebo as treatment for vomiting secondary to acute gastroenteritis (AGE), after Emergency Department discharge.
The annual burden of acute gastroenteritis in the United States includes 17 million related episodes and 473,832 hospitalizations. Although oral-rehydration therapy is recommended for children with mild-to-moderate dehydration, it has historically been underused with emergency department (ED) clinicians being more likely to choose intravenous over oral rehydration especially when vomiting is a major symptom. In fact, nearly 95% of children undergoing oral rehydration in Canadian EDs present with recent vomiting. To address this issue, the investigators conducted both a landmark clinical trial and a recent meta-analysis that have demonstrated that the ED use of ondansetron, an anti-emetic, leads to reductions in intravenous rehydration and hospitalization and is cost-effective. However, the available data revealed some associations with increased diarrhea and no evidence of benefits associated with ongoing ondansetron use following ED discharge. Despite the lack of available data, the provision of multiple doses of ondansetron for home use has become routine in many EDs across North America. The literature has differing opinions on the topic of ongoing ondansetron use after ED discharge and given the limited evidence supporting its use, the potential side effects and additional cost, there is an urgent need to definitively evaluate the effect of multiple doses of ondansetron in children, focusing on family-centred, post-index visit outcomes.
A phase III, double-blind, parallel-design, randomized, placebo controlled trial to compare multi-dose oral Ondansetron with placebo as treatment for vomiting secondary to acute gastroenteritis (AGE), after Emergency Department discharge will be conducted. Children and youth, age 6 months to 17.99 years will be enrolled at six (6) Canadian Emergency Departments. The total number of participants recruited will be 1030. Participants will be enrolled at six (6) pediatric emergency departments across Canada.
Children who are provided a minimum of one dose of ondansetron as part of their routine clinical care AND meet other eligibility criteria will be randomized to receive an at-home kit with six (6) doses of Ondansetron Hydrochloride Dihydrate Oral Solution (4mg/5mL solution; dosed at 0.15mg/kg to a maximum single dose of 8mg) or equivalent volume in a Placebo Oral Solution to be administered no sooner than 8 hours after the initial clinical dose was provided by the ED physician. Over the subsequent 48 hours, the study intervention will be administered at a rate of 1 dose every 8 hours (q8h) to a maximum of 3 doses a day (in a 24-hour period (TID)) at the caregiver's discretion. Two (2) additional doses will be provided to the caregiver in case the child vomits a dose.
656 studies on the registry are indexed under Virus Diseases; 85 are open to participants now.
This study's enrollment of 1,030 is above the median of 100 across 464 interventional studies indexed under Virus Diseases.
Browse Virus Diseases studies →University of Calgary is the lead sponsor of 703 studies on the registry; 196 are open to participants now.
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Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
On an ECG, the QT interval is the time the heart’s lower chambers take to activate electrically and recover in each beat. QTc is that time adjusted for heart rate (QTcF by Fridericia’s formula, QTcB by Bazett’s). Some medicines lengthen it, and a long QTc can raise the risk of a dangerous heart rhythm.
The study may name a correction formula and a limit in milliseconds, often around 450–480.
Hypersensitivity
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
QT and QTc
On an ECG, the QT interval is the time the heart’s lower chambers take to activate electrically and recover in each beat. QTc is that time adjusted for heart rate (QTcF by Fridericia’s formula, QTcB by Bazett’s). Some medicines lengthen it, and a long QTc can raise the risk of a dangerous heart rhythm.
The study may name a correction formula and a limit in milliseconds, often around 450–480.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Ondansetron Oral Solution (4mg/5mL solution) - Dose = 0.15mg/kg. One dose every 8 hours (q8h), as needed. Up to a maximum of six doses over 48 hours.
Drug: Ondansetron Oral Solution
Compounded Placebo Oral Solution to match experimental arm
Drug: Oral Placebo
Six doses of oral ondansetron (0.15mg/kg) to be administered q8h (every 8 hours) to a maximum of 3 times in a 24 hour period, are provided to the participant/caregiver for use after emergency department disposition (i.e. home use), as needed.
Also known as: Zofran
Six doses of oral placebo (0.15mg/kg) to be administered q8h (every 8 hours) to a maximum of 3 times in a 24-hour period, are provided to the participant/caregiver for use after emergency department disposition (i.e. home use), as needed.
Development of moderate to severe disease as defined by the Modified Vesikari Scale (MVS) Score of ≥ 9 following ED evaluation - change in the MVS score between Hour 0 and Hour 168 of the study.
The Modified Vesikari Scale Score (MVS) is a composite measure which includes several variables representing the severity of disease - points are summed to provide an overall score: * Duration of diarrhea (hours): 0 (0 points), 1-96 (1 point), 97-120 (2 points), ≥121 (3 points) * Maximum number of watery stools per 24 hour period: 0 (0 points), 1-3 (1 point), 4-5 (2 points), ≥6 (3 points) * Duration of vomiting (hours): 0 (0 points), 1-24 (1 point), 25-48 (2 points), ≥49 (3 points) * Maximum number of vomiting episodes per 24 hour period: none (0 points), 1 (1 point), 2-3 (2 points), ≥5 (3 points). * Maximum recorded rectal temperature (degrees Celsius): \<37.0 (0 points), 37.1-38.4 (1 point), 38.5-38.9 (2 points), ≥39.0 (3 points) * Unscheduled health care visit: None (0 points), Primary Care (2 points), emergency department (3 points) * Treatment: None (0 points), Rehydration with IV fluids (1 point), Hospitalization (2 points)
Time frame: Measured 24, 48, and 168 hours after baseline visit
Vomiting Duration
Number of hours of vomiting following ED disposition.
Time frame: Measured 24, 48, and 168 hours after baseline visit
Vomiting Frequency
Number of episodes of vomiting following ED disposition.
Time frame: Measured 24, 48, and 168 hours after baseline visit
Vomiting Proportion
The proportion who experience vomiting following ED disposition.
Time frame: Measured 24, 48, and 168 hours after baseline visit
Proportion of participants who require an unscheduled health care visit
Unscheduled health care provider visits following Emergency Department disposition. Is there a difference in the proportion who require an unscheduled health care provider visit following ED disposition.
Time frame: Measured 24, 48, and 168 hours after baseline visit
Proportion of participants who require Intravenous (IV) Rehydration
Is there a difference in the proportion who require intravenous rehydration following ED disposition.
Time frame: Measured 24, 48, and 168 hours after baseline visit
Satisfaction with care: 5 point Likert Scale
Caregivers will be asked about their level of satisfaction with the therapy provided measured on the following 5 point Likert scale (choose one option): * 1 - Very dissatisfied * 2 - Dissatisfied * 3 - Neither satisfied, nor dissatisfied * 4 - Satisfied * 5 - Very Satisfied
Time frame: 168 hours after baseline
Safety Profile of Multiple Doses of Oral Ondansetron
To determine if the discharge of children with AGE associated vomiting who are administered ondansetron in the ED with additional doses to be taken at home is associated with adverse events (e.g. diarrhea, revisits) as compared with placebo.
Time frame: Measured 24, 48, and 168 hours after baseline visit
Plan to share: Undecided
This study is completed, as verified in Apr 2025. You cannot join it, but the record below documents what was studied.
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Studies of the drug tested here: Ondansetron