Trial Outcomes & Findings for AZithromycin Therapy in Preschoolers With a Severe Wheezing Episode Diagnosed at the Emergency Department (NCT NCT04669288)

NCT ID: NCT04669288

Last Updated: 2026-06-23

Results Overview

The Asthma Flare-up Diary for Young Children (ADYC) is a validated instrument that consists of a 17-item questionnaire scored from 1 (best) to 7 (worst). The parent or guardian of the enrolled child (up to 60 months of age) filled out the diary daily for 5 days, starting from the first day following the first dose of Azithromycin (AZ). The cumulative score at the end of 5 days was used to assess response to the intervention (e.g. time to exacerbation, acute-care visit, hospitalization and no wheeze), with a higher score indicating a worse outcome. For each of the five follow-up days, the ADYC score was calculated as the average score per question and the trial primary outcome was the sum of these ADYC scores over the five days. The range of possible primary outcome values was a ADYC score of 5 to 35.

Recruitment status

TERMINATED

Study phase

PHASE3

Target enrollment

840 participants

Primary outcome timeframe

5 day course of azithromycin

Results posted on

2026-06-23

Participant Flow

Patients aged 18 to 59 months of age and presenting in the emergency department with an episode of wheezing that was moderate/severe by clinical score (PRAM score of greater than or equal to 4). The first participant was enrolled 22-November-2021. The last participant was enrolled 10-December-2024 when enrollment was stopped by the Data Safety Monitoring Board based interim analysis futility.

Of the 840 enrolled participants, 833 were randomized into one of the two study arms and were tested for pathogenic bacteria.

Participant milestones

Participant milestones
Measure
Treatment - Active (Azithromycin)
Participants received 12 mg/kg dose per day of oral azithromycin for 5 days. The first dose of the study medication was administered before discharge from the ED. Remaining study azithromycin was given to parents to administer at home for 4 subsequent days. Azithromycin oral suspension
Treatment - Placebo
Participants received 12 mg/kg dose per day of oral placebo for 5 days. The first dose of the study azithromycin-placebo liquid was administered orally before discharge from the ED. Remaining azithromycin-placebo was given to parents to administer at home for 4 subsequent days. Placebo: Azithromycin placebo, oral suspension.
Overall Study
STARTED
415
418
Overall Study
Bacterial
257
264
Overall Study
Non-Bacterial
158
154
Overall Study
COMPLETED
408
404
Overall Study
NOT COMPLETED
7
14

Reasons for withdrawal

Withdrawal data not reported

Baseline Characteristics

Subjects are separated by treatment arm and by bacterial designation. Together, the rows equal the total number of participants analyzed.

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure
Treatment - Active (Azithromycin)
n=413 NP Swab Positive Viruses
Aged 18-60 months of age (mo). Separated by positive for bacterial infection and negative for bacterial infection.
Treatment - Placebo
n=417 NP Swab Positive Viruses
Aged 18-60 months of age (mo). Separated by positive for bacterial infection and negative for bacterial infection.
Total
n=830 NP Swab Positive Viruses
Total of all reporting groups
Age, Customized
18 to <24 Months
62 Participants
n=415 Participants
80 Participants
n=418 Participants
142 Participants
n=833 Participants
Age, Customized
24 to <36 Months
142 Participants
n=415 Participants
135 Participants
n=418 Participants
277 Participants
n=833 Participants
Age, Customized
36 to <48 Months
123 Participants
n=415 Participants
117 Participants
n=418 Participants
240 Participants
n=833 Participants
Age, Customized
48 to <60 Months
88 Participants
n=415 Participants
86 Participants
n=418 Participants
174 Participants
n=833 Participants
Sex: Female, Male
Female
158 Participants
n=415 Participants
163 Participants
n=418 Participants
321 Participants
n=833 Participants
Sex: Female, Male
Male
257 Participants
n=415 Participants
255 Participants
n=418 Participants
512 Participants
n=833 Participants
Race (NIH/OMB)
American Indian or Alaska Native
2 Participants
n=415 Participants
1 Participants
n=418 Participants
3 Participants
n=833 Participants
Race (NIH/OMB)
Asian
7 Participants
n=415 Participants
5 Participants
n=418 Participants
12 Participants
n=833 Participants
Race (NIH/OMB)
Native Hawaiian or Other Pacific Islander
193 Participants
n=415 Participants
204 Participants
n=418 Participants
397 Participants
n=833 Participants
Race (NIH/OMB)
Black or African American
2 Participants
n=415 Participants
0 Participants
n=418 Participants
2 Participants
n=833 Participants
Race (NIH/OMB)
White
142 Participants
n=415 Participants
138 Participants
n=418 Participants
280 Participants
n=833 Participants
Race (NIH/OMB)
More than one race
22 Participants
n=415 Participants
20 Participants
n=418 Participants
42 Participants
n=833 Participants
Race (NIH/OMB)
Unknown or Not Reported
47 Participants
n=415 Participants
50 Participants
n=418 Participants
97 Participants
n=833 Participants
Ethnicity (NIH/OMB)
Hispanic or Latino
77 Participants
n=415 Participants
88 Participants
n=418 Participants
165 Participants
n=833 Participants
Ethnicity (NIH/OMB)
Not Hispanic or Latino
330 Participants
n=415 Participants
322 Participants
n=418 Participants
652 Participants
n=833 Participants
Ethnicity (NIH/OMB)
Unknown or Not Reported
8 Participants
n=415 Participants
8 Participants
n=418 Participants
16 Participants
n=833 Participants
Hospitalization
Hospitalized
200 Participants
n=415 Participants
216 Participants
n=418 Participants
416 Participants
n=833 Participants
Hospitalization
Not Hospitalized
215 Participants
n=415 Participants
202 Participants
n=418 Participants
417 Participants
n=833 Participants
Antibiotics in the ED
Subject took other antibiotics in the ED
7 Participants
n=415 Participants
5 Participants
n=418 Participants
12 Participants
n=833 Participants
Antibiotics in the ED
No other antibiotics taken in ED
408 Participants
n=415 Participants
413 Participants
n=418 Participants
821 Participants
n=833 Participants
Pediatric Respiratory Assessment Measure (PRAM)
Bacterial
6.0 scored on a range
STANDARD_DEVIATION 1.78 • n=257 Participants • Subjects are separated by treatment arm and by bacterial designation. Together, the rows equal the total number of participants analyzed.
6.2 scored on a range
STANDARD_DEVIATION 1.81 • n=264 Participants • Subjects are separated by treatment arm and by bacterial designation. Together, the rows equal the total number of participants analyzed.
6.1 scored on a range
STANDARD_DEVIATION 1.80 • n=521 Participants • Subjects are separated by treatment arm and by bacterial designation. Together, the rows equal the total number of participants analyzed.
Pediatric Respiratory Assessment Measure (PRAM)
Non-Bacterial
6.5 scored on a range
STANDARD_DEVIATION 1.91 • n=158 Participants • Subjects are separated by treatment arm and by bacterial designation. Together, the rows equal the total number of participants analyzed.
6.6 scored on a range
STANDARD_DEVIATION 1.97 • n=154 Participants • Subjects are separated by treatment arm and by bacterial designation. Together, the rows equal the total number of participants analyzed.
6.5 scored on a range
STANDARD_DEVIATION 1.94 • n=312 Participants • Subjects are separated by treatment arm and by bacterial designation. Together, the rows equal the total number of participants analyzed.
PRAM Score By Range
PRAM Score Range: 5-7
318 Participants
n=415 Participants
319 Participants
n=418 Participants
637 Participants
n=833 Participants
PRAM Score By Range
PRAM Score Range: 8-12
97 Participants
n=415 Participants
99 Participants
n=418 Participants
196 Participants
n=833 Participants
NP Swab Viral Results
Viral Positive
352 Participants
n=415 Participants
365 Participants
n=418 Participants
717 Participants
n=833 Participants
NP Swab Viral Results
Viral Negative
63 Participants
n=415 Participants
53 Participants
n=418 Participants
116 Participants
n=833 Participants
NP Swab Positive for Viruses
Human Rhinovirus (HRV) Results
292 NP Swab Positive Viruses
n=413 NP Swab Positive Viruses
312 NP Swab Positive Viruses
n=417 NP Swab Positive Viruses
604 NP Swab Positive Viruses
n=830 NP Swab Positive Viruses
NP Swab Positive for Viruses
Human Respiratory Syncytial Virus (RSV) Results
37 NP Swab Positive Viruses
n=413 NP Swab Positive Viruses
40 NP Swab Positive Viruses
n=417 NP Swab Positive Viruses
77 NP Swab Positive Viruses
n=830 NP Swab Positive Viruses
NP Swab Positive for Viruses
Bocavirus (HBoV) Results
24 NP Swab Positive Viruses
n=413 NP Swab Positive Viruses
14 NP Swab Positive Viruses
n=417 NP Swab Positive Viruses
38 NP Swab Positive Viruses
n=830 NP Swab Positive Viruses
NP Swab Positive for Viruses
Human Metapneumovirus (hMPV) Results
20 NP Swab Positive Viruses
n=413 NP Swab Positive Viruses
11 NP Swab Positive Viruses
n=417 NP Swab Positive Viruses
31 NP Swab Positive Viruses
n=830 NP Swab Positive Viruses
NP Swab Positive for Viruses
Human Parainfluenza (HPIV) Results
11 NP Swab Positive Viruses
n=413 NP Swab Positive Viruses
13 NP Swab Positive Viruses
n=417 NP Swab Positive Viruses
24 NP Swab Positive Viruses
n=830 NP Swab Positive Viruses
NP Swab Positive for Viruses
Any other combination of viruses (Other) Results
29 NP Swab Positive Viruses
n=413 NP Swab Positive Viruses
27 NP Swab Positive Viruses
n=417 NP Swab Positive Viruses
56 NP Swab Positive Viruses
n=830 NP Swab Positive Viruses

PRIMARY outcome

Timeframe: 5 day course of azithromycin

Population: ADYC surveys were completed for assessment using imputation

The Asthma Flare-up Diary for Young Children (ADYC) is a validated instrument that consists of a 17-item questionnaire scored from 1 (best) to 7 (worst). The parent or guardian of the enrolled child (up to 60 months of age) filled out the diary daily for 5 days, starting from the first day following the first dose of Azithromycin (AZ). The cumulative score at the end of 5 days was used to assess response to the intervention (e.g. time to exacerbation, acute-care visit, hospitalization and no wheeze), with a higher score indicating a worse outcome. For each of the five follow-up days, the ADYC score was calculated as the average score per question and the trial primary outcome was the sum of these ADYC scores over the five days. The range of possible primary outcome values was a ADYC score of 5 to 35.

Outcome measures

Outcome measures
Measure
Treatment: Placebo
n=418 Participants
Eligible participants who were hospitalized during treatment
Treatment: Azithromycin
n=415 Participants
Eligible participants who returned to the ED or were hospitalized within 72 hours following randomization
ADYC (Median, IQR)
Non-Bacterial
9.10 Scored on a scale
Interval 7.19 to 11.45
9.30 Scored on a scale
Interval 6.97 to 11.62
ADYC (Median, IQR)
Bacterial
9.72 Scored on a scale
Interval 7.66 to 12.17
9.59 Scored on a scale
Interval 7.29 to 12.6

SECONDARY outcome

Timeframe: From admission at ED to discharge from ED, up to 23 hours and 59 minutes

Population: The Length of Stay (LOS) measurement is assessed on all 833 participants randomized in the ED

The continuous secondary variable of length of stay was analyzed in the same manner as the primary outcome. The measurement is the duration from arrival to ED to discharge. Subjects are separated by treatment arm and by bacterial designation. Together, the rows equal the total number of participants analyzed.

Outcome measures

Outcome measures
Measure
Treatment: Placebo
n=418 Participants
Eligible participants who were hospitalized during treatment
Treatment: Azithromycin
n=415 Participants
Eligible participants who returned to the ED or were hospitalized within 72 hours following randomization
ED Length of Stay (Median, IQR)
Bacterial
4.9 Hours of stay at the ED
Interval 3.9 to 7.0
5.2 Hours of stay at the ED
Interval 4.1 to 6.8
ED Length of Stay (Median, IQR)
Non-Bacterial
4.9 Hours of stay at the ED
Interval 3.8 to 6.4
4.9 Hours of stay at the ED
Interval 3.9 to 6.2

SECONDARY outcome

Timeframe: From hospital admission to discharge from hospital

Population: Length of hospitalization in hours was measured in all children. One patient, from the Placebo-Bacterial group had missing length of stay.

The continuous secondary variable of length of stay was analyzed in the same manner as the primary outcome. The measurement is the duration of hospitalization from admission. Subjects are separated by treatment arm and by bacterial designation. Together, the rows equal the total number of participants analyzed.

Outcome measures

Outcome measures
Measure
Treatment: Placebo
n=418 Participants
Eligible participants who were hospitalized during treatment
Treatment: Azithromycin
n=415 Participants
Eligible participants who returned to the ED or were hospitalized within 72 hours following randomization
Hospital Length of Stay (Median, IQR)
Bacterial
15.8 Hours of stay after hospitalization
Interval 4.3 to 29.6
7.7 Hours of stay after hospitalization
Interval 4.5 to 28.4
Hospital Length of Stay (Median, IQR)
Non-Bacterial
16.9 Hours of stay after hospitalization
Interval 4.3 to 29.5
13.1 Hours of stay after hospitalization
Interval 4.3 to 29.5

SECONDARY outcome

Timeframe: Within 72 hours after randomization

Population: Subjects are separated by treatment arm and by bacterial designation. Together, the rows equal the total number of participants analyzed.

Visits to the ED or hospital within 72 hours of the initial visit (randomization time) are counted as a revisit outcome. This outcome was tabulated by treatment for each stratum (site and baseline severity of symptoms). The dichotomous outcome of the second ED visit or hospitalization is compared using a Mantel-Haenszel chi-square test, stratified by clinical center and baseline severity.

Outcome measures

Outcome measures
Measure
Treatment: Placebo
n=418 Participants
Eligible participants who were hospitalized during treatment
Treatment: Azithromycin
n=415 Participants
Eligible participants who returned to the ED or were hospitalized within 72 hours following randomization
Return Visit
Bacterial
5 Visits
Standard Deviation 1.89
3 Visits
Standard Deviation 1.17
Return Visit
Non-Bacterial
2 Visits
Standard Deviation 1.31
2 Visits
Standard Deviation 1.27

Adverse Events

Treatment - Active (Azithromycin)

Serious events: 7 serious events
Other events: 99 other events
Deaths: 0 deaths

Treatment - Placebo

Serious events: 6 serious events
Other events: 110 other events
Deaths: 0 deaths

Serious adverse events

Serious adverse events
Measure
Treatment - Active (Azithromycin)
n=415 participants at risk
In the azithromycin arm serious adverse events included respiratory distress, bronchospasm, increased work of breathing, respiratory failure, septic shock, and severe cough.
Treatment - Placebo
n=418 participants at risk
In the placebo arm serious adverse events included respiratory distress, respiratory failure, bronchospasm, increased work of breathing, severe cough, and septic shock.
Respiratory, thoracic and mediastinal disorders
Respiratory Distress
0.72%
3/415 • From enrollment until the end of follow-up, up to 21 days
0.48%
2/418 • From enrollment until the end of follow-up, up to 21 days
Respiratory, thoracic and mediastinal disorders
Bronchospasm
0.24%
1/415 • From enrollment until the end of follow-up, up to 21 days
0.00%
0/418 • From enrollment until the end of follow-up, up to 21 days
Respiratory, thoracic and mediastinal disorders
Increased Work of Breathing
0.00%
0/415 • From enrollment until the end of follow-up, up to 21 days
0.48%
2/418 • From enrollment until the end of follow-up, up to 21 days
Respiratory, thoracic and mediastinal disorders
RSV Infection
0.00%
0/415 • From enrollment until the end of follow-up, up to 21 days
0.24%
1/418 • From enrollment until the end of follow-up, up to 21 days
Respiratory, thoracic and mediastinal disorders
Acute Respiratory Failure
0.24%
1/415 • From enrollment until the end of follow-up, up to 21 days
0.00%
0/418 • From enrollment until the end of follow-up, up to 21 days
Infections and infestations
Septic Shock
0.24%
1/415 • From enrollment until the end of follow-up, up to 21 days
0.00%
0/418 • From enrollment until the end of follow-up, up to 21 days
Respiratory, thoracic and mediastinal disorders
Hypercapnic Respiratory Failure
0.24%
1/415 • From enrollment until the end of follow-up, up to 21 days
0.00%
0/418 • From enrollment until the end of follow-up, up to 21 days
Respiratory, thoracic and mediastinal disorders
Cough Increased
0.00%
0/415 • From enrollment until the end of follow-up, up to 21 days
0.24%
1/418 • From enrollment until the end of follow-up, up to 21 days

Other adverse events

Other adverse events
Measure
Treatment - Active (Azithromycin)
n=415 participants at risk
In the azithromycin arm serious adverse events included respiratory distress, bronchospasm, increased work of breathing, respiratory failure, septic shock, and severe cough.
Treatment - Placebo
n=418 participants at risk
In the placebo arm serious adverse events included respiratory distress, respiratory failure, bronchospasm, increased work of breathing, severe cough, and septic shock.
Immune system disorders
S pneumonia Resistant at Baseline
28.9%
13/45 • From enrollment until the end of follow-up, up to 21 days
41.0%
16/39 • From enrollment until the end of follow-up, up to 21 days
Immune system disorders
S pneumonia Resistant at Followup
21.9%
7/32 • From enrollment until the end of follow-up, up to 21 days
8.7%
2/23 • From enrollment until the end of follow-up, up to 21 days
Immune system disorders
Safety Outcome: Bacterial Resistant at baseline (subsample n=209)
23.9%
99/415 • From enrollment until the end of follow-up, up to 21 days
26.3%
110/418 • From enrollment until the end of follow-up, up to 21 days
Immune system disorders
Bacterial Resistant at Baseline
16.2%
16/99 • From enrollment until the end of follow-up, up to 21 days
17.3%
19/110 • From enrollment until the end of follow-up, up to 21 days
Immune system disorders
Bacterial Resistant at Followup
21.7%
18/83 • From enrollment until the end of follow-up, up to 21 days
22.0%
20/91 • From enrollment until the end of follow-up, up to 21 days
Immune system disorders
H Influenzae Resistant at Baseline
0.00%
0/28 • From enrollment until the end of follow-up, up to 21 days
4.8%
1/21 • From enrollment until the end of follow-up, up to 21 days
Immune system disorders
H Influenzae Resistant at Followup
7.1%
2/28 • From enrollment until the end of follow-up, up to 21 days
0.00%
0/20 • From enrollment until the end of follow-up, up to 21 days
Immune system disorders
M catarrhalis Resistant at Baseline
5.4%
4/74 • From enrollment until the end of follow-up, up to 21 days
3.5%
3/86 • From enrollment until the end of follow-up, up to 21 days
Immune system disorders
M catarrahlis Resistant at Followup
1.4%
1/70 • From enrollment until the end of follow-up, up to 21 days
2.4%
2/83 • From enrollment until the end of follow-up, up to 21 days

Additional Information

Fernando D. Martinez, MD

Arizona Board of Regents, University of Arizona

Phone: 5206266387

Results disclosure agreements

  • Principal investigator is a sponsor employee
  • Publication restrictions are in place