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Trial registered on ANZCTR


Registration number
ACTRN12606000509561
Ethics application status
Approved
Date submitted
23/03/2006
Date registered
7/12/2006
Date last updated
30/03/2016
Type of registration
Retrospectively registered

Titles & IDs
Public title
Antibiotics for acute bronchitis
Scientific title
Treatment of acute bronchitis in general practice: A double blind RCT to determine the effectiveness of 500 mg amoxycillin versus placebo in reducing the duration of cough and severity of symptoms
Secondary ID [1] 288880 0
Nil known
Universal Trial Number (UTN)
Trial acronym
ABFAB
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Acute bronchitis 1487 0
Condition category
Condition code
Respiratory 1582 1582 0 0
Other respiratory disorders / diseases

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
500 mg amoxycillin capsules. Oral dose taken three times a day for 6 days.
Intervention code [1] 945 0
Treatment: Drugs
Comparator / control treatment
Placebo (lactose containing) capsules. Oral dose taken three times a day for 6 days.
Control group
Placebo

Outcomes
Primary outcome [1] 2186 0
To determine if amoxycillin, compared to placebo, improves morbidity in adult patients with 'complicated' acute bronchitis in general practice
Timepoint [1] 2186 0
Comparisons at Baseline, Day 7, Day 14 and Day 28
Secondary outcome [1] 3814 0
Medication compliance
Timepoint [1] 3814 0
Day 1 - 6
Secondary outcome [2] 3815 0
Side effects
Timepoint [2] 3815 0
Day 1 - 28

Eligibility
Key inclusion criteria
1) presenting with an acute cough of less than 14 days, 2) at least one other symptom of a respiratory tract infection (sputum production, dyspnoea, wheeze, chest discomfort/pain), 3) at least one 'complicated' acute bronchitis sign (pulse rate >100, respiratory rate >25, oral temperature >38ºC, abnormal chest signs, age >55, confined to bed/very unwell, co-morbidity), 4) have read the patient information sheet and provided written consent, 5) able and willing to follow study requirements.
Minimum age
18 Years
Maximum age
Not stated
Gender
Both males and females
Can healthy volunteers participate?
No
Key exclusion criteria
1) a concurrent chronic respiratory illness that requires ongoing treatment, 2) antibiotics in the previous 3 weeks, 3) immunocompromised, 4) allergic to amoxycillin, penicillin, cephalospirins or beta-lactams, 5) lactose intolerant, 6) community acquired pneumonia, 7) bordatella pertussis.

Study design
Purpose of the study
Treatment
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Capsules containing either amoxycillin or placebo prepared by a hospital pharmacist. Capsules packed in identical vials with a code number according to the randomisation list.
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Computer-generated list of random numbers in permuted blocks with variable block sizes provided by an independent statistician.
Masking / blinding
Blinded (masking used)
Who is / are masked / blinded?
The people receiving the treatment/s
The people administering the treatment/s
The people assessing the outcomes
Intervention assignment
Parallel
Other design features
The patients nor the examining physicians or co-ordinating and data analysis trial staff know which treatment has been allocated until database close.
Phase
Type of endpoint(s)
Efficacy
Statistical methods / analysis
Descriptive statistics will be used to determine the comparability of the treatment groups for baseline patient demographic or characteristics. Count data (such as duration of cough, number of days coughing up phlegm and number of days with a sore throat etc) will be analysed using Poisson Generalised Estimating Equations (GEE) to allow for clustering of patients within doctors. Binary outcomes (such as seen GP for past cough and antibiotics for previous cough etc.) will be analysed using binomial Generalized Estimating Equations (GEE). Normally distributed data (such as frequency of cough and how well they felt today etc from visual analogue scales (VAS)) will be analysed using mixed model analysis of variance. Adjustments for confounders for patient age, gender, co-morbidities and chest signs at study entry and possible patient characteristic imbalances will be made. All analyses will be on an intention to treat basis and the significance level set at 0.05.

Subgroup analysis will be performed on the following:
- Chest signs (vs all)
- All patients >55 yrs (vs all)
- Current smokers (vs all)
- CRP greater than 30 mg/L (vs all)

Adjustments will be made in the analyses to account for contributing confounders of patient age, gender, co-morbidities and chest signs at study entry and possible patient characteristic imbalances.

Recruitment
Recruitment status
Completed
Date of first participant enrolment
Anticipated
Actual
Date of last participant enrolment
Anticipated
Actual
Date of last data collection
Anticipated
Actual
Sample size
Target
Accrual to date
Final
Recruitment in Australia
Recruitment state(s)
SA

Funding & Sponsors
Funding source category [1] 1728 0
Government body
Name [1] 1728 0
National Health and Medical Research Council of Australia - Project Grant 299032
Address [1] 1728 0
GPO Box 1421
Canberra ACT 2601
Country [1] 1728 0
Australia
Primary sponsor type
University
Name
University of Adelaide
Address
North Terrace
Adelaide SA 5005
Country
Australia
Secondary sponsor category [1] 1523 0
None
Name [1] 1523 0
Address [1] 1523 0
Country [1] 1523 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 3192 0
University of Adelaide Human Research Ethics Committee
Ethics committee address [1] 3192 0
Ethics committee country [1] 3192 0
Australia
Date submitted for ethics approval [1] 3192 0
Approval date [1] 3192 0
29/06/2005
Ethics approval number [1] 3192 0
H-74-2003
Ethics committee name [2] 3193 0
Children, Youth and Women's Health Service Research Ethics Committee
Ethics committee address [2] 3193 0
Ethics committee country [2] 3193 0
Australia
Date submitted for ethics approval [2] 3193 0
Approval date [2] 3193 0
07/11/2005
Ethics approval number [2] 3193 0
REC1737
Ethics committee name [3] 3194 0
RACGP National Research and Evaluation Ethics Committee
Ethics committee address [3] 3194 0
Ethics committee country [3] 3194 0
Australia
Date submitted for ethics approval [3] 3194 0
Approval date [3] 3194 0
30/06/2005
Ethics approval number [3] 3194 0
NREEC 05/02

Summary
Brief summary
Acute bronchitis is the 5th most frequent reason to visit a general practitioner (GP), often leading to an antibiotic prescription even though guidelines advise that the infective organism is usually viral. Patient factors are partially responsible for these prescriptions but research indicates that GPs are inconsistent in their labelling of acute bronchitis and may feel the need to use antibiotics “just in case”. Studies indicate that, overall, patients with acute bronchitis may experience only a marginal benefit from antibiotic treatment, and this benefit may be offset by potential side effects.

A recent Cochrane systematic review suggests that some patients may benefit from antibiotics. Based on clinical symptoms, signs and investigations, we think there may be two groups of patients with acute bronchitis - ‘uncomplicated’ and ‘complicated’- the former not requiring antibiotics and the latter, associated with poorer outcomes, who might benefit from their use. By identifying those sub-groups, GPs could be more certain about who to treat (and therefore who not to treat) leading to more rational and cost effective prescribing without compromising patient care.

This is a double blind study which means that the patients have been randomly assigned to recieve either amoxycillin or placebo capsules for 6 days, and neither the patients nor the physicians or trial staff know which treatment has been allocated until database close.
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 35757 0
Prof Nigel Stocks
Address 35757 0
Discipline of General Practice
University of Adelaide
North Terrace
Adelaide SA 5005
Country 35757 0
Australia
Phone 35757 0
+61 8 8313 3462
Fax 35757 0
+61 8 8313 3511
Email 35757 0
nigel.stocks@adelaide.edu.au
Contact person for public queries
Name 10134 0
Prof Nigel Stocks
Address 10134 0
Discipline of General Practice
University of Adelaide
North Terrace
Adelaide SA 5005
Country 10134 0
Australia
Phone 10134 0
+61 8 8313 3462
Fax 10134 0
+61 8 8313 3511
Email 10134 0
nigel.stocks@adelaide.edu.au
Contact person for scientific queries
Name 1062 0
Prof Nigel Stocks
Address 1062 0
Discipline of General Practice
University of Adelaide
North Terrace
Adelaide SA 5005
Country 1062 0
Australia
Phone 1062 0
+61 8 8313 3462
Fax 1062 0
+61 8 8313 3511
Email 1062 0
nigel.stocks@adelaide.edu.au

No data has been provided for results reporting
Summary results
Have study results been published in a peer-reviewed journal?
Other publications
Have study results been made publicly available in another format?
Results – basic reporting
Results – plain English summary