Preventive effects of Echinacea extract on cold and flu symptoms

ISRCTN ISRCTN46631134
DOI https://doi.org/10.1186/ISRCTN46631134
Secondary identifying numbers Protocol Ep/2
Submission date
16/11/2018
Registration date
22/11/2018
Last edited
22/04/2021
Recruitment status
No longer recruiting
Overall study status
Completed
Condition category
Respiratory
Prospectively registered
Protocol
Statistical analysis plan
Results
Individual participant data
Record updated in last year

Plain English summary of protocol

Background and study aims
Colds and flu are very common causes of illness that are usually fairly minor and most often result from infections of the throat and chest. There is not much medical evidence for effective ways of preventing or combating colds and flu. The herbal remedy Echinacea contains substances that have effects in “test-tube” scientific experiments that suggest it may strengthen immune responses in human beings. Although medical research evidence is limited, Echinacea has become a popular treatment with annual sales in the $100s of millions.
This study aims to find out if giving generally healthy adults Echinacea herb powder benefits them by reducing the numbers of colds and flu illnesses they suffer from and the total numbers of days on which they feel ill from these illnesses.

Who can participate?
Generally healthy adults

What does the study involve?
Participants will be randomly allocated to the intervention or control group. Individuals in the intervention group will be given Echinacea to take daily for 8 weeks, whereas individuals in the control group will be given a placebo to take daily for 8 weeks.

What are the possible benefits and risks of participating?
By recording a range of lifestyle factors, participants will recognise and thereby may seek to behave in a way that avoids adverse potential risk factors, and embrace healthy behaviors that reduce susceptibility to colds and flu.
Side effects have not been reported from consuming Echinacea, although as a precaution those who have allergies to plants related to Echinacea such as sunflower seeds, are prone to food allergies, suffering any autoimmune disorders or are pregnant or breast-feeding are advised not to take part in the study.

Where is the study run from?
School of Health Sciences, University of Wolverhampton (UK)

When is the study starting and how long is it expected to run for?
September 2001 to May 2002

Who is funding the study?
Faculty of Science and Engineering, University of Wolverhampton (UK)

Who is the main contact?
Dr David Maslin
david.maslin@yahoo.co.uk

Contact information

Dr david maslin
Scientific

73 Newbridge Crescent
Wolverhampton
wv6 0lh
United Kingdom

Study information

Study designInterventional prospective single-centre double-blinded parallel-group randomised placebo-controlled trial
Primary study designInterventional
Secondary study designRandomised controlled trial
Study setting(s)Community
Study typePrevention
Participant information sheet Not available in digital format, please use the contact details to request a patient information sheet.
Scientific titlePreventive effects of oral Echinacea purpurea dried herb extract against upper respiratory tract infections: a randomised double-blinded placebo-controlled trial
Study objectivesThe extract of the herb Echinacea purpurea prevents symptoms of upper respiratory tract illness. Preventive effects are greatest amongst those with the worst recent history of upper respiratory tract illness.
Ethics approval(s)University of Wolverhampton, School of Health Sciences Ethics Committee, 23/11/2001, no reference number
Health condition(s) or problem(s) studiedUpper respiratory tract infections (URTIs)
InterventionUpper respiratory tract infection (URTI) scores will be taken during an 8 week pre-treatment period. After this, these secores are used to divide the subjects into lower and higher strata. From each of these strata (blocks of 4 individuals), 2 subjects will be randomised to receive Echinacea and 2 will be randomly allocated to receive the placebo using randomised number sequences generated by a statistician.
Participants allocated to receive Echinacea will take Echinacea orally daily, in the form of 88 mg dried pressed Echinacea purpurea juice as a powder together with powdered excipients and inert carrier materials amounting to a total of 500 mg in 1 cellulose capsule.
Participants allocated to the placebo group will receive 1 placebo cellulose capsule to take orally daily, containing physiological inactive filler materials of the same size, shape and colour as the trial dose.
Intervention typeSupplement
Primary outcome measureUpper respiratory tract infection incidence and severity, assessed at the baseline and weekly for the 8 week trial period using the severity scale of Grimm and Muller
Secondary outcome measures1. The following baseline personal data, assessed by study investigators on a study-designed form following recruitment and prior to week 1 of the intervention dose period:
1.1. Gender
1.2. Age
1.3. BMI
2. The following lifestyle information, assessed using a self-report questionnaire at approximately week 4 of the intervention dose period:
2.1. Accomodation
2.2. Transport
2.3. Dietary supplements
2.4. Stress
2.5. Alcohol intake
2.6. Smoking
2.7. Exercise
3. Diet, assessed using a self-report diet diary form at week 4 of the intervention dose period
4. Subjective perceptions of benefit, side-effects and dose identification, assessed by questionnaire at week 8 of the intervention dose period
Overall study start date04/09/2001
Completion date31/05/2002

Eligibility

Participant type(s)Healthy volunteer
Age groupAdult
Lower age limit18 Years
Upper age limit65 Years
SexBoth
Target number of participants120
Key inclusion criteria1. Aged 18-65
2. Generally healthy
Key exclusion criteria1. Gastrointestinal ailments at the time of the study
2. Previous anaphylactic shock
3. Proneness to food allergies (specifically including sunflower seeds)
4. Severe eczema
5. Autoimmune disorders such as lupus or rheumatoid arthritis
6. Pregnant or breastfeeding
Date of first enrolment01/10/2001
Date of final enrolment30/11/2001

Locations

Countries of recruitment

  • England
  • United Kingdom

Study participating centre

University of Wolverhampton
School of Health Sciences
Wolverhampton
wv1 1ly
United Kingdom

Sponsor information

University of Wolverhampton
University/education

Wulfruna Street
Wolverhampton
wv11ly
England
United Kingdom

Phone 01902 321000
Email FSE@wlv.ac.uk
Website https://www.wlv.ac.uk
ROR logo "ROR" https://ror.org/01k2y1055

Funders

Funder type

University/education

University of Wolverhampton
Private sector organisation / Universities (academic only)
Location
United Kingdom

Results and Publications

Intention to publish date01/11/2022
Individual participant data (IPD) Intention to shareYes
IPD sharing plan summaryOther
Publication and dissemination planCurrent publication and dissemination plan as of 22/04/2021:
We aim to publish the results of this trial in "Complementary Therapies in Clinical Practice". The trial results will be sent to experts in the field of Echinacea research (Dr Bruce Barrett, Professor Rudolf Bauer)
IPD sharing planThe datasets generated and/or analysed during the current study during this study will be included in the subsequent results publication.


Previous publication and dissemination plan:
We aim to publish the results of this trial in "Complementary Therapies in Clinical Practice"
Planned submission is by 2019. The trial results will be sent to experts in the field of Echinacea research (Dr Bruce Barrett, Professor Rudolf Bauer)

IPD sharing statement:
The datasets generated during and/or analysed during the current study are/will be available upon request from Dr David Maslin (david.maslin@wlv.ac.uk). Anonymised raw data will be provided in an Excel spreadsheet including baseline personal data (gender, age, BMI), data on basic life styles and outcomes data. This will be available from 30/01/2020 for analyses replicating those in the planned publication. Participants gave consent prior to participation in the trial

Editorial Notes

22/04/2021: The following changes have been made:
1. The intention to publish date has been changed from 01/11/2019 to 01/11/2022.
2. Participant level data has been updated from "Not provided at the time of registration" to "Other".
23/11/2018: Internal review.