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CompletedNCT01129128Updated Jun 21, 2012Results posted

Three Arm Trial of Immune Effects of Echinacea

An interventional study of Echinacea purpurea product and Echinacea purpurea product in Upper Respiratory Tract Infections, sponsored by University of Washington. Completed at 1 site in United States. Open to participants aged 21 Years to 65 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2012-06-21.

Sponsored by University of Washington · Not applicable, Interventional, and Basic science

Phase
Not applicable
Study type
Interventional
Enrollment
67
Allocation
Randomized
Ages
21 Years to 65 Years
Sex
All
01

Study summary

The goal of this study is to determine if either of two, commercially available, Echinacea purpurea products stimulate the immune system. For the study, 60 healthy adults will be randomized to receive one of the two Echinacea purpurea products or placebo for 10 days. Blood will be drawn to assess immune markers just before beginning the study medication, during the 10 day course of medication and after completing the course of medication. It is postulated that adults receiving either of the Echinacea products will have evidence of immune stimulation and those receiving placebo will not.

02

Conditions studied

  • Upper Respiratory Tract Infections

Keywords

  • Echinacea
  • immune modulation
  • prevention
03

In context

Respiratory Tract Infections

1,052 studies on the registry are indexed under Respiratory Tract Infections; 147 are open to participants now.

This study's enrollment of 67 is below the median of 196 across 715 interventional studies indexed under Respiratory Tract Infections.

Browse Respiratory Tract Infections studies →

Lead sponsor

University of Washington is the lead sponsor of 1,431 studies on the registry; 226 are open to participants now.

Of its 158 completed or terminated interventional studies of FDA-regulated products, 136 (86%) have results posted.

Browse University of Washington studies →

Counted across the registry records on this site, refreshed daily.

04

Who can participate

Ages eligible
21 Years to 65 Years
Sexes eligible
All
Accepts healthy volunteers
Yes

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.

Inclusion criteria

  • Healthy adult (based on a screening health questionnaire)
  • Speaks and reads English.
  • If female of child-bearing potential, willing to use contraception to prevent pregnancy during the study.
  • No use of any medication (other than multivitamins, essential fatty acids, oral contraceptives and probiotics) for 2 weeks prior to first dose of study.
  • Willing to abstain from ingesting edible mushrooms for 2 weeks prior and throughout study.
  • Willing to eat less than 2 garlic cloves per day for 2 weeks prior and during the study period

Exclusion criteria

Exclusion Criteria:

  • Pregnancy or currently breastfeeding.
  • History of autoimmune disease or immune disorders.
  • History of asthma.
  • History of allergic rhinitis.
  • History of physician diagnosed eczema, psoriasis or other skin condition that could mask an Echinacea-induced rash.
  • Known allergic reaction to Echinacea or related species, specifically ragweed (Ambrosia), chamomile (Matricaria), goldenrod (Solidago), and sunflower (Helianthus).
  • Known allergic reaction to xylitol sweetener, glycerine, citric acid, or citrus fruits
05

Study design

Phase
Not applicable
Primary purpose
Basic science
Allocation
Randomized
Intervention model
Parallel assignment
Masking
Triple (Participant, Care provider, Investigator)
Enrollment
67 participants (actual)

Study arms

  • Active comparator
    Echinacea preparation 1

    Commercially available Echinacea purpurea product

    Biological: Echinacea purpurea product

  • Active comparator
    Echinacea preparation 2

    Commercially available Echinacea purpurea product

    Biological: Echinacea purpurea product

  • Placebo comparator
    Placebo

    Inert liquid that is similar in appearance and taste to the active Echinacea products

    Biological: Placebo

Interventions

06

What researchers measure

Primary outcomes

  1. Peak Level of TNF Alpha

    Highest level of TNF alpha while taking study medication

    Time frame: 1-10 days after starting study medication

Secondary outcomes

  1. Peak Level IL-6

    Highest level of IL-6 while taking study medication

    Time frame: 1-10 days after starting study medication

  2. Peak Level Interferon Gamma

    Highest level of Interferon gamma while taking study medication

    Time frame: 1-10 days after starting study medication

  3. Peak Level IL-2

    Highest level of IL-2 while taking study medication

    Time frame: 1-10 days after starting study medication

  4. Number of Participants With Adverse Events as a Measure of Safety and Tolerability

    Adverse events such as nausea or rash in participants receiving an Echinacea formulation or placebo will be compared

    Time frame: 1- 30 days after starting study medication

07

Results

Posted Jun 5, 2012
Limitations and caveats
Levels of TNF alpha, IL-6, IL-2 and Interferon gamma varied widely limiting chance of detecting differences.

Participant flow

Healthy adult volunteers enrolled from May 2010 through March 2011

Participant flow — Overall Study
MilestoneCommercially Available Echinacea Product #1 (5 ml/Dose)Commercially Available Echinacea Product #2 (1 ml/Dose)Placebo
Started222223
Completed191819
Not completed344
Withdrew: Lost to follow-up221
Withdrew: Protocol violation010
Withdrew: Withdrawal by subject013
Withdrew: Physician decision100

Outcome measures

PrimaryPeak Level of TNF Alpha

Highest level of TNF alpha while taking study medication

Time frame:
1-10 days after starting study medication
Reported as:
Mean · pg/ml
Peak Level of TNF Alpha
pg/mlCommercially Available Echinacea Product #1 (5 ml/Dose)Commercially Available Echinacea Product #2 (1 ml/Dose)Placebo
Peak Level of TNF Alpha436 ± 5101467 ± 2330721 ± 1272
Statistical analysis
  • Commercially Available Echinacea Product #1 (5 ml/Dose) vs Placebo · Regression, Linear · p = 0.87 · Mean difference (final values): -173controlled for baseline levels and performed log transformation of TNF alpha levels to account for skewed distribution of values
  • Commercially Available Echinacea Product #2 (1 ml/Dose) vs Placebo · Regression, Linear · p = 0.82 · Mean difference (final values): 705controlled for baseline levels and performed log transformation of TNF alpha levels to account for skewed distribution of values
SecondaryPeak Level IL-6

Highest level of IL-6 while taking study medication

Time frame:
1-10 days after starting study medication
Reported as:
Mean · pg/ml
Peak Level IL-6
pg/mlCommercially Available Echinacea Product #1 (5 ml/Dose)Commercially Available Echinacea Product #2 (1 ml/Dose)Placebo
Peak Level IL-616296 ± 3744844901 ± 7986828526 ± 61921
Statistical analysis
  • Commercially Available Echinacea Product #1 (5 ml/Dose) vs Placebo · Regression, Linear · p = 0.82 · Mean difference (final values): -15793controlled for baseline levels and performed log transformation of IL-6 levels to account for skewed distribution of values
  • Commercially Available Echinacea Product #2 (1 ml/Dose) vs Placebo · Regression, Linear · p = 0.68 · Mean difference (final values): 23472controlled for baseline levels and performed log transformation of IL-6 levels to account for skewed distribution of values
SecondaryPeak Level Interferon Gamma

Highest level of Interferon gamma while taking study medication

Time frame:
1-10 days after starting study medication
Reported as:
Mean · pg/ml
Peak Level Interferon Gamma
pg/mlCommercially Available Echinacea Product #1 (5 ml/Dose)Commercially Available Echinacea Product #2 (1 ml/Dose)Placebo
Peak Level Interferon Gamma74 ± 122146 ± 321121 ± 292
Statistical analysis
  • Commercially Available Echinacea Product #1 (5 ml/Dose) vs Placebo · Regression, Linear · p = 0.90 · Mean difference (final values): -16controlled for baseline levels and performed log transformation of Interferon gamma levels to account for skewed distribution of values
  • Commercially Available Echinacea Product #2 (1 ml/Dose) vs Placebo · Regression, Linear · p = 0.76 · Mean difference (final values): -12controlled for baseline levels and performed log transformation of Interferon gamma levels to account for skewed distribution of values
SecondaryPeak Level IL-2

Highest level of IL-2 while taking study medication

Time frame:
1-10 days after starting study medication
Reported as:
Mean · pg/ml
Peak Level IL-2
pg/mlCommercially Available Echinacea Product #1 (5 ml/Dose)Commercially Available Echinacea Product #2 (1 ml/Dose)Placebo
Peak Level IL-282 ± 79148 ± 32168 ± 64
Statistical analysis
  • Commercially Available Echinacea Product #1 (5 ml/Dose) vs Placebo · Regression, Linear · p = 0.98 · Mean difference (final values): -0.5controlled for baseline levels
  • Commercially Available Echinacea Product #2 (1 ml/Dose) vs Placebo · Regression, Linear · p = 0.34 · Mean difference (final values): 39controlled for baseline levels
SecondaryNumber of Participants With Adverse Events as a Measure of Safety and Tolerability

Adverse events such as nausea or rash in participants receiving an Echinacea formulation or placebo will be compared

Time frame:
1- 30 days after starting study medication
Reported as:
Number · participants
Number of Participants With Adverse Events as a Measure of Safety and Tolerability
participantsCommercially Available Echinacea Product #1 (5 ml/Dose)Commercially Available Echinacea Product #2 (1 ml/Dose)Placebo
Number of Participants With Adverse Events as a Measure of Safety and Tolerability141816

Adverse events

Collected over day 1 (first dose of study medication) through day 30. Non-serious events are listed at a 5% frequency threshold.

Adverse event summary by group
GroupDeathsSeriousOther
Commercially Available Echinacea Product #1 (5 ml/Dose)—0/22 (0%)14/22 (63.6%)
Commercially Available Echinacea Product #2 (1 ml/Dose)—0/22 (0%)18/22 (81.8%)
Placebo—0/22 (0%)16/22 (72.7%)
Most frequent other events
Showing 10 of 20
Most frequent other events
EventCommercially Available Echinacea Product #1 (5 ml/Dose)Commercially Available Echinacea Product #2 (1 ml/Dose)Placebo
Nasal congestionRespiratory, thoracic and mediastinal disorders5/227/228/22
Gas/indigestionGastrointestinal disorders6/223/222/22
HeadacheNervous system disorders4/225/226/22
Weakness/fatigueGeneral disorders5/224/223/22
Sore throatRespiratory, thoracic and mediastinal disorders2/225/224/22
Abdominal pain/crampsGastrointestinal disorders4/223/221/22
Appetite: increasedGastrointestinal disorders4/220/221/22
NauseaGastrointestinal disorders4/222/222/22
Thirst: increasedMetabolism and nutrition disorders4/221/222/22
Sleep: insomnia, restlessGeneral disorders3/224/223/22

Baseline characteristics

Age, Categorical
Age, Categorical(Participants)Commercially Available Echinacea Product #1 (5 ml/Dose)Commercially Available Echinacea Product #2 (1 ml/Dose)PlaceboTotal
<=18 years0000
Between 18 and 65 years22222367
>=65 years0000
Age Continuous
Age Continuous(years)Commercially Available Echinacea Product #1 (5 ml/Dose)Commercially Available Echinacea Product #2 (1 ml/Dose)PlaceboTotal
Mean34.1 ± 10.635.1 ± 13.528.2 ± 8.032.4 ± 13.1
Sex: Female, Male
Sex: Female, Male(Participants)Commercially Available Echinacea Product #1 (5 ml/Dose)Commercially Available Echinacea Product #2 (1 ml/Dose)PlaceboTotal
Female16141747
Male68620
Region of Enrollment
Region of Enrollment(participants)Commercially Available Echinacea Product #1 (5 ml/Dose)Commercially Available Echinacea Product #2 (1 ml/Dose)PlaceboTotal
United States22222367
08

Study locations

1 site
  • Bastyr University
    Kenmore, Washington 98028, United States
09

Timeline

Tracking since Sep 25, 2026
Not marked actual or estimatedDates not marked actual or estimated

The record gives a start of May 2010, a primary completion of Mar 2011 and a completion of Mar 2011. It does not say whether these dates are actual or estimated.

Results were first posted in Jun 2012, 1 year 3 months after primary completion.

How these figures are worked out, and which studies are left out of them.

Registered
May 14, 2010
First posted
May 24, 2010
Start
May 2010
Primary completionActual
Mar 2011
CompletionActual
Mar 2011
Results first posted
Jun 5, 2012
Last update
Jun 21, 2012
What these dates mean
Start.
When the first participant enrolled; while estimated, when the study expects to open to recruitment.
Primary completion.
When the last participant was examined or treated to collect data for the study's main question, its primary outcome. A study that stopped early gives the date its data collection stopped.
Completion.
When the last participant's last visit took place, for every outcome, secondary ones and side effects included: the end of the study. Often later than primary completion, sometimes the same day.
Actual and Est.
Actual means the registry says the date has happened. Est. (estimated) is a date the sponsor plans or expects. It can still move, and the sponsor is expected to change it to actual once it has passed.
No changes since tracking began. The registry record was last updated on Jun 21, 2012, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
10

Registry details

Key details

Study ID
NCT01129128
Lead sponsor
University of Washington
Collaborators
National Center for Complementary and Integrative Health (NCCIH)
Responsible party
James Taylor (Professor, University of Washington) — Principal investigator
First posted
May 24, 2010
Start date
May 2010
Primary completion
Mar 2011
Completion
Mar 2011
Results posted
Jun 5, 2012
Last update
Jun 21, 2012

Study contacts

James A Taylor, MD
principal investigator · University of Washington

Oversight

Data monitoring committee
No
View the source record on ClinicalTrials.gov ↗

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