Condition category
Musculoskeletal Diseases
Date applied
Date assigned
Last edited
Retrospectively registered
Overall trial status
Recruitment status

Plain English Summary

Not provided at time of registration

Trial website

Contact information



Primary contact

Dr Sarah Brien


Contact details

Complementary Medicine Research Unit
University of Southampton
Aldermoor Health Centre
Aldermoor Close
SO16 5ST
United Kingdom
+44 (0)23 8024 1069

Additional identifiers

EudraCT number number


Protocol/serial number

Version 20

Study information

Scientific title

A randomised, double-blind, placebo-controlled, dose-ranging two-centre study to evaluate the efficacy and safety of Devil's Claw in the treatment of knee and hip osteoarthritis


Study hypothesis

1. Devil's Claw has anti-inflammatory properties (as assessed by the reduction in pain, stiffness and disability aspects on the Western Ontario and McMaster Universities Arthritis Index [WOMAC]) in chronic osteoarthritis (OA) of the knee and/or hip after 16 weeks of treatment, as compared to placebo.
2. A dose response effect exists in the treatment of osteoarthritis of the knee/hip by Devil's Claw.

Ethics approval

Southampton and South West Hampshire, Local Research Ethics Committees, approval: 14/04/2004, ref: LREC 049/04/t

Study design

Randomised double-blind placebo-controlled dose-ranging two-centre study

Primary study design


Secondary study design

Randomised controlled trial

Trial setting


Trial type


Patient information sheet

Not available in web format, please use the contact details below to request a patient information sheet


Osteoarthritis of knee and/or hip


Patients randomised to one of four groups:
1. Placebo medication
2. Devil's Claw (240 mg/d extract, equivalent dose of 2.4 - 4.8 mg/d)
3. Devil's Claw (960 mg/d extract, equivalent dose of 9.6 - 19.2 mg/d)
4. Devil's Claw (1920 mg/d extract, equivalent dose of 19.2 - 40.4 mg/d)

Intervention type



Not Applicable

Drug names

Devil's Claw (Harpagophytum procumbens)

Primary outcome measures

Reduction in WOMAC total score from baseline to week 16.

Secondary outcome measures

1. Secondary efficacy analysis
2. Change in WOMAC subscales (pain, stiffness, disability) from baseline to end of treatment at week 16
3. Quality of Life assessments (Short Form health survey [SF-36])
4. Changes in the subject's well-being
5. Changes in subject's overall global assessment
6. Changes in attitudes and health beliefs to Complementary/Alternative Medicine (CAM)
7. Group differences between adverse event reporting

Overall trial start date


Overall trial end date


Reason abandoned

Lack of funding/sponsorship


Participant inclusion criteria

1. Patients with either a pragmatic diagnosis of:
1.1. Osteoarthritis of the knee, with no other known rheumatological condition and who report the following clinical features (based on the American College of Rheumatology [ACR] classification for knee OA1):
1.1.1. Knee pain on most days of the previous month
1.1.2. Morning stiffness of less than 30 minutes duration
1.1.3. "Stiffness" in resting the joint, and
1.1.4. Aged over 40 years
1.2. Osteoarthritis of the hip, with no other known rheumatological condition and who report the following clinical features (based on the ACR classification for hip OA2) - hip pain on most days of the previous month and at least two of the following three features:
1.2.1. Erythrocyte sedimentation rate (ESR) less than 20 mm/hour
1.2.2. Radiographic femoral or acetabular osteophytes
1.2.3. Radiographic joint space narrowing (superior, axial and/or medial), and
1.2.4. Aged over 45 years of age
The diagnosis of osteoarthritis will be confirmed by X-ray.
2. Only patients who have grade 2 to 4 of the Kellgren and Lawrence scale will be recruited (The Kellgren and Lawrence scale ranges from grade zero to grade four where grades zero and one represent doubtful osteoarthritic changes and therefore a doubtful diagnosis)
3. Patients who have been on stable medication (conventional or complementary, including nutritional medicine) for the past three months, but are still getting symptoms (incomplete responders)
4. Only those patients who record baseline pain scores on the WOMAC scale of at least 20 mm on the Visual Analogue Scale (VAS) for a minimum of six out of seven days monitored during the period from Clinic Visit one (screening) and Clinic Visit two (baseline)
5. Ability to comply with the requirements of the study and to give informed consent
6. For women of child-bearing potential: negative pregnancy test

Participant type


Age group




Target number of participants


Participant exclusion criteria

1. Participation in an investigational trial within 30 days prior to enrolment
2. Previous treatment with Devil's Claw within 90 days prior to enrolment
3. Patients awaiting a replacement knee or hip joint
4. Patients with other conditions that cause pain
5. Patients with congenital dislocation of the hip
6. Patients who have had operations on their hip due to previous trauma
7. Patients with severe co-morbidities - including severe cardiac or pulmonary disease and cancer
8. Dementia, psychoses, or other significant impairment of mental status that would prohibit sufficient comprehension, provision of informed consent and to allow undertaking of the necessary self-care or toxicity reporting
9. Patients taking corticosteroid medication
10. Known allergies against any of the ingredients of the treatments
11. Patients who would be unable to complete the self assessment forms, or to attend for X-ray and clinical examination
12. Patients with other known rheumatic disease such as rheumatoid arthritis
13. Patients with the diagnosis gout
14. Patients who report a red or hot swollen joint (which is unlikely to be due to OA), and would require further rheumatological assessment
15. Patients with conditions known to be contraindicated to the study medication i.e. patients with gastric or duodenal ulcers; gallstones; patients taking drugs for arrhythmias; patients with heart failure
16. Patients who are pregnant, trying to become pregnant or breastfeeding

Recruitment start date


Recruitment end date



Countries of recruitment

United Kingdom

Trial participating centre

University of Southampton
SO16 5ST
United Kingdom

Sponsor information


University of Southampton (UK)

Sponsor details

University Road
SO17 1BJ
United Kingdom
+44 (0)23 8059 8672

Sponsor type




Funder type

Research organisation

Funder name

Southampton Complementary Medicine Research Trust (UK)

Alternative name(s)

Funding Body Type

Funding Body Subtype


Funder name

University of Southampton (UK)

Alternative name(s)

Funding Body Type

private sector organisation

Funding Body Subtype



United Kingdom

Funder name

Pascoe Pharmazeutische Praparate GmbH (Germany)

Alternative name(s)

Funding Body Type

Funding Body Subtype


Results and Publications

Publication and dissemination plan

Not provided at time of registration

Intention to publish date

Participant level data

Not provided at time of registration

Results - basic reporting

Publication summary


Publication citations

Additional files

Editorial Notes

21/03/2016: added link to results - basic reporting. Please note that this trial was stopped on 04/06/2007 due to lack of funding.