Condition category
Musculoskeletal Diseases
Date applied
Date assigned
Last edited
Retrospectively registered
Overall trial status
Recruitment status
No longer recruiting

Plain English Summary

Background and study aims
Osteoarthritis (OA) is the most common type of arthritis, affecting millions of people worldwide. It occurs when the protective cartilage on the end of bones wears away. The bones then rub against one another, which can cause stiffness, pain and a reduction in a person’s range of movement. The knee is the most common joint to be affected by OA, and in severe cases, surgery may be the only treatment that can provide patients with relief. A knee arthroplasty, also known as knee replacement surgery, is recommended if the pain from OA is so severe that it is causing disability. In this operation, the diseased cartilage and bone is removed from the surface of the knee joint and replaced with a man-made surface of metal or plastic. This can happen on one side (partial) or both sides (total) of the knee joint, depending on how severe the damage is. Pycnogenol is the trade name of a dietary supplement made from French maritime pine bark extract. Previous studies have shown that it can help to relieve pain and joint stiffness in knee OA patients. Currently little is known about how it does this and whether components of the drug spread through the joints. The aim of this study is to find out how Pycnogenol works in patients with OA and how its components are spread throughout the body.

Who can participate?
Adults with severe knee osteoarthritis who are having knee replacement surgery.

What does the study involve?
Participants are randomly allocated to one of two groups. Those in the first group receive 200mg of Pycnogenol twice a day for three weeks before they are due to have their knee replacement surgery. Those in the second group do not receive any additional treatment in the three weeks leading up to their surgery. Blood samples are collected from all patients at the start of the study, 1-2 days before their surgery and just before/during their surgery, and joint fluid is taken on the day of the surgery. The blood and joint fluid are tested for markers that play a role inflammation and cartilage destruction of the joints.

What are the possible benefits and risks of participating?
There are no direct benefits or risks of participating in the study.

Where is the study run from?
Orthopedic Center for Musculoskeletal Research (Germany)

When is the study starting and how long is it expected to run for?
October 2012 to September 2014

Who is funding the study?
Horphag Research LTD (Cyprus)

Who is the main contact?
1. Professor Petra Högger (Scientific)
2. Dr Lothar Seefried (Public)

Trial website

Contact information



Primary contact

Prof Petra Högger


Contact details

Institut für Pharmazie und Lebensmittelchemie
Am Hubland C7
+49 (0)931 318 5468



Additional contact

Dr Lothar Seefried


Contact details

Orthopedic Center for Musculoskeletal Research
Department of Orthopedics
Brettreichstraße 11
+49 (0)931 8030

Additional identifiers

EudraCT number number

Protocol/serial number


Study information

Scientific title

1. It is possible to detect constituents and/or metabolites of Pycnogenol in serum, blood cells and synovial fluid of patients after ingestion of the extract
2. Constituents and/or metabolites of Pycnogenol influence inflammatory and cartilage metabolism markers in osteoarthritis patients


Study hypothesis

After ingestion of Pycnogenol, components and/or metabolites of the extract are distributed into serum, blood cells and synovial fluid. Bioactive compounds in serum and synovial fluid exhibit molecular effects on key catabolic and inflammatory markers.

Ethics approval

Local Ethics Committee of the Medical Faculty of the University Würzburg, 21/12/2011, ref: 248/11

Study design

Single-centre randomised controlled trial

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 to request a patient information sheet




Patients were randomized into two groups using a computer-generated randomization list which was not accessible to the physicians and nurses who were involved in the patient care and management. Half of the study participants (n= 15) were assigned to the treatment group receiving 200 mg of the French maritime pine bark extract Pycnogenol® per day (twice daily two capsules with each 50 mg) over three weeks prior to the planned surgery. The control group comprised of 15 patients who received no Pycnogenol®.

Blood samples from each study participant were collected before oral intake of Pycnogenol® (V1, basal value); during the intake, approximately 1-2 days before the surgery (V2); and during or shortly before knee surgery (V3), about 12 h after the last dose of Pycnogenol®. On the day of the surgery residual knee cartilage and synovial fluid were also collected. There was no further follow-up.

Intervention type



Drug names

Primary outcome measure

Detection and quantification of constituents and/or metabolites of Pycnogenol in serum, blood cells (before and after intake of Pycnogenol; V1, V2, V3) and synovial fluid (at the time of knee surgery, V3) of patients.

Secondary outcome measures

Measurement of markers of inflammation and cartilage metabolism in the patient's serum, blood cells (before and after intake of Pycnogenol; V1, V2, V3) and synovial fluid (at the time of knee surgery, V3) of patients, e.g. MMP-3, MMP-13, IL-1β, ADAMTS-5.

Overall trial start date


Overall trial end date


Reason abandoned (if study stopped)


Participant inclusion criteria

1. Aged 18 years or over
2. Severe knee osteoarthritis according to the Western Ontario and McMaster Universities Arthritis Index (WOMAC) score
3. Scheduled for an elective arthroplasty (Kellgren-Lawrence grade III-IV)

Participant type


Age group




Target number of participants


Participant exclusion criteria

1. Taking Non-steroidal anti-inflammatory drugs (NSAIDs) or glucocorticoids within the past four weeks
2. Currently received a therapy with anti-coagulants
3. Tested positive for HIV, HCV or HCB
4. Have had a previous or current infection of the affected knee joint

Recruitment start date


Recruitment end date



Countries of recruitment


Trial participating centre

Orthopedic Center for Musculoskeletal Research
Department of Orthopedics Brettreichstraße 11

Trial participating centre

Institute of Pharmacy and Food Chemistry (Institut für Pharmazie und Lebensmittelchemie)
Am Hubland C7

Sponsor information


Horphag Research LTD

Sponsor details

Karaiskaki 38
Kanika Alexander Court
1st floor
Flat/Office 113CD
P.C. 3032

Sponsor type




Funder type


Funder name

Horphag Research LTD

Alternative name(s)

Funding Body Type

Funding Body Subtype


Results and Publications

Publication and dissemination plan

Two publications are planned, one reporting the results of the analysis of componetns and metabolites in serum, blood cells and synovial fluid (pharmacokinetic aspect), the other covering the results of the relative gene expression of cartilage homeostasis markers as well as inflammatory and cartilage metabolism mediators in serum and synovial fluid samples (cellular pharmacodynamic aspect).

Intention to publish date


Participant level data


Basic results (scientific)

Publication list

2017 results in:

Publication citations

Additional files

Editorial Notes

15/02/2018: Publication reference added.