Analgesic action of acetaminophen in symptomatic osteoarthritis of the knee: a randomised controlled study

ISRCTN	ISRCTN14751911
DOI	https://doi.org/10.1186/ISRCTN14751911
Protocol serial number	N/A
Sponsor	Merck Sharp and Dohme (MSD) (Switzerland)
Funders	Merck Sharp and Dohme (MSD) (Switzerland) - gave a Medical School Grant in 2001 to perform the study, and provided the drug Vioxx (rofecoxib). The acetaminophen drugs and the other research costs were paid for from the grant., University Hospital Zurich (Switzerland) - provided the infrastructure

Prospectively registered

Protocol

Statistical analysis plan

Results

Individual participant data

Plain English summary of protocol

Not provided at time of registration

Dr Haiko Sprott
Scientific

Department of Rheumatology and Institute of Physical Medicine
University Hospital Zurich
Gloriastrasse 25
Zurich
8091
Switzerland

Phone	+41 (0)44 2558679
Email	haiko.sprott@usz.ch

Primary study design	Interventional
Study design	Randomised controlled trial
Secondary study design	Randomised controlled trial
Scientific title
Study acronym	Knee study
Study objectives	The study was designed to investigate the analgesic effects and mechanisms of acetaminophen (paracetamol) in symptomatic osteoarthritis (OA) of the knee.
Ethics approval(s)	The study was approved by the local ethical committee (Kantonale Ethikkommission, Spezialisierte Unterkommission fur Spezialfa cher) (ref: 343)
Health condition(s) or problem(s) studied	Osteoarthritis of the knee
Intervention	After washout of earlier OA medications, patients were randomly allocated into two groups treated with either acetaminophen up to 4 g per day (n = 10, age 60-77 years) or rofecoxib 25 mg per day (n = 10, age 48-80 years) for 3 months.
Intervention type	Drug
Phase	Not Specified
Drug / device / biological / vaccine name(s)	Acetaminophen (paracetamol), rofecoxib
Primary outcome measure(s)	The functional status of the knee joint was assessed by the Western Ontario McMaster Universities Osteoarthritis (WOMAC) questionnaire in German. Visits and measurements were scheduled upon entry (T0), month 1 (T1) and month 3 (T3).
Key secondary outcome measure(s)	The intensity of joint pain was evaluated by 100-mm visual analogue scale (VAS) at rest. Visits and measurements were scheduled upon entry (T0), month 1 (T1) and month 3 (T3).
Completion date	31/03/2002

Participant type(s)	Patient
Age group	Adult
Sex	All
Target sample size at registration	20
Key inclusion criteria	Patients and healthy subjects: 20 patients fulfilled the American College of Rheumatology criteria for knee OA accompanied with joint pain (visual analogue scale [VAS] ≥60) were recruited to the study. For control, blood from 20 age and gender-matched healthy subjects was obtained from a local blood bank, the Blutspenderdienst Zürich. All patients signed the informed consent.
Key exclusion criteria	1. Secondary OA as a consequence of inflammation, gout, pseudogout or tumour 2. Kidney insufficiency 3. OA-influencing concomitant diseases 4. Drug medication with opioids
Date of first enrolment	01/11/2001
Date of final enrolment	31/03/2002

Department of Rheumatology and Institute of Physical Medicine

Zurich
8091
Switzerland

Individual participant data (IPD) Intention to share	No
IPD sharing plan summary	Not provided at time of registration
IPD sharing plan

Output type	Details	Date created	Date added	Peer reviewed?	Patient-facing?
Results article	Results	01/06/2006		Yes	No