Etanercept cohort studie.

1. Patients with the diagnosis rheumatoid arthritis according to the American Rheumatism Association (ARA) 1987 criteria and in ACR 1991 functional classes I, II, and III;

2. The patient is naïve for anti-TNF-alpha therapy or has failed other prior TNF-alpha blockers;

3. DAS 28  3.2;

4. Failure on two previously used DMARDs;

5. Age > 18 and =< 85 years old;

6. Use concurrent methotrexate treatment (5 - 30 mg/week; stable since at least 28 days before initiation) during the study. Subjects may be taking nonsteroidal anti-inflammatory drugs, provided the dose and frequency have been stable for at least 28 days. Subjects may be receiving prednisone therapy < 10 mg/day provided that the dosage has been stable for at least 28 days prior to entry.

1. Pregnancy;

2. Breastfeeding;

3. A history of or current acute inflammatory joint disease of different origin e.g. mixed connective tissue disease, seronegative spondylarthropathy, psoriatic arthritis, Reiter’s syndrome, systemic lupus erythematosus or any arthritis with onset prior to age 16 years;

4. Acute major trauma;

5. Therapy within the previous 60 days with:

A. Any experimental drug;

B. Alkylating agents, e.g. cyclophosphamide, chlorambucil;

C. Antimetabolites;

D. Monoclonal antibodies (including infliximab and etanercept);

E. Growth factors;

F. Other cytokines.

6. Therapy within the previous 28 days with:

A. Parenteral or intraarticular corticoid injections;

B. Oral corticosteroid therapy exceeding a prednisone equivalent of 10 mg daily;

C. Present use of DMARDs other than methotrexate.

7. Receipt of any live (attenuated) vaccines within 4 weeks prior to baseline;

8. Fever (orally measured > 38 °C), chronic infections or infections requiring anti-microbial therapy;

9. Other active medical conditions such as inflammatory bowel disease, bleeding diathesis, or severe unstable diabetes mellitus;

10. Manifest cardiac failure (stage III or IV according to NYHA classification);

11. Progressive fatal disease/terminal illness;

12. A history of lymphoproliferative disease or treatment with total lymphoid irradiation;

13. A white cell count less than 3.5 x 109/l;

14. Platelet count less than 100 x 109/l;

15. Haemoglobin of less than 5.3 mmol/l;

16. Body weight of less than 45 kg;

17. History of drug or alcohol abuse;

18. Any concomitant medical condition which would in the investigator’s opinion compromise the patient’s ability to tolerate, absorb, metabolize or excrete the study medication;

19. Inability to give informed consent;

20. Mental condition rendering the patient unable to understand the nature, scope and possible consequences of the study and/or evidence of an uncooperative attitude.