Variability in individual responses of 532 patients with rheumatoid arthritis to first-line and second-line drugs.

Variability in individual responses to drugs used to treat rheumatoid arthritis was studied in 532 patients under care in seven U.S. rheumatology private practices. Among 15 nonsteroidal anti-inflammatory drugs (NSAIDs), estimated continuation of 1,775 courses was 48% at 12 months and 20% at 60 months. Acetylated salicylates, other than plain aspirin, were continued significantly longer than other NSAIDs. Among second-line drugs, estimated continuation of 50% of courses was 10 months for oral gold, 20 months for hydroxychloroquine, 21 months for penicillamine, 25 months for parenteral gold, 27 months for azathioprine, and more than 60 months for methotrexate and prednisone, the only drugs continued by more than 50% of patients 60 months after initiation.