Combination of methotrexate and sulphasalazine in patients with rheumatoid arthritis: pharmacokinetic analysis and relationship to clinical response

1The influence of sulphasalazine (SASP) on the pharmacokinetics of low dose methotrexate (MTX) and the relation between pharmacokinetic variables and clinical response was studied in 15 patients with active rheumatoid arthritis despite >6 months of SASP treatment