Combination leflunomide and methotrexate (MTX) therapy for patients with active rheumatoid arthritis failing MTX monotherapy: open-label extension of a randomized, double-blind, placebo controlled trial.

OBJECTIVE: To obtain additional safety and efficacy data on leflunomide (LEF) treatment in combination with methotrexate (MTX) therapy in an open-label extension study in patients with rheumatoid arthritis (RA). METHODS: Following a 24 week, randomized, double-blind trial of adding placebo (PLA) or LEF to stable MTX therapy, patients could enter a 24 week extension. Subjects randomized to LEF and MTX continued treatment [(LEF/LEF) + MTX]. Subjects randomized to PLA and MTX switched to LEF (10 mg/day, no loading dose) and MTX [(PLA/LEF) + MTX]. The double-blind regarding initial randomization was maintained. RESULTS: For subjects in the extension phase, American College of Rheumatology 20% (ACR20) responder rates for the (LEF/LEF) + MTX group were maintained from Week 24 (57/96, 59.4%) to Week 48 (53/96, 55.2%). ACR20 responder rates improved in patients switched to LEF from PLA at Week 24 [(PLA/LEF) + MTX] from 25.0% (24/96) at Week 24 to 57.3% (55/96) at Week 48. Patients in the extension who switched from PLA to LEF without a loading dose exhibited a lower incidence of elevated transaminases compared to patients initially randomized to LEF. Diarrhea and nausea were less frequent during the open-label extension in patients who did not receive a LEF loading dose. CONCLUSION: Response to therapy was maintained to 48 weeks of treatment in patients who continued to receive LEF and MTX during the extension. Importantly, ACR20 response rates after 24 weeks of LEF therapy were similar between patients switched from PLA to LEF without loading dose, and those who received a loading does of LEF (100 mg/day x 2 days) at randomization. Fewer adverse events were reported in patients switched to LEF without a loading dose.

Concomitant leflunomide therapy in patients with active rheumatoid arthritis despite stable doses of methotrexate. A randomized, double-blind, placebo-controlled trial.

BACKGROUND: Disease-modifying antirheumatic drugs may confer greater benefits when combined with the antimetabolite methotrexate. OBJECTIVE: To evaluate the efficacy and safety of leflunomide versus placebo when added to ongoing, stable-dose methotrexate therapy in patients with persistently active rheumatoid arthritis. DESIGN: 24-week, multicenter, randomized, double-blind, placebo-controlled trial. SETTING: 20 centers in the United States and Canada. PATIENTS: Patients with persistent rheumatoid arthritis, as defined by American College of Rheumatology (ACR) criteria, despite receiving methotrexate for at least 6 months. INTERVENTION: Leflunomide or matching placebo added to existing methotrexate therapy. MEASUREMENTS: The primary efficacy variable was the rate of achievement of 20% improvement in ACR criteria (ACR20) at the end of the study. The Health Assessment Questionnaire Disability Index was assessed at each visit, and the Medical Outcomes Study 36-Item Short Form was completed as an end point analysis. RESULTS: In the leflunomide and placebo groups, 46.2% and 19.5% of patients, respectively, met ACR20 criteria at 24 weeks (P < 0.001). Clinical improvement was demonstrated by statistically significant mean changes in individual components of the ACR20 response criteria. Discontinuation rates were similar in both treatment groups (23.1% in the leflunomide group and 24.8% in the placebo group), as were the overall incidences of adverse events (89.2% vs. 89.5%, respectively). Adverse events were predominantly mild or moderate. CONCLUSIONS: Combination therapy with leflunomide and methotrexate provides statistically significant clinical benefit in patients with active rheumatoid arthritis who are receiving methotrexate therapy. Leflunomide plus methotrexate is generally well tolerated and can be used safely with appropriate liver enzyme and hematologic monitoring.

Hydroxychloroquine concentration-response relationships in patients with rheumatoid arthritis.

OBJECTIVE: A dose-response relationship for hydroxychloroquine (HCQ), in terms of the proportion of patients achieving the Paulus 20% criteria for improvement, had previously been observed in patients with rheumatoid arthritis (RA) receiving a 6-week loading regimen of 400, 800, or 1,200 mg HCQ daily. This present retrospective analysis was performed to investigate possible relationships between the blood HCQ and HCQ-metabolite concentrations and measures of efficacy and toxicity. In addition, we sought to ascertain whether further investigation of HCQ/HCQ-metabolite levels might lead to testing of one of these substances as a new antirheumatic drug. METHODS: Patients with active RA (n = 212) began a 6-week, double-blind trial comparing 3 different doses of HCQ at 400, 800, or 1,200 mg/day, followed by 18 weeks of open-label HCQ treatment at 400 mg/day. Patients were repeatedly evaluated for treatment efficacy and toxicity. Blood samples were available from 123 patients for analysis of HCQ, desethylhydroxychloroquine (DHCQ), desethylchloroquine (DCQ), and bisdesethylchloroquine (BDCQ) levels using high-performance liquid chromatography. Achievement of the modified Paulus 20% improvement criteria for response in RA was used as the primary efficacy parameter. Spontaneously reported adverse events were categorized and analyzed as toxicity outcome variables. The relationship between response (efficacy and toxicity) and drug levels was evaluated using logistic regression analysis. RESULTS: The subset of patients with blood concentration data was equivalent to the larger study population in all demographic and outcome characteristics. The mean HCQ, DHCQ, and DCQ elimination half-lives were 123, 161, and 180 hours, respectively. There was a positive correlation between the Paulus 20% improvement criteria response and blood DHCQ concentrations during weeks 1-6 (P < 0.001). A potential relationship between ocular adverse events and BDCQ levels was found (P = 0.036). Logistic regression analysis of adverse events data showed that adverse gastrointestinal events were associated with higher HCQ levels (P = 0.001-0.021) during weeks 1, 2, and 3. CONCLUSION: There is a weak, but predictable, relationship between blood DHCQ concentrations and efficacy of treatment with HCQ. In addition, there is an association between gastrointestinal adverse events and elevated blood HCQ concentrations. Further investigation of these relationships is warranted to see if DHCQ may be introduced as a new antirheumatic drug.