Disease activity improvements with optimal discriminatory ability between treatment arms: applicability in early and established rheumatoid arthritis clinical trials.

BACKGROUND: The ACR20 has been validated as the best discriminator of efficacy in placebo-controlled trials, but not in head-to-head trials comparing effective therapies in patients with rheumatoid arthritis (RA). We assessed the most discriminatory ACR response and most discriminatory percent improvement in disease activity measures for Simplified Disease Activity index (SDAI), Clinical Disease Activity index (CDAI), and 28-joint Disease Activity Score based on C-reactive protein (DAS28(CRP)) using different patient populations and trial designs. METHODS: Data from two placebo-controlled studies in established RA and two head-to-head studies in early RA were analyzed. The numeric ACR response for each treatment and P value for the difference between treatments were calculated at multiple time points to determine the ACR response associated with the lowest P value. Similarly, values for percent improvement from baseline in SDAI, CDAI, and DAS28(CRP) with the most discrimination between treatments were examined. RESULTS: In the head-to-head early RA trials, the minimum P value and greatest treatment difference between the active comparator arms at 6 months was achieved at higher ACR rates and greater percent improvements in other disease activity measures. In established RA, lower responses (minimum P value and maximum treatment difference) and smaller improvements in disease activity scores had better discriminatory ability at 6 months. CONCLUSIONS: The most discriminatory ACR response rate and percent improvement in disease activity measures were higher in head-to-head active comparator trials in early RA versus placebo-controlled trials in established RA. This difference should be considered in future clinical trial designs. TRIAL REGISTRATION: NCT00195663, NCT00420927, NCT00195702.

Long-term use of adalimumab as monotherapy after attainment of low disease activity with adalimumab plus methotrexate in patients with rheumatoid arthritis.

OBJECTIVE: To evaluate long-term clinical, functional and radiographic outcomes in an open-label extension (OLE) study in patients with rheumatoid arthritis (RA) receiving adalimumab monotherapy or adalimumab+methotrexate following attainment of low disease activity (LDA) with adalimumab+methotrexate. METHODS: Methotrexate-naive patients with early RA were randomised to adalimumab, methotrexate or adalimumab +methotrexate in a double-blind, 2-year study. Patients who completed the study and achieved LDA (28-joint Disease Activity Score using C reactive protein (DAS28(CRP)<3.2) could receive adalimumab monotherapy for up to 8 additional years in the OLE; open-label methotrexate could be added per investigator's discretion. This post hoc analysis included data up to OLE year 3 (study year 5) from patients receiving adalimumab+methotrexate who achieved LDA at year 2 followed by adalimumab monotherapy or methotrexate reinitiation. Normal physical function was defined as Disability Index of the Health Assessment Questionnaire <0.5 and radiographic non-progression as change in modified total Sharp score ≤0.5. RESULTS: Of 140 patients initiating adalimumab monotherapy, 84 (60%) received adalimumab only (methotrexate non-use) and 56 (40%) reinitiated methotrexate (methotrexate use) during OLE treatment. Median (IQR) time to first methotrexate use was 5.1 (0.1-31.4) weeks. Among methotrexate users, 61% retained LDA, 48% achieved DAS28(CRP) <2.6, 45% had normal physical function and 46% had no radiographic progression at year 5; for non-users, 63%, 50%, 58% and 50%, respectively, achieved these milestones. Adverse event rates were similar between methotrexate non-use and use patients. CONCLUSIONS: Adalimumab monotherapy effectively maintained good clinical, functional and radiographic outcomes for up to 3 additional years in ≥50% of patients who attained LDA after 2 years of adalimumab+methotrexate therapy. TRIAL REGISTRATION NUMBER: NCT00195663; Post-results.

Testing treat-to-target outcomes with initial methotrexate monotherapy compared with initial tumour necrosis factor inhibitor (adalimumab) plus methotrexate in early rheumatoid arthritis.

OBJECTIVES: To compare responses in patients with early rheumatoid arthritis (RA) initially treated with the tumour necrosis factor inhibitor (TNFi) adalimumab+methotrexate (MTX) versus MTX monotherapy who may have continued receiving MTX or switched to adalimumab rescue therapy after inadequate response to MTX. METHODS: OPTIMA enrolled MTX-naive patients with active RA for <1 year. This post hoc analysis determined the proportion of patients, stratified by initial treatment, who achieved 28-joint modified Disease Activity Score based on C reactive protein <3.2, normal function and/or no radiographic progression at weeks 26, 52 and 78. RESULTS: Significantly greater proportions of patients initially treated with adalimumab+MTX (n=466) compared with MTX monotherapy (n=460) achieved good clinical (53% vs 30%), functional (45% vs 33%) and radiographic (87% vs 72%) outcomes at week 26. From weeks 26 to 78, adalimumab rescue patients achieved similar clinical and functional outcomes versus patients initially treated with adalimumab+MTX. However, significantly more patients initially treated with adalimumab+MTX had no radiographic progression at weeks 52 and 78 versus patients initially treated with MTX (both timepoints: 86% vs 72%). CONCLUSIONS: In early RA, starting with MTX monotherapy and adding TNFi after 26 weeks yields similar longer term clinical results as starting with TNFi+MTX combination therapy but allows a small but significant accrual of radiographic damage.

Achieving comprehensive disease control in patients with early and established rheumatoid arthritis treated with adalimumab plus methotrexate versus methotrexate alone.

OBJECTIVE: To evaluate the achievement of comprehensive disease control (CDC) following 1 year of treatment with adalimumab+methotrexate versus methotrexate alone and whether early achievement of remission (at week 24 or 26) is associated with CDC at week 52 in patients with either early or established rheumatoid arthritis (RA). METHODS: Post hoc analyses were conducted in three clinical studies assessing treatment with adalimumab+methotrexate: DE019 (NCT00195702) enrolled patients with established RA who were methotrexate inadequate responders; OPTIMA (NCT00420927) and PREMIER (NCT00195663) enrolled methotrexate-naive patients with early RA. In OPTIMA, patients not achieving stable low disease activity at weeks 22 and 26 in the placebo+methotrexate group could receive open-label adalimumab+methotrexate for 52 weeks (Rescue ADA arm). CDC was defined as the simultaneous achievement of clinical remission (DAS28(CRP)<2.6), normal function (HAQ-DI<0.5) and absence of radiographic progression (ΔmTSS≤0.5). RESULTS: Regardless of disease duration, significantly more patients receiving adalimumab+methotrexate achieved CDC compared with methotrexate alone. In the adalimumab+methotrexate group, a numerically greater proportion of patients with early RA (~25%) versus established RA (14%) achieved CDC at 1 year; achievement of CDC was notably greater among patients who met criteria for remission at week 24 or 26 (~50% of patients with early RA and 39% with established RA). CONCLUSION: Treatment with adalimumab+methotrexate increases the likelihood of achieving CDC in patients with either early or established RA. Clinical remission at week 24 or 26 is associated with achievement of CDC at week 52. TRIAL REGISTRATION NUMBER: DE019 (NCT00195702), OPTIMA (NCT00420927), PREMIER (NCT00195663); Post-results.