Abbott, a global, broad-based health care company, presented at the American College of Rheumatology Annual Scientific Meeting (ACR) in Chicago, the  results from long-term open-label extensions of the PREMIER and DE019 phase 3 studies, which evaluated Humira (adalimumab) plus methotrexate (MTX) for up to eight years in patients with early moderate to severe rheumatoid arthritis (RA) and up to 10 years in patients with long-standing moderate to severe RA, respectively.

In both studies, patients were assessed for disease activity, improvement in physical function and inhibition of radiographic progression, including the percentage of patients with no further radiographic progression (change in modified total Sharp score of = 0.5).

"Treating patients with RA requires consideration of managing outcomes beyond the signs and symptoms of the disease; for example, it is critically important to improve and maintain physical function to the greatest extent possible, and to inhibit joint damage, as assessed by radiographic progression," said Arthur Kavanaugh, M.D., Professor of Medicine, University of California San Diego, Division of Rheumatology, Allergy and Immunology. "DE019 and PREMIER provide additional longer term data that support the value of treating both early and long-standing moderate to severe RA with TNF inhibitors such as adalimumab."

DE019 and PREMIER are among the longest open-label extension trials in RA. Humira now has eight years of clinical response, radiographic inhibition and physical function data in early moderate to severe RA and 10 years of data in patients with long-standing RA. The results of these long-term extension studies add to the breadth of evidence that rheumatologists have when managing their patients with a chronic, painful and potentially debilitating disease such as RA.

"The ability to inhibit the progression of the disease and improve physical function is the current benchmark for RA treatment," said John Leonard, M.D., senior vice president, Pharmaceuticals Research and Development, Abbott. "When RA is not treated effectively, the radiographic consequences are irreversible and potentially can be devastating for patients. Humira has accumulated an extensive body of long-term radiographic inhibition data in both early and long-standing RA."

PREMIER was a phase 3, randomized, controlled trial in MTX-naïve patients with early moderate to severe RA. Patients received MTX, Humira or Humira plus MTX for two years of blinded treatment. The controlled portion of the trial demonstrated the radiographic, clinical and functional superiority of initial combination therapy over the individual monotherapies. A total of 299 patients went on to receive open-label Humira (with or without MTX at the investigator's discretion) treatment through year eight. Of these 299 patients, 103 were initially treated with Humira plus MTX, 96 were initially treated with MTX and 100 were initially treated with Humira in the controlled portion of the trial. This posthoc analysis evaluated the eight year completers cohort with radiographic data available at baseline and year eight.

Results were measured using mean change in modified total Sharp score (mTSS), which looks at the patients’ joint erosion score and joint space narrowing; Disease Activity Score 28 joint counts (DAS28), which is a composite index that includes variables such as the number of tender and swollen joints and either erythrocyte sedimentation rate or C-reactive protein (CRP), and may include the patients’ assessment of disease activity.

Following up to eight years of Humira therapy (with or without MTX), the 299 patients overall had a mean change in mTSS of 8.6, a mean DAS28 of 2.6 and a mean Health Assessment Questionnaire Disability Index (HAQ-DI) of 0.6. Approximately half of patients experienced an absence of swollen (52.5 percent) and tender (47.9 per cent) joints. Patients initially randomized to Humira plus MTX in the blinded trial (n=103) demonstrated mean change in mTSS, joint erosion and joint space narrowing at year eight of 3.8, 1.4, 2.4, respectively, and more than 40 per cent of patients had no further radiographic progression (defined as change in mTSS of less than or equal to 0.5). Seventy-one percent of patients in this group had DAS28 <2.6, and 60 percent had HAQ-DI of less than 0.5.

DE019 was a phase 3, randomized, controlled trial in which patients with long-standing RA and an inadequate response to MTX were randomized to one year of Humira 40 mg every other week, Humira 20 mg weekly or placebo injections; all received concomitant MTX. The controlled portion of the trial demonstrated the clinical and radiographic superiority of Humira plus MTX over placebo plus MTX.

A total of 202 patients continued on open-label Humira plus MTX treatment through year 10. Of the 202 patients, 80 patients were initially treated with HUMIRA 40 mg every other week, 66 were initially treated with Humira 20 mg weekly and 56 were initially treated with placebo. Patients initially randomized to Humira 40 mg every other week plus MTX had mean change in mTSS of 0.7, and approximately 50 per cent had no radiographic progression (defined as change in mTSS of less than or equal to 0.5) after 10 years of treatment with Humira.

Humira (adalimumab) is a prescription medicine used alone, with methotrexate, or with certain other medicines to reduce the signs and symptoms of moderate to severe rheumatoid arthritis in adults. It may prevent further damage to bones and joints and may help with the ability to perform daily activities.