Amgen and Wyeth Pharmaceuticals, a division of Wyeth, announced that the U.S. Food and Drug Administration (FDA) approved an expanded indication for Enbrel (etanercept) as a treatment to improve physical function in patients with moderately to severely active rheumatoid arthritis (RA). Rheumatoid arthritis is a chronic and progressively disabling disease that affects more than two million Americans. Patients can become disabled from irreversible joint damage caused by the disease, limiting their ability to function.
The ability of Enbrel to improve physical function and disability was assessed in three placebo-controlled trials in patients (n=955) with late-stage or early RA. In open-label Enbrel studies, improvements in physical function and disability measures have been maintained for up to four years. The primary tool used to assess improvement was the Health Assessment Questionnaire (HAQ), in which a score of zero indicates no disability.
"Moderate to severe active RA can have devastating effects on patients' lives, limiting their ability to perform even the simplest daily activities like buttoning a shirt or holding a cup of coffee," said Kevin Young, Vice President and General Manager of Amgen's Inflammation Business Unit. "This approval demonstrates the ability of Enbrel to help patients resume normal daily activities, which can be the patients' ultimate goal of therapy."
"Over the past several years, overall improvement in daily activities, including physical function and disability, have become important outcome measures of treatment success for RA patients," said Dr. Victoria Kusiak, Vice President of Global Medical Affairs and North American Medical Director of Wyeth Pharmaceuticals. "By evaluating improvement in physical ability, we gain a deeper understanding of the impact Enbrel can have on the lives of patients with RA."
Patients with early RA treated with Enbrel monotherapy achieved a mean improvement of 0.7 units in their HAQ scores after six months. A change of 0.22 units is considered clinically important. At one year 29% of patients achieved a zero HAQ score.
Many patients with late-stage RA treated with Enbrel (those who had failed at least one disease modifying antirheumatic drug or DMARD), alone or in combination with methotrexate, had significant improvement in their HAQ disability scores, compared with patients who received placebo or methotrexate alone. Improvement occurred within the first month of treatment and was sustained throughout the studies. Across the clinical studies, at six months, mean improvements in the HAQ were approximately 0.6 units in the Enbrel groups vs. 0 and 0.2 units in the placebo groups. At six months 15% of patients on Enbrel alone and 15% of patients on Enbrel plus methotrexate achieved a zero HAQ score vs 0% and 3% on placebo respectively.