Global healthcare company, Abbott has presented results from the phase III ABILITY-1 study of Humira (adalimumab) in patients with active non-radiographic axial spondyloarthritis (axSpA), a debilitating condition that primarily presents with inflammatory low back pain and can be accompanied by the presence of the HLA-B27 gene, arthritis, and inflammation in the eye and/or gastrointestinal tract.

At week 12, more than twice as many Humira patients compared to those receiving placebo achieved the primary endpoint of 40 per cent improvement in the Assessment of SpondyloArthritis international Society criteria (ASAS 40). These results were presented at the American College of Rheumatology Annual Scientific Meeting (ACR) in Chicago.

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

Spondyloarthritis (SpA) is a group of diseases that share common clinical, radiographic and genetic features. SpA includes ankylosing spondylitis (AS), psoriatic arthritis (PsA), reactive arthritis, enteropathic or Inflammatory Bowel Disease (IBD)-related arthritis and undifferentiated SpA. SpA can be categorized according to which part of the body is mainly affected – axial or peripheral. ASAS has proposed and validated new classification criteria for axial and peripheral SpA that incorporate the use of magnetic resonance imaging (MRI), in addition to traditional X-rays, for visualizing sacroiliitis (inflammation of the sacroiliac joint which connects the lower spine and pelvis). People with non-radiographic axSpA have similar signs and symptoms as those with AS but do not have X-ray evidence of structural damage in the form of sacroiliitis. The ASAS criteria are designed to facilitate classification of people with non-radiographic axSpA who may otherwise remain undiagnosed.

ABILITY-1 is the first large pivotal study to use the ASAS criteria to classify non-radiographic axial SpA patients, as well as evaluate an anti-tumor necrosis factor medication (anti-TNF) in treating patients with non-radiographic axSpA. ABILITY-1 also used the ASAS 40 response criteria for the primary endpoint instead of the less stringent ASAS 20 response criteria.

“There is a tremendous unmet need for effective treatments for patients with non-radiographic axSpA,” said Philip Mease, MD, chief, Swedish Hospital Rheumatology Clinical Research Division, Seattle, Washington. “Adalimumab has been shown to be an effective treatment for two other spondyloarthritides: ankylosing spondylitis and psoriatic arthritis. The results of this study are encouraging for its potential in treating another condition within this group of diseases,” he added.

In the study, a significantly higher percentage of HUMIRA patients achieved the primary endpoint (36.3 per cent vs. 14.9 per cent, P<0.001) and other clinical and imaging outcomes compared to placebo. During the double-blind period, safety analyses for all 192 randomized patients revealed comparable results for HUMIRA and placebo: adverse events (AEs) (57.9 and 58.8 per cent, respectively), serious AEs (3.2 and 1.0 per cent, respectively) and infectious AEs (29.5 and 28.9 per cent, respectively).

“HUMIRA is one of the most comprehensively studied biologics on the market, and Abbott continues to innovate by exploring new treatment arenas,” said John Leonard, MD, senior vice president, Pharmaceuticals Research and Development, Abbott. “Our scientific experience with HUMIRA serves as a strong foundation to fulfill unmet clinical needs, such as non-radiographic axSpA, and expand treatment options available to patients.”

ABILITY-1 is an ongoing multi-country, phase III study designed to evaluate the efficacy and safety of HUMIRA in axSpA patients without radiographic sacroiliitis. Patients were assessed using a number of disease activity measures, including the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI). Eligible patients fulfilled the ASAS axSpA criteria but not modified New York criteria for the diagnosis of AS, had a BASDAI score of =4 cm, a total back pain visual analogue scale (VAS) score of =40 mm and inadequate response/intolerance/contraindication for Non-Steroidal Anti-Inflammatory Drugs (NSAIDs). Patients (n=192) were randomized 1:1 to Humira (40 mg every other week) or placebo for 12 weeks followed by a 92-week open-label extension period where all patients are treated with Humira.

Baseline demographics/disease characteristics were comparable between Humira and placebo groups. The primary endpoint was ASAS 40 response at week 12.

Other efficacy endpoints evaluated included: ASAS 20, ASAS 5/6, ASAS partial remission, BASDAI 50, Ankylosing Spondylitis Disease Activity Score (ASDAS) inactive disease state, mean change in C-reactive protein (CRP), mean change in Spondyloarthritis Research Consortium of Canada (SPARCC) sacroiliac joint and spine scores.

Humira is not approved for the treatment of spondyloarthritides other than ankylosing spondylitis and psoriatic arthritis.

Humira is a TNF blocker that affects the immune system and can lower the ability to fight infections. People treated with Humira are at an increased risk for developing serious infections that may lead to hospitalization or death. Reported serious infections include tuberculosis (TB) and infections caused by viruses, fungi, or bacteria that have spread throughout the body. People should be tested for TB before Humira use and monitored for signs and symptoms of TB during therapy. People at risk of TB may be treated with medicine for TB. Treatment with Humira should not be started in a person with an active infection, unless approved by a doctor. It should be stopped if a person develops a serious infection.