MADRID – A panel of clinicians with expertise in the management of patients with spondyloarthritis took another step toward better defining this disease category and the goals of its treatment by producing the first "treat-to-target" recommendations for spondyloarthritis.
The new recommendations will "guide physicians, patients, and other stakeholders on how to optimize reduction of signs and symptoms and, ideally, outcomes, and will drive" the current research agenda, Dr. Josef S. Smolen said while presenting the panel’s recommendations at the annual European Congress of Rheumatology.
"Treat to target proposes a stepwise approach to achieving optimal outcomes based on available evidence and expert opinion. Treat to target has been successfully applied to management of diabetes, hypertension, hyperlipidemia, and rheumatoid arthritis," and the new task force set out to address whether it could be used when treating patients with spondyloarthritis (SpA), a question that required the expert task force to review the evidence for setting specific treatment goals for patients with SpA, said Dr. Smolen, professor of medicine at the Medical University of Vienna.
The task force eventually decided that the treat-to-target concept was applicable to SpA, but that the data available so far prevented the task force from setting specific treatment goals. While the recommendations underscore the importance of treating SpA patients with a goal of remission or inactive disease, and failing that, at least low disease activity, they fall short of giving clinicians guidance on how to best measure and define remission or low disease activity or how to achieve these goals.
For example, for axial SpA – the subtype that received the most specific recommendations – the panel advised clinicians to guide treatment decisions by using a "validated composite measure of disease activity" such as the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) plus acute phase reactants, or the Ankylosing Spondylitis Disease Activity Score (ASDAS) with or without functional measures such as the Bath Ankylosing Spondylitis Functional Index (BASFI). But the recommendations say nothing about what scores by these measures would define remission or low disease activity. The recommendations also talk about using other factors to further gauge axial SpA disease activity such as MRI analysis of inflammation and radiographic progression, but again Dr. Smolen provided no specific targets when using these measures.
For other, less well studied types of SpA, the new recommendations were even more nebulous. For psoriatic arthritis, the panel indicated that "validated measures of musculoskeletal disease activity" should be "performed and documented regularly" as should other factors such as spinal and extraarticular manifestations, imaging findings, and comorbidities, but the recommendations gave no specifics on what any of these measures might be or what level might equal remission or low disease. The same held true for peripheral SpA.
Other factors touched on by the new recommendations include the need for individualized and shared decision making between physicians and patients, the need for coordination of care among rheumatologists and other medical specialists who treat SpA patients (dermatologists, gastroenterologists, and ophthalmologists), and the need to take into account extraarticular manifestations of SpA diseases, comorbidities, and treatment risks along with the goal of low disease activity.
"I think it was important to document that there is a paucity of trials that have looked at strategies to treat" SpA. "For rheumatoid arthritis we have strategies, but not in spondyloarthritis, and I think it is important to say that," said Dr. Jürgen Braun, medical director of Rheumazentrum Ruhrgebiet in Herne, Germany.
SpA also lags behind rheumatoid arthritis by not having any treatments proven to slow radiographic progression. "Although we say that it is presumably important to treat inflammation [in patients with SpA], we are not sure," said Dr. Braun, who served as a member of the treat-to-target task force.
Even though the task force’s report highlights the absence of evidence for most facets of SpA management, "in the absence of evidence you need eminence, and that’s what was produced." Dr. Braun predicted that rheumatologists and other clinicians who care for patients with SpA would welcome these new recommendations despite their shortcomings. "What we say is what clinicians feel: If a patient’s CRP is elevated we must do something about it, but the evidence supporting this is limited. Presumably, it is important to treat inflammation, but we are not yet sure," he said in an interview.
"We don’t have trial results yet where you set up a quantifiable endpoint as your target, but that is coming," said Dr. Philip J. Mease, director of the rheumatology clinical research division at Swedish Medical Center in Seattle and a member of the task force. For example, the results from the Tight Control of Psoriatic Arthritis (TICOPA) trial "will tell us whether more aggressive treatment to a quantifiable target is appropriate and makes a difference. We anticipate that it will, but evidence is currently lacking." The primary endpoint of the TICOPA trial is change in the ACR20 response, but the trial includes several other clinical measures as secondary endpoints, including the Assessment in Ankylosing Spondylitis (ASAS), the BASDAI, and the psoriasis area severity index (PASI).