MADRID – Treating patients with axial spondyloarthritis (axSpA) until a specific target is reached is an emerging concept that has gained a lot of traction in the past few years, Pedro Machado, MD, said at the European Congress of Rheumatology.
“The availability of biologic therapies has improved the clinical outcomes for our patients with axial spondyloarthritis and targeting clinical remission or inactive disease is now an achievable treatment goal in clinical practice,” he observed. “This has trigged the question: Is there a role for ‘treat-to-target’ in axial spondyloarthritis?”
Dr. Machado, an honorary consultant in rheumatology and muscle diseases at University College Hospital and the National Hospital for Neurology and Neurosurgery in London, took a critical look at the treat-to-target approach during a clinical science session at the meeting, organized by the European League Against Rheumatism (EULAR).
The concept of treat-to-target is not new, he acknowledged, having been imported from other chronic conditions where there is a very specific target to achieve – such as lowering glycated hemoglobin in diabetes or hypertension or hyperlipidemia in cardiovascular disease.
“The concept involves changing or escalating therapy according to a predefined target under the assumption that this may lead to a better outcome compared to what we call ‘routine care,’ ” Dr. Machado explained.
Treat-to-target is not only well established in nonrheumatic diseases but also has proved to work in patients with rheumatoid arthritis and psoriatic arthritis with evidence from the TICORA (Tight Control of Rheumatoid Arthritis) and TICOPA (Tight Control in Psoriatic Arthritis) trials.
Whether the approach can also work in axSpA is open to debate, and one of the main arguments against using a treat-to-target in axSpA asks, what exactly is the target? While there is no firm agreement yet, Dr. Machado observed that achieving either clinical remission or inactive disease would be the most likely target.
It could be argued this is already being done to some degree, but “we need to be more ambitious,” Dr. Machado said. Indeed, current Assessment of Spondyloarthritis International Society/EULAR recommendations for the treatment of axSpA (Ann Rheum Dis. 2017;76[6]:978–91) note when patients with high disease activity despite sufficient standard treatment should be escalated to treatment with a biologic disease-modifying antirheumatic drug (bDMARD). High disease activity was defined as an Ankylosing Spondylitis Disease Activity Score (ASDAS) of 2.1 or more or a Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) score of 4 or more.
Another argument against using the approach concerns the evidence base. There are no prospective, randomized trials supporting the use of treat-to-target over routine care. However, there is a lot of observational evidence, Dr. Machado said in an interview. Such studies have shown that achieving inactive disease may improve structural outcomes and stop the development of radiographic damage of the spine. Importantly, these observational studies also show that achieving inactive disease may also help to improve patients’ functional outcomes and quality of life.
Evidence backing a treat-to-target approach in axSpA from a randomized, controlled trial may currently be lacking, but the TiCOSPA (Tight Control in Spondyloarthritis) trial is in progress and should help change that, Dr. Machado said.
“The missing bit is a randomized trial, but I would say that the observational evidence is almost enough to advocate a treat-to-target strategy in axial spondyloarthritis.” This was also the view of an international task force that recently published recommendations and overarching principles for a treat-target strategy in spondyloarthritis, including axSpA (Ann Rheum Dis. 2018;77:3-17).
Of course, a treat-to-target approach may not be without its pitfalls. There are a limited number of drugs currently that could be used to “hit the target” of disease activity, Dr. Machado said in his presentation. The approach might also lead to ‘overtreatment,’ and more treatment is not always better as it could not only lead to more adverse events, but it also may mean the approach is not cost-effective.
Depending on the TiCOSPA study results, which are expected next year, Dr. Machado said that “the feasibility and cost-effectiveness of such a strategy in clinical practice also needs to be tested.”