Difficult-to-Treat Axial Spondyloarthritis: A New Challenge.

Axial spondyloarthritis is a common form of chronic inflammatory rheumatic disease in adults, the treatment of which is based on non-pharmacological elements on the one hand, and pharmacological options on the other, such as non-steroidal anti-inflammatory drugs in the first line, followed by biological or targeted synthetic treatments. The therapeutic objective is remission or a low level of disease activity; if this objective is not achieved, the treatment is rotated or changed. Multiple changes is one factor illustrating the inability to achieve disease control and may lead to the notion of a difficult-to-treat disease (D2T). This requires a consensual definition including, beyond the number or therapeutic changes, the assessment of all the dimensions of the disease (objective signs of inflammation, residual pain, degenerative changes, psychosocial context). Recognising D2T patients will enable us to identify a particular population and the factors associated with this condition. When faced with a D2T disease, we need to analyse the causes of treatment failure and take into account the different components of the disease and the patient. In the absence of any prospect of new therapeutic targets in the short term for this disease, patient management may involve intensification of non-pharmacological means and evaluation of new therapeutic strategies such as combinations of targeted treatments.