Psoriatic arthritis: novel targets add to a therapeutic renaissance

Secukinumab leads to shifts from stage-based towards response-based disease clusters-comparative data from very early and established psoriatic arthritis

BACKGROUND

Limited information exists about the very early forms of psoriatic arthritis. In particular, differences and responsiveness of patient-reported outcomes (PROs) in very early as compared to established PsA have not been investigated to date.

METHODS

Cross-sectional and prospective longitudinal evaluation of PROs related to pain (VAS), physical function (HAQ-DI, SF-36 physical), mental function (SF-36 mental), impact of psoriatic skin (DLQI), joint (PsAID), and global disease (VAS) in two small prospective observational studies on secukinumab 300 mg over 6 months in very early disease patients (IVEPSA study, N = 20) and established PsA (PSARTROS study, N = 20). Cluster analysis was performed at baseline and 24-weeks of follow-up.

RESULTS

While responses in pain and physical activity-related PROs to secukinumab were more pronounced in established PsA than a very early disease, effects on PROs related to general health perception, as well as those related to emotional and mental well-being, were modified in a similar way in very early disease and established PsA. Cluster analysis based on global disease activity and PROs showed that baseline clusters reflected very early disease and established PsA, while after secukinumab treatment these clusters were abolished and new clusters based on differential responses to physically and mentally oriented PROs formed.

CONCLUSIONS

Inhibition of IL-17A by secukinumab leads to comprehensive improvement of general health perception and mental well-being in very early and established PsA, while overall responses in pain and physical activity are more pronounced in established disease. Most importantly, treatment restructures the original patients' clusters based on disease stage and leads to the formation of new clusters that reflect their response in physical and mental-orientated PROs.

TRIAL REGISTRATION

NCT02483234 , registered 26 June 2015, retrospectively registered.

Biological and synthetic target DMARDs in psoriatic arthritis

Psoriatic arthritis (PsA) is a chronic multi-faceted immune-mediated systemic disorder, characterized by articular, cutaneous, enthesis, nail and spine involvement. Articular manifestations of PsA are particularly common and highly disabling for patients, while the heterogeneous clinical subsets of the disease are challenging for clinicians. In recent years, research has made many advances in understanding the pathogenesis of the disease from genetic, epigenetic and molecular points of view. New drugs are now available for the treatment of this condition, and, in particular, TNF-alfa inhibitors, historically the first biologicals approved in PsA, are now juxtaposed by new biological disease modifying anti-rheumatic drugs (bDMARDs) with different modes of action. Targeting IL-12/IL-23 p40 common subunit with ustekinumab, IL-17A with secukinumab and ixekizumab, T cells co-stimulation with abatacept, is now possible, safe and effective. Moreover, targeted synthetic molecules with oral administration are available, with the possibility to interfere with phosphodiesterase-4 and JAK/STAT pathways. Indeed, new drugs are under development, with the possibility to target selectively IL-17 receptor, IL-23, and other key molecular targets in the pathogenesis of this condition. In this narrative review, we provide an up-to-date overview of the current application of biological and targeted synthetic DMARDs in the field of PsA, with particular regard to the clinical significance of this possibility to target a higher number of distinct immune-pathways.

Disease interception with interleukin-17 inhibition in high-risk psoriasis patients with subclinical joint inflammation-data from the prospective IVEPSA study

BACKGROUND

A specific subset of psoriasis patients is characterized by subclinical inflammatory changes. These patients frequently present with arthralgia and have a higher risk to develop psoriatic arthritis (PsA). We hypothesized that IL-17A inhibition in this subset of patients can intercept the link between skin and joint disease and resolves pain and inflammatory changes.

METHODS

Psoriasis, but no PsA, patients were included in the open prospective exploratory Interception in very early PsA (IVEPSA) study. Patients had to have nail or scalp involvement or a high psoriasis area severity index (PASI) (> 6) as well as inflammatory or erosive changes in MRI or CT. Patients received treatment with the anti-interleukin (IL)-17A antibody secukinumab over 24 weeks. Clinical assessments of skin and joint disease were done at baseline and after 12 and 24 weeks, MRI and CT at baseline and after 24 weeks.

RESULTS

Twenty patients were included, 85% of them reporting arthralgia and 40% had tender joints at the examination. Eighty-three percent had at least one inflammatory lesion in the MRI, most of them synovitis/enthesitis. Skin disease (PASI: p < 0.002; BSA: p < 0.003) and arthralgia (VAS pain: p < 0.003) significantly improved after 24 weeks. Total PsAMRIS (p = 0.005) and synovitis subscore (p = 0.008) also significantly improved. Erosions and enthesiophytes did not progress, while bone mass in the distal radius significantly (p = 0.020) increased after 24 weeks.

CONCLUSIONS

These data suggest that very early disease interception in PsA is possible leading to a comprehensive decline in skin symptoms, pain, and subclinical inflammation. IVEPSA therefore provides rationale for future early interventions with the concept to prevent the onset of PsA in high-risk individuals.

TRIAL REGISTRATION

Trial registry name PSARTROS; trial registry number: NCT02483234; June 26, 2015.