Effect of apremilast on entheseal bone damage in psoriasis patients at risk of developing psoriatic arthritis - data from the prospective, interventional EPOS study

Abstract

BACKGROUND/PURPOSE: A subset of psoriasis (PsO) patients exhibits subclinical entheseal inflammation and bone remodeling placing them at higher risk of developing psoriatic arthritis (PsA). Whether early pharmacological interventions during this phase can modulate these inflammatory and structural changes remains largely unclear. METHODS: In this single-arm, open-label trial (EPos, EUDRACT 2018-000335-27) PsO patients with moderate-to-severe psoriasis, arthralgia, subclinical inflammatory and/or structural bone changes assessed by hand MRI and/or HR-pQCT were included. Patients who had current or past signs of PsA or prior b/tsDMARD exposure were excluded. Participants received apremilast 30 mg BID over 24 weeks. The primary endpoint was the change in structural entheseal lesions (SEL) (number, density and structure) at hand joints assessed by HR-pQCT (week 24). Secondary endpoints were change in bone and inflammatory alterations assessed by MRI (PsAMRIS) as well as clinical response.Safety was monitored RESULTS: Twenty patients (50.0±11.6 years;9 women) were included, all with long-standing PsO and frequent nail and scalp involvement. Over 24 weeks no significant progression in the SEL number was detected while entheseal cortical density and cortical thickness also remained stable. No progression in number and volume of erosions was observed. Total PsAMRIS as marker of inflammation remained stable. Significant improvements in skin disease activity (PASI: 10.9±6.7 vs. 5.2±6.6,p=0.013) and tender joint count (3.2±3.4 vs. 0.8±1.8,p=0.006) was seen. No new safety signals emerged. CONCLUSION: In PsO patients at increased risk of PsA, no significant change in subclinical entheseal bone or inflammatory imaging was observed over 24 weeks of apremilast treatment, while skin disease activity and pain outcomes improved. These findings support further investigation of disease-interception strategies in early psoriatic disease.