Serum interleukin-23 protects, whereas methotrexate treatment stimulates selected components of the metabolic syndrome in patients with SAPHO syndrome

Risankizumab Efficacy in Synovitis, Acne, Pustulosis, Hyperostosis, and Osteitis (SAPHO) Remission: A Case Report on Rheumatologic and Dermatologic Disease Manifestations with Literature Review

SAPHO syndrome is a complex disease that encompasses both inflammatory arthritis and/or osteitis and dermatologic manifestations. It is considered a rare disease, in fact, no clinical trials have been conducted on its therapy and management. Therefore, therapeutic approach is based on small case studies. Here, we described the case of a 63-year-old woman affected by SAPHO syndrome, treated with the selective IL-23p19 antagonist, Risankizumab, after unsuccessful therapies with Methotrexate, Infliximab, Adalimumab, and an allergic reaction to Secukinumab. At the beginning of therapy, in November 2022, the patient presented with arthritis in both knees associated with palmar pustulosis and guttate psoriasis on the trunk. DAPSA score was 24, PtGA 80 mm, PASI score 11.1, and BSA 40%. Thereafter, Risankizumab was started at the standard dosage of 150 mg. At week 24 patient achieved clinical remission, DAPSA score was 8, PtGA was 30 mm, PASI was 1, and BSA 2.5. Patient maintained clinical remission state at the subsequent week 52 evaluation. At the same time, the patient did not report any adverse effects. Health-related quality of life was also assessed at the same time points aforementioned, showing significant improvement. In conclusion, this case report wants to point out the efficacy and safety of Risankizumab in SAPHO syndrome, reporting a sustained disease remission through a 12 months long follow-up period. We can consider IL-23p19 targeted therapy as a novel treatment option for SAPHO-with a high efficacy potential-especially on patients that have already been treated with other biologics.

Treatment and monitoring of SAPHO syndrome: a systematic review

BACKGROUND AND OBJECTIVES

Synovitis acne pustulosis hyperostosis osteitis (SAPHO) is a rare heterogeneous disease of unknown aetiopathology. Externally validated and internationally agreed diagnostic criteria or outcomes and, as a result, prospective randomised controlled trials in SAPHO are absent. Consequently, there is no agreed treatment standard. This study aimed to systematically collate and discuss treatment options in SAPHO.

METHODS

Following 'Preferred Reporting Items for Systematic Reviews and Meta-Analyses' guidance, a systematic literature search was conducted using PubMed, Scopus and Web of Science databases. Prospective clinical studies and retrospective case collections discussing management and outcomes in SAPHO involving five or more participants were included. Articles not published in English, studies not reporting defined outcomes, and studies solely relying on patient-reported outcomes were excluded.

RESULTS

A total of 28 studies (20 observational, 8 open-label clinical studies) reporting 796 patients of predominantly European ethnicity were included. Reported therapies varied greatly, with many centres using multiple treatments in parallel. Most patients (37.1%) received non-steroidal anti-inflammatory drugs alone or in combination. Bisphosphonates (22.1%), conventional (21.7%) and biological (11.3%) disease-modifying antirheumatic drugs were the next most frequently reported treatments. Reported outcomes varied and delivered mixed results, which complicates comparisons. Bisphosphonates demonstrated the most consistent improvement of osteoarticular symptoms and were associated with transient influenza-like symptoms. Paradoxical skin reactions were reported in patients treated with TNF inhibitors, but no serious adverse events were recorded. Most treatments had limited or mixed effects on cutaneous involvement. A recent study investigating the Janus kinase inhibitor tofacitinib delivered promising results in relation to skin and nail involvement.

CONCLUSIONS

No single currently available treatment option sufficiently addresses all SAPHO-associated symptoms. Variable, sometimes descriptive outcomes and the use of treatment combinations complicate conclusions and treatment recommendations. Randomised clinical trials are necessary to generate reliable evidence.