Safety and Microvascular Effect of Four-Year Aminaphtone Administration in Systemic Sclerosis Patients.

BACKGROUND

Endothelial and microvascular damage is a hallmark of systemic sclerosis (SSc), an autoimmune connective tissue disease characterized by progressive skin and organ fibrosis. Aminaphtone (3-Methyl-1,4-dioxo-1,4-dihydro-naphthalen-2-yl-amino-benzoate) is a synthetic molecule used to treat microvascular disorders. Nailfold videocapillaroscopy (NVC) is the most reliable non-invasive method for assessing microvascular status and disease progression in SSc patients.

AIM: To evaluate long-term safety and potential beneficial effects of aminaphtone on microcirculation in SSc.

METHODS

Seventy-six SSc patients (68 females, 8 males; mean age 69 ± 15 years) fulfilling the 2013 ACR/EULAR criteria and presenting Raynaud's phenomenon received aminaphtone (75 mg twice daily) in addition to stable standard therapy (ST). Forty age- and sex-matched SSc patients treated with ST alone served as controls. Side effects were monitored every six months. NVC was performed at baseline and after 1 and 4 years, using the Cutolo classification ("Early", "Active", "Late" patterns) to evaluate microvascular damage progression.

RESULTS

Aminaphtone showed a high long-term retention rate (89.5%) over four years. Eight of 76 patients (10.5%) discontinued treatment due to mild transient intolerance or poor compliance; no serious adverse events were reported. NVC patterns remained stable in 91% of treated patients. Compared with controls, aminaphtone-treated patients showed a slower transition from "Active" to "Late" NVC pattern (120 ± 64 vs 50 ± 26 months, p = 0.05). Linear mixed-effects modelling showed a significantly slower capillary density decline in the aminaphtone group over 48 months (p < 0.05) in both "Early" and "Active" scleroderma pattern subgroups. On multivariate linear regression, this effect was independent of age, disease phenotype, and concomitant therapies.

CONCLUSION

Aminaphtone appears safe and well tolerated during long-term treatment in SSc patients with secondary Raynaud's phenomenon. The stability of NVC scleroderma patterns and the independent protective effect on capillary loss suggest a potential adjunctive role of aminaphtone in limiting microvascular damage progression when added to ST in SSc.