This secondary proteomic analysis, nested within a 12-week multicenter RCT (PRRERCT), investigated systemic plasma protein changes and predictive biomarkers of paroxetine (25 mg/day oral) response in 24 adult women with refractory erythematous rosacea (CEA score ≥3).
Paroxetine significantly reduced mean CEA scores from 3.1 to 2.3 and Flushing Assessment Tool scores from 3.1 to 2.0 (P<.001). Proteomic analysis identified 497 differentially expressed proteins; candidate biomarkers OLFML3 (AUC 0.87, 95% CI 0.70–1.00) and IGFBP2 (AUC 0.80, 95% CI 0.55–1.00) showed the highest predictive value for clinical response.
- Very small sample (n=24), all female, limiting generalizability to men and broader populations. - Wide confidence intervals for AUC estimates (e.g., IGFBP2 lower bound 0.55) signal substantial statistical uncertainty. - Exploratory/secondary proteomic analysis; findings are hypothesis-generating and require independent replication.
Paroxetine may improve erythema and flushing in refractory rosacea via neuro-vascular-immune pathways, but the sample is too small to change practice. OLFML3 and IGFBP2 are early candidate biomarkers worth tracking in future validation studies.
