INTRODUCTION
Rosacea is a chronic dermatologic disease that affects approximately 16 million people in the United States.1,2 Its features include centrofacial persistent erythema, flushing, telangiectasia, and/or papules and pustules.3-5Persistent facial erythema is the most common, bothersome, and therapeutically challenging feature of rosacea.3,6-9 Most approved topical pharmacologic agents for rosacea reduce the papules and pustules but are unable to address persistent erythema. They lack the appropriate mechanism to target the underlying fixed changes in superficial cutaneous vasculature, which are regulated by adrenoceptors at the neuromuscular junction that mediate vasoconstriction and vasodilation.7,10-13 Most patients prefer rosacea therapies that show a rapid and noticeable clinical benefit for persistent erythema from the beginning of therapy. An immediate reduction of erythema may affect the likelihood that patients will continue with long-term treatment for this chronic disease.7,8,14,15In 2017, the US Food and Drug Administration (FDA) approved oxymetazoline hydrochloride cream 1.0% (oxymetazoline; Rhofade™, Allergan plc, Dublin, Ireland), the first α1A-adrenoceptor agonist that causes vasoconstriction of the cutaneous microvasculature, for the topical treatment of persistent facial erythema associated with rosacea in adults.10,16,17 Data from two identically designed, phase 3, pivotal, vehicle-controlled trials (REVEAL) demonstrated that oxymetazoline applied topically once daily for 29 days significantly reduced moderate to severe persistent facial erythema of rosacea at 3, 6, 9, and 12 hours postdose on day 29 and was safe and well tolerated over 4 weeks.18,19 The primary efficacy endpoint of these studies was a 2-grade or greater composite improvement from baseline scores on the Clinician Erythema Assessment (CEA) scale with photonumeric guide and Subject Self-Assessment for rosacea facial redness (SSA) scale with photo guide. Although the 2-grade or greater composite clinician- and patient-assessed improvement in rosacea facial redness satisfies FDA criteria for rosacea indication approval, this outcome is not the only clinically
