Systemic therapy in treating palmoplantar and scalp psoriasis: A systematic review and network meta-analysis

To the Editor: Plaque psoriasis is a common inflammatory skin disease. Psoriasis of the nails, palms, soles, and scalp is less likely to respond to topical treatments.1 Several systemic treatments for these "difficult-to-treat" psoriasis have been proposed, especially small molecule drugs and biologics.2 However, their efficacy and safety have not been compared. To evaluate the comparative efficacy and safety of different systemic therapies for scalp psoriasis (SP) and palmoplantar psoriasis (PP) subtypes, we conducted a systematic review and network meta-analysis (NMA).