Association of the PDE3A-SLCO1C1 locus with the response to anti-TNF agents in psoriasis

Psoriasis is a prevalent autoimmune disease of the skin that causes significant psychological and physical disability. Tumor necrosis factor (TNF)-blocking agents have proven to be highly efficacious in the management of moderate-to-severe psoriasis. However, a significant percentage of patients do not respond to this treatment. Recently, variation at the PDE3A-SLCO1C1 (phosphodiesterase 3A-SoLute Carrier Organic anion transporter family member 1C1) locus has been robustly associated with anti-TNF response in rheumatoid arthritis. Using a cohort of 130 psoriasis patients treated with anti-TNF therapy, we sought to analyze the association of this locus with treatment response in psoriasis. We found a highly significant association between PDE3A-SLCO1C1 and the clinical response to TNF blockers (P=0.0031). Importantly, the allele that was previously associated with the lack of response to rheumatoid arthritis (G allele, single-nucleotide polymorphism rs3794271) was associated with a higher anti-TNF efficacy in psoriasis. The results of this study are an important step in the characterization of the pharmacogenetic profile associated with anti-TNF response in psoriasis.