BACKGROUND: Secukinumab has shown sustained efficacy and safety in several manifestations of psoriasis. OBJECTIVES: GESTURE investigated the long-term (2·5-year) safety and efficacy of 150 mg and 300 mg subcutaneous secukinumab in 205 patients with moderate-to-severe palmoplantar psoriasis. METHODS: GESTURE was a randomized, double-blind, placebo-controlled, multicentre, phase IIIb trial conducted across 15 countries. The study was 140 weeks long and consisted of four periods: screening (up to 4 weeks), treatment period 1 (16 weeks), treatment period 2 (116 weeks) and post-treatment follow-up (8 weeks). Eligible patients were aged ≥ 18 years with moderate-to-severe palmoplantar psoriasis and at least one plaque outside of the palms and soles. Efficacy was assessed via a palmoplantar Investigator's Global Assessment (ppIGA) and the palmoplantar Psoriasis Area and Severity Index (PASI). RESULTS: The primary end point, a ppIGA score of 0 or 1, was met at week 16. The effect was sustained over 2·5 years with 59% [95% confidence interval (CI) 43·5-74·1] and 53% (95% CI 35·1-69·6) of patients in the secukinumab 300 mg and 150 mg groups, respectively, achieving clear or almost clear palms and soles (ppIGA 0 or 1). At 2·5 years, the mean palmoplantar PASI percentage was reduced in both the secukinumab 300 mg group (-74·7%) and the secukinumab 150 mg group (-61·6%). A total of 17% (secukinumab 300 mg group) and 18% (secukinumab 150 mg group) of patients experienced no difficulty in hands and feet functionality, as indicated by the palmoplantar quality of life instrument overall scores. The safety profile was favourable. CONCLUSIONS: GESTURE revealed that secukinumab provides a strong and sustained response over 2·5 years in challenging-to-treat palmoplantar psoriasis.