Recent studies have shown that biological drugs approved for treating psoriasis and psoriatic arthritis are not effective in all patients, and that variations in the genome have been associated with different clinical responses or side effects. HLA‐Cw6 gene is associated with more severe and early‐onset psoriasis. Recent reports have shown that HLA‐Cw6 status predicts efficacy of some biologic treatments in psoriasis patients. The Phase 3b SUPREME study (NCT02394561) demonstrated the efficacy of secukinumab in patients with moderate‐to‐severe plaque‐type psoriasis, irrespective of HLA‐Cw6 status at week 24.