BACKGROUND: Anti-tumor necrosis factor (TNF)-α therapies represent a significant innovation in therapy for psoriasis. However, a significant number of psoriasis patients do not respond well to TNF blockers or show an insufficient control of disease activity on a long-term basis.OBJECTIVE/AIM: The aim of this study was to recognize specific clinical factors that could be associated with a non-response to any available TNF blockers in patients with moderate-to-severe plaque psoriasis.MATERIALS AND METHODS: The authors reviewed the medical records of all patients who had started etanercept, infliximab, adalimumab and had achieved a minimum of 24 months follow-up. The authors identified subjects who were not responsive to all available anti-TNF agents, whatever the chronology of their use.RESULTS: A total of 110 patients were retrospectively examined. Thirteen patients were identified as "non-responders" to all available TNF-α blockers. Current smoking at the start of anti-TNF therapy was associated with non-response to TNF blockers. The group of "non-responders" presented a high mean body mass index and a high baseline PASI score with respect to the group of responders.CONCLUSIONS: The data showed that the majority of non-responder patients were smokers, overweight or obese and had a high baseline PASI score. Concomitant arthritis was not significantly associated with non-response.