Secukinumab (Cosentyx®), a first-in-class fully human monoclonal antibody against interleukin-17A, is approved in several countries, including the USA and those of the EU, for the treatment of ankylosing spondylitis (AS). Subcutaneous secukinumab significantly improved the clinical signs and symptoms of AS versus placebo in three of four phase III trials. The benefits of secukinumab were generally seen regardless of whether patients had or had not received previous tumour necrosis factor (TNF) inhibitor therapy, and were sustained during longer-term (up to 5 years) treatment. Secukinumab was also associated with improvements in spinal mobility, physical function, health-related quality of life and work productivity in some of the trials. In MEASURE 1, secukinumab reduced inflammation in the sacroiliac joint, and slowed radiographic progression. Secukinumab was generally well tolerated during up to 5 years’ treatment; the most commonly reported adverse event was nasopharyngitis. In the minority of patients who developed anti-drug antibodies (ADAs), ADAs did not decrease efficacy or increase adverse events. In conclusion, secukinumab is an effective therapy for TNF inhibitor-naive patients with active AS, and provides a useful treatment option for patients who have an inadequate response to or are intolerant of TNF inhibitors.