Fig. 1

Number of patients who were screened, underwent randomization, and completed 52 weeks of the study. The secukinumab groups received intravenous secukinumab at a dose of 10 mg/kg body weight at baseline and weeks 2 and 4, followed by subcutaneous secukinumab at a dose of 300 mg or 150 mg, starting at week 8 and then every 4 weeks. The placebo group received intravenous placebo at baseline and weeks 2 and 4, followed by subcutaneous placebo every 4 weeks starting at week 8 through week 16. Patients initially assigned to receive placebo were re-randomized at week 16 to receive secukinumab 300 mg or 150 mg. Analyses of primary and secondary efficacy endpoints at week 16 included all patients according to the assigned study treatment at baseline. The most frequent reasons for screening failure included meeting the exclusion criteria of history of ongoing, chronic or recurrent infectious disease or evidence of tuberculosis infection (n = 11), not meeting the inclusion criteria of: active ankylosing spondylitis assessed by total Bath Ankylosing Spondylitis Disease Activity Index ≥4 (0–10) at baseline (n = 9) and total back pain as measured by visual analog scale ≥40 mm (0–100 mm) at baseline (n = 6)