Patients with active AS were randomly assigned to receive infliximab every 6 weeks (Q6), or only upon symptoms recurrence (on-demand), following a loading regimen of infusions at weeks 0, 2, and 6. Patients in the latter group were randomly assigned to receive MTX or not, starting 4 weeks prior to infliximab. Monitoring was performed over one year. The primary end point was the proportion of patients with a 20% improvement response according to the ASsessment in Ankylosing Spondylitis (ASAS) criteria, at week 54.