| Factor | Criteria |
| Patient selection: | |
| Diagnosis | Patients normally fulfilling modified New York criteria for definitive ankylosing spondylitis |
| Modified New York criteria 19843 | |
| Radiological criterion: sacroiliitis, grade ⩾II bilaterally or grade III to IV unilaterally | |
| Clinical criteria (two of the following three): low back pain and stiffness for more than 3 months which improves with exercise but is not relieved by rest; limitation of motion of the lumbar spine in the sagittal and frontal planes; limitation of chest expansion relative to normal values correlated for age and sex | |
| Active disease | Active disease for ⩾4 weeks |
| BASDAI ⩾4 (0–10) and an expert* opinion† | |
| Treatment failure | All patients should have had adequate therapeutic trials of at least two NSAIDs. An adequate therapeutic trial is defined as: |
| Treatment for at least 3 months at maximum recommended or tolerated anti-inflammatory dose unless contraindicated | |
| Treatment for <3 months where treatment was withdrawn because of intolerance, toxicity, or contraindications | |
| Patients with pure axial manifestations do not have to take DMARDs before anti-TNF treatment can be started | |
| Patients with symptomatic peripheral arthritis should have an insufficient response to at least one local corticosteroid injection if appropriate | |
| Patients with persistent peripheral arthritis must have had a therapeutic trial of sulfasalazine‡ | |
| Patients with symptomatic enthesitis must have failed appropriate local treatment | |
| Contraindications | Women who are pregnant or breast feeding; effective contraception must be practised |
| Active infection | |
| Patients at high risk of infection including: | |
| Chronic leg ulcer | |
| Previous tuberculosis (note: please follow local recommendations for prevention or treatment) | |
| Septic arthritis of a native joint within the past 12 months | |
| Sepsis of a prosthetic joint within the past 12 months, or indefinitely if the joint remains in situ | |
| Persistent or recurrent chest infections | |
| Indwelling urinary catheter | |
| History of lupus or multiple sclerosis | |
| Malignancy or pre-malignancy states excluding: | |
| Basal cell carcinoma | |
| Malignancies diagnosed and treated more than 10 years previously (where the probability of total cure is very high) | |
| Assessment of disease: | |
| ASAS core set for daily practice | Physical function (BASFI) |
| Pain (NRS/VAS, past week, spine at night, from ankylosing spondylitis and NRS/VAS, past week, spine, from ankylosing spondylitis) | |
| Spinal mobility (chest expansion, modified Schober, occiput to wall distance and lateral lumbar flexion) | |
| Patient global assessment (NRS/VAS, past week) | |
| Stiffness (duration of morning stiffness, spine, past week) | |
| Peripheral joints and entheses (number of swollen joints (44 joints count), enthesitis score such as MASES, Berlin, or San Francisco) | |
| Acute phase reactants (ESR or CRP) | |
| Fatigue (NRS/VAS) | |
| BASDAI | NRS/VAS overall level of fatigue/tiredness, past week |
| NRS/VAS overall level of ankylosing spondylitis neck, back or hip pain, past week | |
| NRS/VAS overall level of pain/swelling in joints other than neck, back or hips, past week | |
| NRS/VAS overall discomfort from any areas tender to touch or pressure, past week | |
| VAS overall level of morning stiffness from time of awakening, past week | |
| Duration and intensity (VAS) of morning stiffness from time of awakening (up to 120 min) | |
| Assessment of response: | |
| Responder criteria | BASDAI: 50% relative change or absolute change of 20 mm (on a scale between 0 and 100) and expert opinion in favour of continuation |
| Time of evaluation | Between 6 and 12 weeks |
*The expert is a doctor, usually a rheumatologist, with expertise in ankylosing spondylitis and the use of biological agents (expert should be locally defined); †the expert should consider clinical features (history and examination), serum acute phase reactant levels and/or imaging results, such as radiographs demonstrating rapid progression or MRI indicating ongoing inflammation; ‡sulfasalazine: treatment for at least 4 months at standard target dose or maximally tolerated dose unless contraindicated or not tolerated. Treatment for less than 4 months, where treatment was withdrawn because of intolerance or toxicity or contraindicated.
BASDAI, Bath Ankylosing Spondylitis Disease Activity Index; BASFI, Bath Ankylosing Spondylitis Functional Index; CRP, C-reactive protein; DMARD, disease-modifying antirheumatic drug; ESR, erythrocyte sedimentation rate; MASES, Maastricht Ankylosing Spondylitis Enthesis Score; NSAID, non-steroidal anti-inflammatory drug; VAS, visual analogue scale (all VAS can be replaced by a numerical rating scale (NRS)).