Table 1

ASAS consensus for anti-TNF therapy

Specification (definition of the terms)
VAS, visual analogue scale; all VAS can be replaced by a numerical rating scale (NRS).
*The expert is a doctor, usually a rheumatologist, with expertise in inflammatory back pain and the use of biological agents. Experts should be locally defined; †an expert opinion comprises clinical features (history and examination), serum acute phase reactant levels, or imaging results, such as radiographs demonstrating rapid progression or MRI scans indicating inflammation; ‡sulfasalazine: treatment for ⩾4 months at standard target dose of 3 g/day, or maximally tolerated dose unless contraindicated or not tolerated. Treatment for <4 months, where treatment was withdrawn because of intolerance or toxicity or contraindicated.
Patient selection
  • Diagnosis

  • Patients normally fulfilling modified New York Criteria for definitive AS

  • Modified New York criteria 1984 (van der Linden et al9)

    • Radiological criterion

    • Sacroiliitis, grade ⩾II bilaterally or grade III to IV unilaterally

    • Clinical criteria (2 out of the following 3)

    • Low back pain and stiffness for >3 months that improves with exercise but is not relieved by rest

    • Limitation of motion of the lumbar spine in both 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 that anti-TNF treatment should be started†

  • Treatment failure

  • All patients must have had adequate therapeutic trials of at least 2 NSAIDs. An adequate therapeutic trial is defined as:

    • Treatment for ⩾3 months at maximal recommended or tolerated anti-inflammatory dose unless contraindicated

    • Treatment for <3 months where treatment was withdrawn because of intolerance, toxicity, or contraindications

  • Patients with symptomatic peripheral arthritis (normally having a lack of response to a local steroid injection for those with oligoarticular involvement) must have had adequate therapeutic trial of both NSAIDs and sulfasalazine‡

  • Patients with symptomatic enthesitis must have had an adequate therapeutic trial of at least two local steroid injections unless contraindicated

  • Contraindication

  • Women who are pregnant or breastfeeding; 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 prosthesis remains in situ

    • Persistent or recurrent chest infections

    • Indwelling urinary catheter

  • History of lupus or multiple sclerosis

  • Malignancy or premalignancy 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 or Dougados functional index)

  • Pain (VAS, past week, spine at night, due to AS and VAS, past week, spine due to AS)

  • Spinal mobility (chest expansion and modified Schober test and occiput to wall distance and lateral lumbar flexion)

  • Patient’s global assessment (VAS, past week)

  • Stiffness (duration of morning stiffness, spine, past week)

  • Peripheral joints and entheses (number of swollen joints (44 joint count), enthesitis score such as developed in Maastricht, Berlin, or San Francisco)

  • Acute phase reactants (ESR or CRP)

  • Fatigue (VAS)


  • VAS overall level of fatigue/tiredness past week

  • VAS overall level of AS neck, back, or hip pain past week

  • VAS overall level of pain/swelling in joints other than neck, back or hips past week

  • 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 minutes)

Assessment of response
  • Responder criteria

BASDAI: 50% relative change or absolute change of 2 (scale 0–10) and expert opinion: Continuation yes/no
  • Time of evaluation

Between 6 and 12 weeks