Pharmaceutical Benefits Scheme criteria for the use of tumour necrosis factor-alpha inhibitors in the treatment of ankylosing spondylitis in Australia: are they evidence based?

BACKGROUND: In 2004, the Pharmaceutical Benefits Scheme (PBS) listed infliximab as a subsidised treatment for ankylosing spondylitis (AS). Eligibility to receive this treatment for AS involved fulfilling several criteria. AIM: To examine the medical literature concerning response to tumor necrosis factor (TNF)-alpha inhibitors in AS and compare with the PBS criteria for these agents.
METHODS: Review of published studies and analysis of the PBS criteria for the prescription of TNF inhibitors for the treatment of AS to assess whether the published criteria are evidence based.
RESULTS: The published findings on the prediction of response to TNF inhibitors in the treatment of AS suggest that age, duration of disease, disease activity, functional status at the time of commencement of TNF inhibitors and, possibly, level of acute phase reactants predict the outcome of treatment with TNF inhibitors in AS. The PBS criteria do not reflect the published findings on predictors of response to TNF inhibitors.
CONCLUSION: The current PBS criteria that need to be fulfilled for patients to receive subsidised treatment with TNF inhibitors for AS are not evidence based and will lead to the selection of patients with established disease while excluding patients with early disease.