Missing doses of tumour necrosis factor drugs leads to poorer response rates
What was already known?
Anti-TNF drugs (e.g. etanercept, certolizumab, adalimumab and golimumab) are biologic drugs that have radically improved treatment options for patients with Rheumatoid Arthritis (RA). Currently, there are 4 anti-TNF medications available in the UK that are taken as injections. However, in order to be eligible for anti-TNF treatment patients with RA must have an aggressive and active form of the disease and be shown to respond adequately to therapy.
Despite the severity of disease, patients with RA may not take their medication as prescribed all the time (so called non-adherence) for a number of reasons. It could be that patients who don’t take their medication as prescribed don’t feel need it, because their arthritis is less active. Conversely, non-adherence may lead to more active disease. Surprisingly, no studies had previously investigated how non-adherence to anti-TNF medication affects treatment response.
What we found?
We sought to investigate how often patients take their anti-TNF as prescribed and whether those who do not take their medication as prescribed respond to treatment less well.
Patients with severe and active RA were recruited through the Biologics in Rheumatoid Arthritis Genetics and Genomics Study Syndicate (BRAGGSS). They were asked to complete a questionnaire after being reassured that their doctors would not be informed of individual results. A novel question was included to ascertain whether the previous dose of anti-TNF was taken as agreed with their healthcare professional. Analysis was done to determine whether self-reported adherence affected treatment response at 6 months.
Why is this important? What is the benefit to patients?
The research revealed that 27% of patients did not take their medication as advised over the first 6 months of treatment and that these patients responded less well overall. The findings are important and reinforce the need for regular planned, non-judgmental discussions between doctor, nurses and patients, to explore how well they are getting on with their anti-TNF injections. If non-adherence is identified, reasons should be explored and addressed because it affects how well patients will respond to their medication.
(Bluett, J., Morgan, C., BRAGGSS, B., Thurston, L., Plant, D., Hyrich, K., Morgan, A., Wilson, A., Isaacs, J., Cordingley, L. & Barton, A (2014). Impact of inadequate adherence on response to subcutaneously administered anti-tumour necrosis factor drugs: results from the Biologics in Rheumatoid Arthritis Genetics and Genomics Study Syndicate cohort. Rheumatology (Oxford), eScholarID:234413 | PMID:25213131 | DOI:10.1093/rheumatology/keu358)