New consensus statements for therapeutic drug monitoring in patients receiving anti-TNF agents for their IBD will help optimise patient outcomes and rationalise use of the costly agents.
The panel of Australian, New Zealand, US and Canadian experts agreed on 22 of the 24 statements drafted after an extensive literature review and modified Delphi process.
They agreed that therapeutic drug monitoring had most utility following successful treatment induction, when considering drug holidays and in treatment failure.
Lead author Professor Rupert Leong, from the Concord Hospital IBD Service, told the limbic monitoring was appropriate soon after successful indication to confirm a therapeutic drug level but not periodically during clinical remission unless the findings would affect management.
Therapeutic drug monitoring could also guide clinical decision-making in situations of primary non-response and secondary loss of response.
The panel determined dose escalation should only occur after confirming active inflammation.
“A lot of doctors are giving increased doses when patients complain of symptoms without finding out why. We need to have objective measures of inflammation such as faecal calprotectin, sigmoidoscopy or colonoscopy,” Professor Leong said.
The panel agreed adherent patients with confirmed active inflammation, sub-therapeutic drug trough levels and no detectable anti-drug antibodies should have dose escalation of their anti-TNF.
However patients with confirmed inflammation and therapeutic drug trough levels were more likely to have pharmacodynamic failure and should be switched out of class.