Anti-TNF-associated immunogenicity: use a retroactive drug but a proactive approach

We read the study by Roblin et al with interest.1 Given that prior antitumour necrosis factor (anti-TNF) monotherapy failure is frequently associated with antibody development to a second anti-TNF within 24 months,2 it is our practice, to (re)introduce immunomodulator cotherapy with the second anti-TNF to reduce immunogenicity and improve treatment persistence.3 4 Roblin et al ’s findings support this concept, reinforcing the value of thiopurine cotherapy to reduce immunogenicity with the second anti-TNF following immune-mediated failure of first-line anti-TNF monotherapy. Moreover, they demonstrated that combination therapy was less frequently associated with clinical relapse, clinical failure and pharmacokinetic failure (ie, undetectable anti-TNF trough levels with high antidrug antibodies) than anti-TNF monotherapy. These data also imply a longer (24 months) duration of combination therapy may be required for those at increased risk of immunogenicity than previously (6–12 months) suggested.5 In retrospect, perhaps continuing combination therapy ab initio, particularly for infliximab where combination …