Infliximab is effective maintenance for moderate to severe Crohn's disease. 

However, problems with immunogenicity and decreased efficacy often complicate long-term use. 

Durability of infliximab maintenance therapy over multiple years has not been defined. 

Dr Jason Gonzaga and colleagues from Pennsylvania, USA performed a retrospective, observational study of Crohn's disease  patients who received maintenance infliximab for 1 year with the intention of ongoing maintenance. 

Patients were categorized into those who either discontinued treatment or continued maintenance therapy. 

The team examined the impact of demographic, clinical characteristics, and prior episodic exposure on long-term durability of infliximab therapy and also examined the reasons for discontinuation of therapy. 

The researchers reported that a total of 153 Crohn's disease patients received maintenance infliximab treatment beyond 1 year, and 27% ultimately discontinued treatment. 

The mean duration of maintenance treatment at the time of discontinuation was 42 months compared to a follow-up period of 49 months in the cohort continuing therapy.

The main reasons for discontinuation were allergy/adverse reaction in 44%, and decreased efficacy in 38%. 

Use of concomitant immunosuppression was similar between the 2 groups. 

However, the discontinued group had a higher rate of prior episodic dosing compared to Crohn's disease patients who continued maintenance, while there was no difference in the rate of intensified dosing. 

Dr Gonzaga's team concluded, "One-quarter of Crohn's disease patients on long-term infliximab maintenance discontinued treatment."

"A history of prior episodic dosing was significantly associated with infliximab discontinuation, despite concomitant immunosuppression."

"These data emphasize the need for optimization of infliximab for successful long-term management."