Impact of prior irregular infliximab dosing on performance of long-term infliximab maintenance therapy in Crohn's disease.

Background: Infliximab is efficacious in the management of moderate to severe Crohn's disease (CD). There are limited data regarding performance of infliximab in patients who require reinitiation of maintenance dosing following previous irregular exposure.

Methods: This was a retrospective, observational study of CD patients treated with maintenance infliximab beyond 3 years. Maintenance infliximab infusion regimens were categorized as scheduled maintenance (SM) (maintenance infusions q < or =8 weeks after loading) or prior irregular (PI) (no loading, gap in therapy >8 weeks prior to or during maintenance therapy). We examined differences in need for medical and surgical hospitalizations as well as associated healthcare costs between the 2 groups.

Results: In all, 104 CD patients met criteria for 3-year maintenance infliximab treatment (SM n = 64; PI n = 40). The rates of CD-related surgeries (60.9% and 55.0%, P = not significant [N.S.]) and medical hospitalizations (35.9% and 37.5%, P = N.S.) prior to infliximab initiation was similar between the 2 groups. However, the rate of medical (26.5% versus 47.5%, P = 0.035) and surgical hospitalizations (21.8% versus 48.7%, P = 0.009) were significantly lower in the SM compared to the PI group. During the third year of treatment the excess costs per patient for the PI group compared to the SM group amounted to $11,464 in spite of both cohorts being on SM therapy.

Conclusions: Patients who begin and continue an uninterrupted maintenance dosing regimen had a lower incidence of hospitalization and surgery than those who received an irregular or interrupted regimen prior to beginning an SM regimen.