Study: Using Biologics Early in Patients With Pediatric Crohn Disease Improves Linear Growth

Conventionally, treatment for pediatric Crohn disease (CD) has focused on inducing remission with corticosteroids and maintaining remission with immunomodulators. Those patients who are refractory or intolerant to such a treatment approach are sometimes considered candidates for treatment with infliximab (an approach known as “step-up” therapy), but data on the use of early infliximab treatment in pediatric patients with CD have thus far been limited.

Information about growth failure in pediatric patients with CD has also been limited, though growth failure is recognized as a characteristic of the disease; proposed factors contributing to the problem are chronic undernutrition and the presence of inflammatory cytokines secreted from the intestine. Use of corticosteroids also increases the risk of growth failure.

A newly published retrospective study, appearing in Gut and Liver, sought to evaluate the impact of different treatment approaches on linear growth of pediatric patients with CD, and found that patients who received a combination therapy with infliximab and azathioprine early on had significantly increased linear growth compared to patients whose therapy was stepped up.

A total of 33 patients were included in the study; 16 had been allocated to the step-up group and 17 to the early combined immunosuppression group. Patients in the step-up group received an oral corticosteroid dose of 1 mg/kg daily for induction therapy, which was tapered over 8 weeks, and oral azathioprine and mesalazine for maintenance therapy (infliximab could be added in this group if necessary to maintain clinical remission). The early combined immunosuppression group received infliximab at infused doses of 5 mg/kg at weeks 0, 2, and 6 for induction, and every 8 weeks thereafter. Patients in this group initiated azathioprine at daily doses of 0.5 to 1 mg/kg, and doses were adjusted as required.

Z-scores for height (which measure children’s stature for age) for the 2 groups were as follows at 1, 2, and 3 years after diagnosis:

• —0.20, –0.35, –0.34 for the step-up group
• —0.59, –0.25, and 0.04 for the early combined immunosuppression group

“Our study showed that an early combined immunosuppression strategy was superior to step-up strategy in improving long-term height z-scores,” write the authors, who add that “long-term restoration of linear growth was superior in the early combined immunosuppression when compared from diagnosis.” The authors conclude that early introduction of biologics at the time of diagnosis with pediatric CD should be considered in terms of improving linear growth.