Biologic dose optimization not needed in UC patients with early nonresponse, high drug clearance

For patients with ulcerative colitis who are receiving vedolizumab, dose optimization may not be required in the presence of early nonresponse to treatment as well as high drug clearance, according to data from the phase IV ENTERPRET study.

ENTERPRET included 278 patients with moderate-to-severe UC who had high drug clearance at week 5 (serum concentration <50 μg/mL) and had no response to standard vedolizumab treatment at week 6. At week 6, eligible patients were randomly assigned to receive vedolizumab at standard dosing (300 mg every 8 weeks) or optimized dosing based on week 5 serum concentration (600 mg at week 6, then 300 mg every 4 weeks; or 600 mg at week 6, then 600 mg every 4 weeks).

Of the patients, 132 (47.5 percent) had a clinical response to treatment at week 6. At week 6, 108 patients received either standard (n=53) or dose-optimized vedolizumab (n=55). Among the patients who showed no response to treatment at week 6, 86.5 percent had high drug clearance.

The primary endpoint of endoscopic improvement at week 30 was achieved in 10 patients (18.9 percent) in the standard-dose group and in eight patients (14.5 percent) in the dose-optimized group. Clinical remission was observed in five patients in each group (9.4 percent and 9.1 percent, respectively).

Clinical response rates were 32.1 percent in the standard-dose group and 30.9 percent in the dose-optimized group.

Safety event rates did not significantly differ between the two treatment groups.

The findings show that a proportion of patients may benefit from continued treatment regardless of the vedolizumab dose received.