Introduction: The UNIFI randomized-withdrawal maintenance study evaluated subcutaneous (SC) ustekinumab (UST) in patients (pts) with moderately to severely active ulcerative colitis (UC). Pts who completed the maintenance study (WK44) could enter a long-term extension (LTE) through 220 weeks (wks). We evaluated the effect of UST maintenance therapy on stool frequency & rectal bleeding through 92wks.

Methods: Pts were eligible to dose adjust (PBO to q8w; q12w to q8w; q8w to q8w [sham dose adjustment]) starting at Wk56 and the recorded number of stools and rectal bleeding symptoms for 7 days before each visit. Proportions of pts with Mayo stool frequency subscores of 0 (normal number of stools) or 1 (1-2 stools more than normal) or rectal bleeding subscores of 0 (no blood seen) were evaluated. Absolute stool number was summarized.

Results: Pts in LTE included UST 90 mg q12w: n = 141 and UST 90 mg q8w: n = 143. Absolute stool number in UST q12w and q8w groups were 6.6 & 6.5 stools/day, respectively, at induction baseline and decreased to 2.8 and 2.7, respectively, by maintenance baseline. Reductions achieved at maintenance baseline were maintained at Wk92 (2.7 & 2.2, respectively). At induction baseline, only 12.8% & 18.2% of pts, respectively, had Mayo stool frequency subscores of 0 or 1. By maintenance baseline, 80.9% & 80.4%, respectively, had Mayo stool frequency subscores of 0 or 1, and these were maintained through Wk92 (79.4% & 86.7% at Wk92, respectively). At induction baseline, 9.2% & 7.0%, respectively, had no blood seen in the stool (Mayo rectal bleeding subscore of 0). By maintenance baseline, 87.2% & 84.6%, respectively, had no blood seen in the stool & these were maintained through Wk92 (86.5% & 88.8%) (table).

Conclusions: Among pts in the LTE, reductions in stool frequency and rectal bleeding achieved after IV UST induction were maintained through 2 years of UST SC maintenance. These data support the durability of response to UST in UC.