Xencor reports Phase 1 data for XmAb942 showing 74-day half-life, Phase 2b on track

Filed May 5, 2026 · Period ending May 4, 2026 · ~2 min read

Key Changes

• high

  Final Phase 1 results for XmAb942 showed an estimated terminal half-life of 74.1 days, enabling 12-week dosing intervals in maintenance treatment. No serious or severe adverse events occurred; treatment-emergent adverse events were comparable to placebo (75% vs 69%).

  Exhibit 99.2 verify on EDGAR →
• high

  Phase 2b XENITH-UC study enrollment remains on track, targeting ~220 patients with moderate to severe ulcerative colitis. Blinded interim analysis expected around year-end 2026, with full 12-week primary endpoint results in second half 2027.

  Exhibit 99.2 verify on EDGAR →
• medium

  At Phase 2b dose levels, 25% of Phase 1 participants tested positive for anti-drug antibodies with 0% having neutralizing antibodies. Across all doses, ADA positivity was 57% with only 2% developing neutralizing antibodies, with no impact on safety or pharmacokinetics.

  Exhibit 99.2 verify on EDGAR →