secwatch.observer — SEC 8-K summary
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Issuer:     Zenas BioPharma, Inc. (ZBIO)
CIK:        0001953926
Form:       8-K
Filed at:   2026-10-13T10:01:28+00:00
Accession:  0001104659-26-115151
Event type: other_material
Sentiment:  positive
Materiality: 0.62
Item codes: 7.01, 9.01
LLM model:  deepseek-v4.1-flash:cloud@v2

Zenas BioPharma reports Phase 3 INDIGO open-label extension obexelimab data in IgG4-RD
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- 12-month probability of remaining flare-free: 0.93 for adjudication committee-confirmed flares, 0.87 for investigator-determined; median cumulative glucocorticoid rescue dose 0 mg (mean 105 mg)
- Obexelimab significantly reduced cumulative glucocorticoid toxicity versus placebo at week 52 (GTI Cumulative Worsening Score difference -11.4; p=0.021)
- Vaccine sub-study: seroimmunity to influenza in 6 of 7 (86%) and COVID-19 in 4 of 4 (100%) during a treatment-free window averaging 34.6 days, with no disease flares
- Participants (n=7) maintained pre-existing immunity markers after long-term obexelimab treatment: 71% for influenza and 50% for COVID-19
- Data presented at the 6th International Symposium on IgG4-Related Disease, held October 8-10, 2026 in Cambridge, Massachusetts

Source:
  EDGAR index:    https://www.sec.gov/Archives/edgar/data/1953926/000110465926115151/0001104659-26-115151-index.htm
  Primary doc:    https://www.sec.gov/Archives/edgar/data/1953926/000110465926115151/tm2627406d1_8k.htm
  HTML page:      https://secwatch.observer/filing/0001104659-26-115151

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