---
schema_version: "secwatch.filing_event.v1"
accession: "0001437749-23-028296"
form_type: "8-K"
ticker: "OMER"
cik: "0001285819"
company_name: "OMEROS CORP"
filed_at: "2023-10-16T23:59:59+00:00"
generated_at: "2026-06-09T23:07:28.002086+00:00"
event_type: "other_material"
sentiment: "negative"
materiality_score: 0.85
calibrated_materiality_score: 0.85
confidence: "high"
source: SEC EDGAR
---

# Omeros Phase 3 ARTEMIS-IGAN trial fails primary endpoint; narsoplimab BLA in IgAN discontinued

## Summary
- Narsoplimab did not achieve statistically significant reduction in proteinuria at 36 weeks vs placebo (24-hour UPE >2 g/day).
- Placebo group showed markedly greater proteinuria reduction than in other IgA nephropathy trials.
- Company will not submit BLA for narsoplimab in IgAN and is discontinuing the ARTEMIS-IGAN trial.
- Funds redirected to OMS906 (alternative pathway inhibitor) Phase 2/3 programs and narsoplimab BLA resubmission for HSCT-TMA.
- Narsoplimab was generally well tolerated with no new safety concerns.

## SEC filing metadata
- accession: 0001437749-23-028296
- form_type: 8-K
- ticker: OMER
- cik: 0001285819
- company_name: OMEROS CORP
- filed_at: 2023-10-16T23:59:59+00:00
- event_type: other_material
- sentiment: negative
- materiality_score: 0.85
- calibrated_materiality_score: 0.85
- confidence: high
- sec_items: 8.01, 9.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/1285819/000143774923028296/0001437749-23-028296-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/1285819/000143774923028296/omer20231012c_8k.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0001437749-23-028296
- JSON: https://secwatch.observer/filing/0001437749-23-028296.json
- Plain text: https://secwatch.observer/filing/0001437749-23-028296.txt

This AI-assisted summary is a reading aid. Review the linked SEC EDGAR filing before relying on any specific claim.