---
schema_version: "secwatch.filing_event.v1"
accession: "0000950170-25-004523"
form_type: "8-K"
ticker: "MREO"
cik: "0001719714"
company_name: "Mereo BioPharma Group plc"
filed_at: "2025-01-13T23:59:59+00:00"
generated_at: "2026-05-28T03:37:01.618701+00:00"
event_type: "other_material"
sentiment: "positive"
materiality_score: 0.6
calibrated_materiality_score: 0.6
confidence: "high"
source: SEC EDGAR
---

# Mereo BioPharma: setrusumab Phase 3 Orbit 2nd interim analysis mid-2025; alvelestat gets positive EMA orphan opinion

## Summary
- Phase 3 Orbit study of setrusumab in OI progressing to second interim analysis expected mid-2025; final analysis possible Q4 2025.
- Alvelestat receives positive EMA COMP opinion for Orphan Designation; European Commission final decision expected Q1 2025.
- Cash runway reaffirmed into 2027, funding through multiple key inflection points including setrusumab milestones.
- Cosmic study in OI patients aged 2 to <7 years continuing; data will be evaluated with Orbit analyses.

## SEC filing metadata
- accession: 0000950170-25-004523
- form_type: 8-K
- ticker: MREO
- cik: 0001719714
- company_name: Mereo BioPharma Group plc
- filed_at: 2025-01-13T23:59:59+00:00
- event_type: other_material
- sentiment: positive
- materiality_score: 0.6
- calibrated_materiality_score: 0.6
- confidence: high
- sec_items: 7.01, 9.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/1719714/000095017025004523/0000950170-25-004523-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/1719714/000095017025004523/mreo-20250112.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0000950170-25-004523
- JSON: https://secwatch.observer/filing/0000950170-25-004523.json
- Plain text: https://secwatch.observer/filing/0000950170-25-004523.txt

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