---
schema_version: "secwatch.filing_event.v1"
accession: "0001193125-25-003214"
form_type: "8-K"
ticker: "VIR"
cik: "0001706431"
company_name: "Vir Biotechnology, Inc."
filed_at: "2025-01-08T23:59:59+00:00"
generated_at: "2026-05-28T06:52:29.416356+00:00"
event_type: "other_material"
sentiment: "positive"
materiality_score: 0.75
calibrated_materiality_score: 0.75
confidence: "high"
source: SEC EDGAR
---

# Vir Biotech reports encouraging Phase 1 data: 50% tumor shrinkage (VIR-5818), 58% PSA50 (VIR-5500)

## Summary
- VIR-5818 (HER2): 50% (10/20) tumor shrinkage at doses ≥400 µg/kg; cPR in 33% (2/6) HER2+ CRC.
- VIR-5500 (PSMA mCRPC): PSA declines in 100% (12/12) and PSA50 response in 58% (7/12) at first dose ≥120 µg/kg.
- Safety: No dose-limiting CRS; max grade 2 CRS; MTD not reached for either TCE; dosing up to 1000 µg/kg.
- PRO-XTEN masking technology shows minimal systemic unmasking; half-life 6-10 days enabling Q3W dosing.
- Phase 1 trials ongoing; dose escalation continues; company to hold investor call Jan 8, 2025.

## SEC filing metadata
- accession: 0001193125-25-003214
- form_type: 8-K
- ticker: VIR
- cik: 0001706431
- company_name: Vir Biotechnology, Inc.
- filed_at: 2025-01-08T23:59:59+00:00
- event_type: other_material
- sentiment: positive
- materiality_score: 0.75
- calibrated_materiality_score: 0.75
- confidence: high
- sec_items: 7.01, 8.01, 9.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/1706431/000119312525003214/0001193125-25-003214-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/1706431/000119312525003214/d887412d8k.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0001193125-25-003214
- JSON: https://secwatch.observer/filing/0001193125-25-003214.json
- Plain text: https://secwatch.observer/filing/0001193125-25-003214.txt

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