---
schema_version: "secwatch.filing_event.v1"
accession: "0001125345-23-000021"
form_type: "8-K"
ticker: "MGNX"
cik: "0001125345"
company_name: "MACROGENICS INC"
filed_at: "2023-02-14T23:59:59+00:00"
generated_at: "2026-06-19T13:10:18.435131+00:00"
event_type: "other_material"
sentiment: "positive"
materiality_score: 0.65
calibrated_materiality_score: 0.65
confidence: "high"
source: SEC EDGAR
---

# MacroGenics reports preliminary Phase 1 lorigerlimab data; 28.6% PSA50 in mCRPC

## Summary
- 12 of 42 mCRPC patients (28.6%) achieved ≥50% PSA reduction; 9 of 42 (21.4%) achieved ≥90% PSA reduction.
- 9 of 35 evaluable patients (25.7%) had confirmed partial responses; median duration 4.6 months.
- TRAEs in 86.6% of patients; grade ≥3 TRAEs in 34.6%; 24.4% discontinued due to AEs; no fatal TRAEs.
- Company plans to initiate Phase 2 study in mCRPC in 2023.
- Median prior therapies: 2; 83% had prior docetaxel, 81% prior androgen receptor antagonist.

## SEC filing metadata
- accession: 0001125345-23-000021
- form_type: 8-K
- ticker: MGNX
- cik: 0001125345
- company_name: MACROGENICS INC
- filed_at: 2023-02-14T23:59:59+00:00
- event_type: other_material
- sentiment: positive
- materiality_score: 0.65
- calibrated_materiality_score: 0.65
- confidence: high
- sec_items: 8.01, 9.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/1125345/000112534523000021/0001125345-23-000021-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/1125345/000112534523000021/mgnx-20230213.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0001125345-23-000021
- JSON: https://secwatch.observer/filing/0001125345-23-000021.json
- Plain text: https://secwatch.observer/filing/0001125345-23-000021.txt

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