---
schema_version: "secwatch.filing_event.v1"
accession: "0001125345-24-000065"
form_type: "8-K"
ticker: "MGNX"
cik: "0001125345"
company_name: "MACROGENICS INC"
filed_at: "2024-04-03T23:59:59+00:00"
generated_at: "2026-06-04T02:43:23.455882+00:00"
event_type: "other_material"
sentiment: "neutral"
materiality_score: 0.7
calibrated_materiality_score: 0.7
confidence: "high"
source: SEC EDGAR
---

# MacroGenics Phase 2 TAMARACK safety data shows improved tolerability at lower vobra duo doses

## Summary
- Drug interruption rate 12.6% vs 58.5% at 12 weeks in Phase 1; discontinuation 5.3% vs 14.6%.
- No fatal AEs; most common TEAEs: asthenia (40.7%), nausea (27.7%), fatigue (20.3%).
- ASCO abstract not accepted; plan to share updated interim safety + efficacy by May 31, 2024.
- rPFS primary endpoint data expected Fall 2024; IDMC recommended study continue unchanged.
- Enrolled 182 mCRPC patients across 2.0 and 2.7 mg/kg Q4W dose arms; 85.7% still on treatment.

## SEC filing metadata
- accession: 0001125345-24-000065
- form_type: 8-K
- ticker: MGNX
- cik: 0001125345
- company_name: MACROGENICS INC
- filed_at: 2024-04-03T23:59:59+00:00
- event_type: other_material
- sentiment: neutral
- materiality_score: 0.7
- calibrated_materiality_score: 0.7
- confidence: high
- sec_items: 8.01, 9.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/1125345/000112534524000065/0001125345-24-000065-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/1125345/000112534524000065/mgnx-20240403.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0001125345-24-000065
- JSON: https://secwatch.observer/filing/0001125345-24-000065.json
- Plain text: https://secwatch.observer/filing/0001125345-24-000065.txt

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