---
schema_version: "secwatch.filing_event.v1"
accession: "0001558370-25-000823"
form_type: "8-K"
ticker: "XLO"
cik: "0001840233"
company_name: "Xilio Therapeutics, Inc."
filed_at: "2025-02-12T23:59:59+00:00"
generated_at: "2026-05-26T23:00:08.068336+00:00"
event_type: "other_material"
sentiment: "positive"
materiality_score: 0.85
calibrated_materiality_score: 0.85
confidence: "high"
source: SEC EDGAR
---

# Xilio signs AbbVie deal: $52M upfront, up to $2.1B milestones for masked T-cell engagers

## Summary
- Upfront $52M ($42M cash + $10M equity at $2.30/shr); AbbVie gets options for 4 masked TCE programs and license for masked antibody.
- Contingent payments up to ~$2.1B in option fees and milestones plus tiered mid-to-high single-digit royalties.
- Xilio announces three wholly-owned preclinical masked TCE programs targeting PSMA, CLDN18.2, STEAP1 with candidate nomination timelines through 2027.
- Cash runway extended into Q1 2026 with upfront payments; additional milestones require further capital.
- Collaboration validates Xilio's tumor-activation platform; CEO highlights potential to improve TCE tolerability.

## SEC filing metadata
- accession: 0001558370-25-000823
- form_type: 8-K
- ticker: XLO
- cik: 0001840233
- company_name: Xilio Therapeutics, Inc.
- filed_at: 2025-02-12T23:59:59+00:00
- event_type: other_material
- sentiment: positive
- materiality_score: 0.85
- calibrated_materiality_score: 0.85
- confidence: high
- sec_items: 1.01, 3.02, 7.01, 8.01, 9.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/1840233/000155837025000823/0001558370-25-000823-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/1840233/000155837025000823/xlo-20250210x8k.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0001558370-25-000823
- JSON: https://secwatch.observer/filing/0001558370-25-000823.json
- Plain text: https://secwatch.observer/filing/0001558370-25-000823.txt

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