---
schema_version: "secwatch.filing_event.v1"
accession: "0001193125-23-220087"
form_type: "8-K"
ticker: "CTMX"
cik: "0001501989"
company_name: "CytomX Therapeutics, Inc."
filed_at: "2023-08-24T23:59:59+00:00"
generated_at: "2026-06-11T04:07:51.654836+00:00"
event_type: "other_material"
sentiment: "neutral"
materiality_score: 0.7
calibrated_materiality_score: 0.7
confidence: "high"
source: SEC EDGAR
---

# CytomX Therapeutics regains exclusive worldwide rights to ADC CX-2029 from AbbVie

## Summary
- Regained full worldwide rights to develop CX-2029, a CD71-targeting conditionally activated antibody drug conjugate.
- AbbVie eligible for tiered sales royalties on CX-2029 ranging from low-to-mid single digit percentages.
- CytomX to pay Seagen potential future milestones and tiered sales royalties (mid-to-high single digits) for linker payload tech.
- Transition Agreement supersedes the terminated 2016 CD71 Co-Development and License Agreement with AbbVie.

## SEC filing metadata
- accession: 0001193125-23-220087
- form_type: 8-K
- ticker: CTMX
- cik: 0001501989
- company_name: CytomX Therapeutics, Inc.
- filed_at: 2023-08-24T23:59:59+00:00
- event_type: other_material
- sentiment: neutral
- materiality_score: 0.7
- calibrated_materiality_score: 0.7
- confidence: high
- sec_items: 1.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/1501989/000119312523220087/0001193125-23-220087-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/1501989/000119312523220087/d489987d8k.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0001193125-23-220087
- JSON: https://secwatch.observer/filing/0001193125-23-220087.json
- Plain text: https://secwatch.observer/filing/0001193125-23-220087.txt

## Key facts
- Material Agreements
  CytomX Therapeutics, Inc. entered into Transition Agreement with AbbVie Global Enterprises Ltd. valued at royalties low-to-mid single digit percentages; milestones and royalties mid-to-high single digit per (effective 2023-08-22).
  - Action: entry
  - Agreement: license
  - Counterparty: AbbVie Global Enterprises Ltd.
  - Value: royalties low-to-mid single digit percentages; milestones and royalties mid-to-high single digit per
  - Effective: 2023-08-22
  source text: On August 22, 2023, CytomX Therapeutics, Inc. (the “Company”) entered into a Transition Agreement (the “Transition Agreement”) with AbbVie Global Enterprises Ltd. (“AbbVie”), pursuant to which the Company regained exclusive worldwide rights to develop CX-2029, a CD71-targeting conditionally activated antibody drug conjugate.
  evidence_url: https://www.sec.gov/Archives/edgar/data/1501989/000119312523220087/0001193125-23-220087-index.htm

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