---
schema_version: "secwatch.filing_event.v1"
accession: "0000950170-25-074428"
form_type: "8-K"
ticker: "CRSP"
cik: "0001674416"
company_name: "CRISPR Therapeutics AG"
filed_at: "2025-05-19T23:59:59+00:00"
generated_at: "2026-05-21T01:48:22.571611+00:00"
event_type: "m_and_a"
sentiment: "positive"
materiality_score: 0.8
calibrated_materiality_score: 0.8
confidence: "high"
source: SEC EDGAR
---

# CRISPR Therapeutics enters collaboration with Sirius on FXI-targeting siRNA; positive Phase 1 data

## Summary
- Upfront consideration: $70M in common shares + $25M cash to Sirius for co-development of FXI-targeting siRNA SRSD107.
- Potential milestones: up to $340M for opt-out and up to $87.5M for development/regulatory; royalties mid-single to low-double digit.
- Phase 1: single doses well tolerated, >93% reduction in FXI levels and activity, sustained up to six months post-dosing.
- Phase 2 trial initiated for prevention of venous thromboembolism in patients undergoing total knee arthroplasty.
- Company has options to exclusively license Sirius siRNA technology for up to two additional targets; $10M option fee per target.

## SEC filing metadata
- accession: 0000950170-25-074428
- form_type: 8-K
- ticker: CRSP
- cik: 0001674416
- company_name: CRISPR Therapeutics AG
- filed_at: 2025-05-19T23:59:59+00:00
- event_type: m_and_a
- sentiment: positive
- materiality_score: 0.8
- calibrated_materiality_score: 0.8
- confidence: high
- sec_items: 1.01, 8.01, 9.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/1674416/000095017025074428/0000950170-25-074428-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/1674416/000095017025074428/crsp-20250519.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0000950170-25-074428
- JSON: https://secwatch.observer/filing/0000950170-25-074428.json
- Plain text: https://secwatch.observer/filing/0000950170-25-074428.txt

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