---
schema_version: "secwatch.filing_event.v1"
accession: "0001193125-23-301777"
form_type: "8-K"
ticker: "KLRS"
cik: "0001754068"
company_name: "Kalaris Therapeutics, Inc."
filed_at: "2023-12-22T23:59:59+00:00"
generated_at: "2026-06-07T08:07:56.359655+00:00"
event_type: "other_material"
sentiment: "negative"
materiality_score: 0.85
calibrated_materiality_score: 0.85
confidence: "high"
source: SEC EDGAR
---

# AlloVir discontinues all three Phase 3 posoleucel trials after DSMB futility analyses

## Summary
- Three Phase 3 trials for prevention, hemorrhagic cystitis, and adenovirus stopped after separate DSMBs deemed each unlikely to meet primary endpoints.
- No safety concerns observed; discontinuation based on pre-planned futility analyses.
- Company to prioritize capital preservation; held $213.3M cash and equivalents as of Sep 30, 2023.
- AlloVir will review strategic alternatives including merger, sale, or licensing of assets.

## SEC filing metadata
- accession: 0001193125-23-301777
- form_type: 8-K
- ticker: KLRS
- cik: 0001754068
- company_name: Kalaris Therapeutics, Inc.
- filed_at: 2023-12-22T23:59:59+00:00
- event_type: other_material
- sentiment: negative
- materiality_score: 0.85
- calibrated_materiality_score: 0.85
- confidence: high
- sec_items: 7.01, 8.01, 9.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/1754068/000119312523301777/0001193125-23-301777-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/1754068/000119312523301777/d671953d8k.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0001193125-23-301777
- JSON: https://secwatch.observer/filing/0001193125-23-301777.json
- Plain text: https://secwatch.observer/filing/0001193125-23-301777.txt

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