---
schema_version: "secwatch.filing_event.v1"
accession: "0001193125-21-354690"
form_type: "8-K"
ticker: "KLRS"
cik: "0001754068"
company_name: "Kalaris Therapeutics, Inc."
filed_at: "2021-12-13T23:59:59+00:00"
generated_at: "2026-06-28T01:46:41.989057+00:00"
event_type: "other_material"
sentiment: "positive"
materiality_score: 0.75
calibrated_materiality_score: 0.75
confidence: "high"
source: SEC EDGAR
---

# AlloVir announces positive preliminary Phase 2 data for posoleucel in virus prevention in high-risk allo-HCT patients

## Summary
- No end-organ viral disease observed in 23 high-risk allo-HCT patients receiving posoleucel.
- Only 3 of 138 possible clinically significant infections occurred; 11 of 13 patients through Week 14 free of infection.
- FDA agreed in principle to advance to Phase 3 registrational trial expected to start in 1H 2022.
- Posoleucel targeting six viruses: AdV, BKV, CMV, EBV, HHV-6, and JCV.

## SEC filing metadata
- accession: 0001193125-21-354690
- form_type: 8-K
- ticker: KLRS
- cik: 0001754068
- company_name: Kalaris Therapeutics, Inc.
- filed_at: 2021-12-13T23:59:59+00:00
- event_type: other_material
- sentiment: positive
- materiality_score: 0.75
- calibrated_materiality_score: 0.75
- confidence: high
- sec_items: 7.01, 8.01, 9.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/1754068/000119312521354690/0001193125-21-354690-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/1754068/000119312521354690/d261161d8k.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0001193125-21-354690
- JSON: https://secwatch.observer/filing/0001193125-21-354690.json
- Plain text: https://secwatch.observer/filing/0001193125-21-354690.txt

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