---
schema_version: "secwatch.filing_event.v1"
accession: "0001193125-26-202389"
form_type: "8-K"
ticker: "CABA"
cik: "0001759138"
company_name: "Cabaletta Bio, Inc."
filed_at: "2026-05-04T23:59:59+00:00"
generated_at: "2026-05-14T23:57:16.141906+00:00"
event_type: "other_material"
sentiment: "positive"
materiality_score: 0.65
calibrated_materiality_score: 0.65
confidence: "high"
source: SEC EDGAR
---

# Cabaletta Bio reports rese-cel activity without preconditioning in 4 PV patients; ASGCT presentation May 14

## Summary
- 2 of 4 refractory PV patients on rese-cel at lowest dose showed compelling clinical activity through 6 months without preconditioning.
- Complete peripheral B-cell elimination observed in 3 of 4 patients; 3 of 4 remained off all immunomodulators and steroids as of April 2, 2026.
- Safety: 1 of 4 patients had Grade 1 CRS; no ICANS of any grade. Additional patients enrolled at higher dose in RESET-PV.
- RESET-SLE trial initial dose cohort (no preconditioning) fully enrolled; initial data expected first half 2026.
- Data to be presented at ASGCT 2026 Annual Meeting on May 14, 2026; higher dose durability data anticipated H2 2026.

## SEC filing metadata
- accession: 0001193125-26-202389
- form_type: 8-K
- ticker: CABA
- cik: 0001759138
- company_name: Cabaletta Bio, Inc.
- filed_at: 2026-05-04T23:59:59+00:00
- event_type: other_material
- sentiment: positive
- materiality_score: 0.65
- calibrated_materiality_score: 0.65
- confidence: high
- sec_items: 8.01, 9.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/1759138/000119312526202389/0001193125-26-202389-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/1759138/000119312526202389/d110169d8k.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0001193125-26-202389
- JSON: https://secwatch.observer/filing/0001193125-26-202389.json
- Plain text: https://secwatch.observer/filing/0001193125-26-202389.txt

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