Current Report · Items 8.01 · 8-K

Cabaletta Bio, Inc.

CABANASDAQEQUITYCurrent

Other Events

Filed Sep 14, 2026Accepted Sep 14, 2026, 8:00 AM EDTCIK 1759138Accession 0001759138-26-000041

Company context

Cabaletta Bio (Nasdaq: CABA) is a late-stage clinical biotechnology company focused on developing and launching curative targeted cell therapies designed specifically for patients with autoimmune diseases. Cabaletta’s lead product candidate, rese-cel, is an investigational 4-1BB-containing fully human CD19-CAR T cell therapy being advanced across the RESET™ (REstoring SElf-Tolerance) clinical development program spanning multiple therapeutic areas, including rheumatology, neurology and dermatology. Cabaletta Bio’s headquarters and labs are located in Philadelphia, PA. For more information, visit www.cabalettabio.com and connect with us on LinkedIn.

Current securities

CABANASDAQ · EQUITY · Current

Recent company filings

Disclosure sections

Items 8.01

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Item 8.01Item 8.01 - Other Events

Item 8.01 Other Events. In connection with Cabaletta Bio’s (the “Corporation”) June 2025 underwritten public offering, the Corporation issued 53,090,190 common stock warrants (the “Common Stock Warrants”) that had an exercise price of $2.50 per whole share of its common stock and an expiration date of September 12, 2026 (the “Expiration Date”). From issuance through June 30, 2026, 5,275,100 Common Stock Warrants were exercised resulting in aggregate gross proceeds of approximately $13.2 million. From July 1, 2026 through the Expiration Date, 46,011,900 Common Stock Warrants were exercised resulting in aggregate gross proceeds of approximately $115.0 million. The aggregate gross proceeds from exercises of the Common Stock Warrants from issuance through the Expiration Date is approximately $128.2 million.