X0508 4 2026-01-21 0001759138 Cabaletta Bio, Inc. CABA 0001881529 Gerard Michael C/O CABALETTA BIO, INC. 2929 ARCH STREET, SUITE 600 PHILADELPHIA PA 19104 false true false false General Counsel false Common Stock 2026-01-21 4 P false 6600 2.2696 A 6600 D The price reported in Column 4 is a weighted average price. These shares were purchased at prices ranging from $2.269 to $2.2699, inclusive. The reporting person has provided to the Issuer, and undertakes to provide any security holder of the Issuer or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares purchased at each separate price within the range set forth in this footnote. By: /s/ Michael Gerard 2026-01-21