144 0001529297 XXXXXXXX LIVE 0001707502 Solid Biosciences Inc. 001-38360 500 Rutherford Avenue Charlestown MA 02129 (617)-337-4680 Howton David T Officer Common Stock ETRADE FINANCIAL CORPORATION

3 EDISON DRIVE ALPHARETTA GA 30005

5072 28396.05 39954607 12/03/2024 NASDAQ Common Stock 12/02/2024 Settlement of vested restricted stock units Issuer N 5072 12/02/2024 Compensation Y The sales reported on this Form 144 represent shares required to be sold by the Reporting Person to cover tax withholding obligations in connection with the vesting and settlement of restricted stock units. These sales do not represent discretionary trades by the Reporting Person. 12/04/2024 /s/ David Tyronne Howton