X0508 4 2025-02-18 1 0001707502 Solid Biosciences Inc. SLDB 0001535978 Adage Capital Management, L.P. 200 CLARENDON STREET, 52ND FLOOR BOSTON MA 02116 0 0 1 0 0001403404 Atchinson Robert 200 CLARENDON STREET 52ND FLOOR BOSTON MA 02116 0 0 1 0 0001403413 Gross Phillip 200 CLARENDON STREET 52ND FLOOR BOSTON MA 02116 0 0 1 0 0 Common Stock, $0.001 par value per share 2025-02-18 4 P 0 252545 7.56 A 4248084 I See footnotes The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $7.22 to $7.75, inclusive. The Reporting Persons undertake to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth herein. The securities to which this filing relates are held directly by Adage Capital Partners, L.P., a Delaware limited partnership ("ACP"). Adage Capital Management, L.P., a Delaware limited partnership ("ACM"), serves as the investment manager of ACP and as such has discretion over the portfolio securities held by ACP. Robert Atchinson and Phillip Gross are the managing members of (i) Adage Capital Advisors, L.L.C., a Delaware limited liability company, managing member of Adage Capital Partners GP, L.L.C., a Delaware limited liability company, general partner of ACP and (ii) Adage Capital Partners LLC, a Delaware limited liability company, general partner of ACM. Each of the Reporting Persons disclaims beneficial ownership of the securities reported herein for purposes of Section 16 of the Securities and Exchange Act of 1934, as amended, except as to such extent of such Reporting Person's pecuniary interest in the securities, if any. /s/ Adage Capital Management, L.P.; By: its general partner Adage Capital Partners LLC; By its managing member Robert Atchinson 2025-02-19 /s/ Robert Atchinson 2025-02-19 /s/ Phillip Gross 2025-02-19