13D Filing: RA Capital Management and Solid Biosciences Inc (SLDB)

The Reporting Persons acquired the Common
Stock reported herein for investment purposes and not with an intent, purpose or effect of changing control of the Issuer. Although
the Reporting Persons currently have no plan or proposal to acquire any additional Common Stock or to dispose of any of the Common
Stock reported herein, the Reporting Persons may acquire additional Common Stock from time to time or dispose of Common Stock they
beneficially own, consistent with their investment purposes and in amounts to be determined by the Reporting Persons based upon
a number of factors, including, without limitation, their ongoing assessment of the Issuer’s business prospects, prevailing market
conditions, the availability of other investment opportunities, and/or other considerations.

In addition, consistent with their investment
purpose, the Reporting Persons may engage in communications with persons associated with the Issuer, including shareholders of
the Issuer, officers of the Issuer and/or members of the board of directors of the Issuer, to discuss matters regarding the Issuer,
including but not limited to its operations and strategic direction. Mr. Rajeev Shah, a portfolio manager and managing director
of RA Capital, currently serves as a director of the Issuer and therefore will engage in regular discussions with the Issuer’s
board of directors and management as part of his duties as a director.

The Reporting Persons have no plans or
proposals that relate to, or could result in, any of the matters referred to in paragraphs (a) through (j), inclusive, of the instructions
to Item 4 of Schedule 13D.

The Reporting Persons may, however, change
their purpose and formulate and implement plans or proposals with respect to the Issuer at any time and from time to time. Any
such action may be made by the Reporting Persons alone or in conjunction with other shareholders, potential acquirers, financing
sources and/or other third parties and could include one or more purposes, plans or proposals that relate to or would result in
actions required to be reported herein in accordance with Item 4 of Schedule 13D.

(a) and (b) See Items 7-11 of the cover
pages and Item 2 above.

(c) The following table lists the Reporting
Persons’ transactions in Common Stock that were effected during the sixty day period prior to the filing of this Schedule
13D: