Summary of Non-Employee Director Compensation Program

The Board of Directors (the “Board”) of Concert Pharmaceuticals, Inc. (the “Company”) has approved the following non-employee director compensation program.

Each non-employee director will receive a cash retainer for service on the Board and for service on each committee of which the director is a member. The Chairman of the Board and the chair of each committee will receive higher retainers for such service. These fees are payable quarterly in arrears. The fees paid to non-employee directors for service on the Board and for service on each committee of the Board of which the director is a member are as follows:

Non-employee directors may elect to receive all or a portion of their cash retainer for the one-year period following each annual meeting of stockholders in the form of a stock option award. The option will be granted on the date of the first Board meeting held after the annual meeting of stockholders that marks the beginning of the one-year period. The number of shares subject to the option will be calculated using the fair value of a share of the Company’s common stock on the date of grant. Each of these options will vest in equal quarterly installments over a one-year period measured from the date of the annual meeting of stockholders that marks the beginning of the one-year period, subject to the director’s continued service as a director, and will become exercisable in full on the date that is one business day prior to the date of the Company’s next annual meeting of stockholders (if earlier than the first anniversary of the annual meeting of stockholders that marks the beginning of the one-year period).

In addition, each new non-employee director elected to the Board will receive an option to purchase 25,000 shares of the Company’s common stock. Each of these options will vest in equal quarterly installments over a three-year period measured from the date of grant, subject to the director’s continued service as a director, and will become exercisable in full upon a change in control of the Company.

Further, on the date of the first Board meeting held after each annual meeting of stockholders, each non-employee director that has served on the Board for at least six months will receive an option to purchase 10,000 shares of the Company’s common stock. Each of these options will vest in equal quarterly installments over a one-year period measured from the date of grant, subject to the director’s continued service as a director, and will become exercisable in full

(i) on the date that is one business day prior to the date of the Company’s next annual meeting of stockholders (if earlier than the first anniversary of the date of grant) and (ii) upon a change in control of the Company.

The exercise price of all options granted to non-employee directors will equal the closing market price of the Company’s common stock on the date of grant.

The Company will also reimburse non-employee directors for reasonable travel and out-of-pocket expenses incurred in connection with attending Board and committee meetings.