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Exhibit 10.45

SEPRACOR INC.

SUMMARY OF NON-EMPLOYEE DIRECTOR COMPENSATION

        Sepracor Inc. (the "Company") does not pay directors who are also
employees of the Company any additional compensation for their service as a
director. The Company does pay its non-employee directors for their service as
directors.

        As of March 15, 2005, the following represent the compensation program
for each of the Company's non-employee directors:

•an option to purchase 20,000 shares of common stock upon initial election to
the board, such stock option terminating on the earlier to occur of ten years
after the date of grant or 90 days after the optionee ceases to serve as a
director or employee of the Company (or one year in the case of disability or
death) and vesting in equal installments over five years;

•an option to purchase 20,000 shares of common stock annually upon re-election
to the board at the annual meeting of stockholders, such stock option
terminating on the earlier to occur of ten years after the date of grant or
90 days after the optionee ceases to serve as a director or employee of the
Company (or one year in the case of disability or death) and vesting on the
first anniversary of such director's re-election;

•the lead director receives an additional stock option to purchase 2,500 shares
of common stock upon re-election, such stock option having the same terms as the
stock option described in the prior bullet;

•$25,000 per year for service as a director;

•$2,500 for each meeting of the board of directors attended;

•audit committee members, other than the chairman of the committee, receive an
additional $10,000 per year for their service on the committee;

•the chairman of the audit committee receives an additional $12,000 per year for
his service on the committee;

•compensation committee members, other than the chairman of the committee,
receive an additional $5,000 per year for their service on the committee;

•the chairman of the compensation committee receives an additional $6,000 per
year for his service on the committee; and

•expense reimbursement for attending board and committee meetings.

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SEPRACOR INC. SUMMARY OF NON-EMPLOYEE DIRECTOR COMPENSATION