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                                                                   EXHIBIT 10.27


                           EPIX PHARMACEUTICALS, INC.
                DESCRIPTION OF DIRECTOR COMPENSATION ARRANGEMENTS

         The Company pays each non-employee director who serves as a chairman of
a committee of the Board an annual fee of $25,000 for service as a director
of the Company and as a committee chairman. The Company pays each
non-employee director who does not also serve as a chairman of a committee of
the Board an annual fee of $15,000 for service as a director of the Company.
In addition, non-employee directors are eligible to participate in the
Company's Amended and Restated 1996 Director Stock Option Plan (the "Director
Plan"). There are currently 300,000 shares of common stock reserved for
issuance under the Director Plan. Upon the appointment, election or
reelection of a non-employee director, such director is automatically granted
an option to purchase 25,000 shares of common stock. Such options become
exercisable in equal installments over a three year period on each
anniversary of the grant, provided that the optionee is still a director of
the Company at the opening of business on such date. In addition, each
non-employee director is automatically granted an option to purchase 5,000
shares of common stock annually during the years in which such director is
not up for reelection to the Board. Such options become exercisable in full
on the first anniversary date of the grant, provided that the optionee is
still a director of the Company at the opening of business on such date. Each
option has a term of ten years. The exercise price for each option is equal
to the last sale price for the common stock on the business day immediately
preceding the date of grant, as reported on the NASDAQ National Market. The
exercise price may be paid in cash, shares of common stock or a combination
of both. Directors who are also employees of the Company do not receive any
additional compensation for their service on the Board or any committee
thereof.