EXHIBIT 10.48 EXECUTIVE OFFICER COMPENSATION SUMMARY

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                                                                   EXHIBIT 10.48

                     EXECUTIVE OFFICER COMPENSATION SUMMARY

     Momenta Pharmaceuticals, Inc.'s (the "Company") executive officers consist

of: (i) Alan L. Crane, Chairman, President and Chief Executive Officer; (ii)

John Bishop, Vice President, Pharmaceutical Sciences and Manufacturing; (iii)

Steven B. Brugger, Vice President, Strategic Product Development; (iv) Richard

P. Shea, Vice President, Chief Financial Officer; (v) Ganesh Venkataraman, Vice

President, Technology; and (vii) Susan K. Whoriskey, Vice President, Licensing

and Business Development.

     The compensation structure for executive officers of the Company consists

of three components: base salary, a discretionary annual cash bonus and stock

options.

EMPLOYMENT AGREEMENTS WITH EXECUTIVE OFFICERS

     The Company has entered into employment agreements with Alan L. Crane,

Ganesh Venkataraman and Susan K. Whoriskey. The annual salary, severance and

termination provisions of such agreements are as follows:

     ALAN L. CRANE

     The Company entered into an employment agreement with Mr. Crane, dated

March 15, 2002. Pursuant to this agreement, Mr. Crane is to receive an annual

base salary of $370,000, subject to annual increases upon review by the

Compensation Committee of the Board of Directors (the "Committee"). In

connection with the execution of the agreement, the Company paid Mr. Crane a

bonus of $106,585 on March 15, 2002.

     Under Mr. Crane's agreement, either the Company or Mr. Crane may terminate

his employment at any time, subject to continuation of salary payment and

benefits for one year if the Company terminates Mr. Crane's employment without

cause or Mr. Crane terminates his employment for good r