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                                                                    EXHIBIT 10.8

                                                          GE CAPITAL CORPORATION
                                             LIFE SCIENCE AND TECHNOLOGY FINANCE
                                                         83 WOOSTER HEIGHTS ROAD
                                                               DANBURY, CT 06810
                                                203-205-5216 / FAX: 203-205-2193


                                                                  APRIL 14, 2005

CONFIDENTIAL LOAN PROPOSAL FOR

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COMBINATORX, INCORPORATED

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SUBMITTED BY: Bill Stickle

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COMBINATORX, INCORPORATED
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MR. ROBERT FORRESTER
CHIEF FINANCIAL OFFICER
COMBINATORX, INCORPORATED
650 ALBANY STREET
BOSTON, MA 02118

Dear Mr. Forrester:

Pursuant to your request, General Electric Capital Corporation ("GE Capital") is
pleased to submit the following revised loan proposal for your consideration:

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TRANSACTION:                  LOAN

BORROWER:                     COMBINATORX, INCORPORATED

LENDER:                       GENERAL ELECTRIC CAPITAL CORPORATION ITS
                              AFFILIATES OR ITS ASSIGNEE ("GE CAPITAL")

LOAN AMOUNT:                  $1,000,000.00

ANTICIPATED FUNDING PERIOD:   APRIL 2005 THROUGH MARCH 2006

TERM:                         36 MONTHS

PAYMENT FACTOR AND INTERVAL:  3.215463%, MONTHLY IN ARREARS

INTEREST RATE:                9.76%

EQUIPMENT (COLLATERAL):       NEW LAB AND LAB SUPPORT EQUIPMENT, COMPUTER
                              HARDWARE AND GENERAL OFFICE EQUIPMENT, FURNITURE,
                              AND SOFTWARE AND TENANT IMPROVEMENTS FOR THE
                              INTERNAL USE OF THE BORROWER. SOFT COSTS SUCH AS
                              SOFTWARE AND TENANT IMPROVEMENTS SHALL BE LIMITED
                              TO 30% OF THE LOAN AMOUNT. ALL SUCH EQUIPMENT
                              MUST BE ACCEPTABLE TO GE CAPITAL AND LOCATED
                              WITHIN THE CONTINENTAL UNITED STATES AT BORROWER
                              OWNED OR LEASED PROPERTIES.

WARRANTS:                     BORROWER SHALL ISSUE TO GE CAPITAL PREFERRED
                              STOCK WARRANTS IN THE AMOUNT OF 2.00% OF THE
                              ACTUAL LOAN AMOUNT ADVANCED AT A STRIKE PRICE
                              EQUAL TO THE MOST RECENT ROUND'S PREFERRED SHARE
                              PRICE.

OTHER CONSIDERATION:          BORROWER SHALL PROVIDE LENDER WITH A NEGATIVE
                              PLEDGE ON INTELLECTUAL PROPERTY. LENDER
                              ACKNOWLEDGES THE EXISTENCE OF A NEGATIVE PLEDGE
                              BETWEEN BORROWER AND LIGHTHOUSE CAPITAL PARTNERS
                              ("LIGHTHOUSE"). LENDER INTENDS TO ALLOW ITS
                              NEGATIVE PLEDGE WITH BORROWER TO MIRROR THE
                              NEGATIVE PLEDGE THAT BORROWER HAS WITH
                              LIGHTHOUSE.
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                          GENERAL TERMS AND CONDITIONS

OUR PROPOSAL CONTAINS THE FOLLOWING PROVISIONS AND THE LOAN PAYMENTS WE PROPOSE
ARE SPECIFICALLY BASED UPON THESE PROVISIONS AND OUR ASSUMPTIONS.

1.   MAINTENANCE AND INSURANCE: All maintenance and insurance (fire and theft,
     extended coverage and liability) are the responsibility of the Borrower.
     Borrower will be responsible for maintaining in force, all risk damage, and
     liability insurance in amounts and coverages satisfactory to GE Capital.

2.   DOCUMENTATION: GE Capital's current standard loan documentation for this
     type of collateralized loan will be used.


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3.   INDEXING: The Interest Rate and Payment Factor will be adjusted at the time
     of funding to reflect any increase in the Lender's cost of funds, which
     shall be tied to the Federal Reserve's Three (3) year Treasury Constant
     Maturities Rate. The rate, and therefore the payment factor, assumes an
     index of 3.91%.

4.   TRANSACTION COSTS: The Borrower shall be responsible for all closing and
     transaction costs including any legal fees and inspection and/or appraisal
     costs.

5.   PROPOSAL FEE: $10,000.00. Of this Fee, $5,000.00 shall be credited on a
     prorata basis to schedules as financed and the remainder retained by GE
     Capital for application processing, underwriting and documentation. All or
     a portion of the proposal fee will be forfeited if this transaction is
     approved by GE Capital and not executed by Borrower as called for in this
     proposal. If investment approval is not obtained, the fee will be promptly
     returned to Borrower (less the cost of credit verification and
     investigation and any out of pocket expenses incurred such as appraisal
     fees, legal fees, etc.).

6.   ACCEPTANCE: By signing below, the Borrower acknowledges the terms and
     conditions of this proposal. Upon receipt of the executed proposal letter
     and accompanying fee, GE Capital shall commence its investment approval
     process.

7.   EXPIRATION: This proposal shall expire on May 3, 2005, if GE Capital has
     not received your acceptance hereof by such date.

This proposal expresses GE Capital's willingness to seek internal approval for
the transaction contemplated herein. By signing and returning this letter both
parties acknowledge that: The above proposed terms and conditions do not
constitute a commitment by GE Capital, (ii) GE Capital's senior management may
seek changes to the above terms and conditions, and (iii) GE Capital may decline
further consideration of this transaction at any point in the approval process.
GE Capital's agreement to fund the proposed transaction remains subject to and
would be preceded by completion of a legal and business due diligence, as well
as collateral and credit review and analysis, all with results satisfactory to
GE Capital and the closing of an initial funding under such transaction would be
conditioned upon the prior execution and delivery of final legal documentation
and all conditions precedent acceptable to GE Capital and its counsel and no
material adverse change in the business condition or prospects of the Company
("Material Adverse Change"). For transactions that contemplate more than one
funding, GE Capital's obligation to make each such subsequent funding would be
subject to confirmation that no Material Adverse Change has occurred.

I look forward to your early review and response. If there are any questions, I
would appreciate the opportunity to discuss this proposal in more detail at your
earliest convenience. Please do not hesitate to contact me directly at
(203) -205 -5216.

Sincerely,


PROPOSAL ACCEPTED BY:

COMBINATORX, INCORPORATED

Name:   /s/ Robert Forrester
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Title: Chief Financial Officer
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Date:  May 3, 2005
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Federal Tax ID#:


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