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                                                                   EXHIBIT 10.32

                          TRUBION PHARMACEUTICALS, INC.

                       RESTRICTED STOCK PURCHASE AGREEMENT

     This Restricted Stock Purchase Agreement (the "AGREEMENT") is made as of
January 28th, 2004 by and between Trubion Pharmaceuticals, Inc., a Delaware
corporation (the "COMPANY"), and Lee Brettman, MD, FACP (the "PURCHASER").

     In consideration of the mutual covenants and representations set forth
below, the Company and Purchaser agree as follows:

     1. Purchase and Sale of the Shares. Subject to the terms and conditions of
this Agreement, the Company agrees to sell to Purchaser and Purchaser agrees to
purchase from the Company at the Closing (as defined below) 100,000 shares of
the Company's Common Stock (the "SHARES") at a price of $0.05 per share (the
"PURCHASE PRICE"), for an aggregate purchase price of $5,000.

     2. Closing. The purchase and sale of the Shares shall occur at a closing
(the "CLOSING") to be held on the date first set forth above, or at any other
time mutually agreed upon by the Company and Purchaser. The Closing will take
place at the principal office of the Company or at such other place as shall be
designated by the Company. At the Closing, Purchaser shall deliver the aggregate
Purchase Price set forth above to the Company by check payable to the Company,
and the Company will issue, as promptly thereafter as practicable, a stock
certificate, registered in the name of the Purchaser, reflecting the Shares.

     3. Repurchase Option.

          A. In the event the Purchaser ceases to be an employee, consultant or
director (a "SERVICE PROVIDER") for any or no reason, including without
limitation, by reason of Purchaser's death or disability (as defined in Section
22(e)(3) of the Internal Revenue Code of 1986, as amended (the "CODE"),
"DISABILITY") resignation or involuntary termination, the Company shall upon the
date of such termination (as reasonably fixed and determined by the Company)
have the right, but not the obligation (the "REPURCHASE OPTION"), for a period
of ninety (90) days from such date, to repurchase any Shares which have not yet
been released from the Repurchase Option (the "UNRELEASED SHARES") at a price
per share equal to the lesser of (x) the fair market value of the shares at the
time the Repurchase Option is exercised, as determined by the Company's board of
directors and (y) the Purchase Price (the "REPURCHASE PRICE"). The Repurchase
Option shall be exercised by the Company (i) by delivering written notice to the
Purchaser or, in the event of the, Purchaser or the Purchaser's executor a check
in the amount of the aggregate Repurchase Price, or (ii) by canceling an amount
of the Purchaser's indebtedness to the Company equal to the aggregate Repurchase
Price, or (iii) by a combination of (i) and (ii) so that the combined payment
and cancellation of indebtedness equals the aggregate Repurchase Price. Upon
delivery of such notice and the payment of the aggregate Repurchase Price, the
Company shall become the legal and beneficial owner of the Unreleased Shares
being repurchased and all rights and interests therein or relating thereto and
the Company shall have the right to retain and transfer to its own name the
number of Unreleased Shares being repurchased by the Company.

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          B. The Company in its sole discretion may designate and assign one or
more employees, officers, directors or stockholders of the Company or other
persons or organizations to exercise all or a part of the Company's Repurchase
Option to purchase all or a part of the Unreleased Snares.

     4. Release of Shares From Repurchase Option; Vesting.

          A. So long as the Purchaser's continuous status as a Service Provider
has not yet terminated in each such instance, 25% of the total number of Shares
shall be released from the Repurchase Option on the date of this Agreement, and
an additional 1/36th of the remaining Shares shall be released from the
Repurchase Option on the corresponding day of each month thereafter, or on the
last day of each month, to the extent each month thereafter does not have the
corresponding day, until all Shares have been released on the third anniversary
of this Agreement.

     5. Restrictions on Transfer.

          A. The Purchaser hereby makes the investment representations listed on
EXHIBIT A to the Company as of the date of this Agreement and as of the date of
the Closing, and agrees that such representations are incorporated into this
Agreement by this reference, such that the Company may rely on them in issuing
the Shares. Purchaser understands and agrees that the Company shall cause the
legends set forth below, or substantially equivalent legends, to be placed upon
any certificate(s) evidencing ownership of the Shares, together with any other
legends that may be required by the Company or by applicable state or federal
securities laws:

          THE SECURITIES REPRESENTED HEREBY HAVE NOT BEEN REGISTERED UNDER THE
          SECURITIES ACT OF 1933 (THE "ACT") AND MAY NOT BE OFFERED, SOLD OR
          OTHERWISE TRANSFERRED, PLEDGED OR HYPOTHECATED UNLESS AND UNTIL
          REGISTERED UNDER THE ACT OR, IN THE OPINION OF COUNSEL SATISFACTORY TO
          THE ISSUER OF THESE SECURITIES, SUCH OFFER, SALE OR TRANSFER, PLEDGE
          OR HYPOTHECATION OTHERWISE COMPLIES WITH THE ACT.

          THE SHARES REPRESENTED BY THIS CERTIFICATE ARE SUBJECT TO CERTAIN
          RESTRICTIONS ON TRANSFER, A RIGHT OF FIRST REFUSAL, AND A REPURCHASE
          OPTION HELD BY THE ISSUER OR ITS ASSIGNEE(S) AS SET FORTH IN THE
          RESTRICTED STOCK PURCHASE AGREEMENT BETWEEN THE ISSUER AND THE
          ORIGINAL HOLDER OF THESE SHARES, A COPY OF WHICH MAY BE OBTAINED AT
          THE PRINCIPAL OFFICE OF THE ISSUER. SUCH TRANSFER RESTRICTIONS, RIGHT
          OF FIRST REFUSAL AND REPURCHASE OPTION ARE BINDING ON TRANSFEREES OF
          THESE SHARES.

          B. Stop-Transfer Notices. Purchaser agrees that to ensure compliance
with the restrictions referred to herein, the Company may issue appropriate
"stop transfer" instructions to its


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transfer agent, if any, and that, if the Company transfers its own securities,
it may make appropriate notations, to the same effect in its own records.

          C. Refusal to Transfer. The Company shall not be required (i) to
transfer on its books any Shares that have been sold or otherwise transferred ha
violation of any of the provisions of this Agreement or (ii) to treat as owner
of such Shares or to accord the right to vote or pay dividends to any purchaser
or other transferee to whom such Shares shall have been so transferred.

          D. Lock-Up Period. Purchaser hereby agrees that Purchaser shall not
sell, offer, pledge, contract to sell, grant any option or contract to purchase,
purchase any option or contract to sell, grant any right or warrant to purchase,
lend or otherwise transfer or encumber, directly or indirectly, any Shares or
other securities of the Company, nor shall Purchaser enter into any swap,
hedging or other arrangement that transfers to another, in whole or in part, any
of the economic consequences of ownership of any Shares or other securities of
the Company, during the 180-day period (or such other shorter period as may be
requested in writing by the managing underwriter and agreed to in writing by the
Company) following the effective date of the first registration statement of the
Company filed under the Securities Act of 1933, as amended, that includes
securities to be sold on behalf of the Company to the public in an underwritten
public offering under such Securities Act. Purchaser further agrees, if so
requested by the Company or any representative of its underwriters, to enter
into such underwriter's standard form of "lock-up" or "market standoff"
agreement in a form satisfactory to the Company and such underwriter. The
Company may impose stop-transfer instructions with respect to securities subject
to the foregoing restrictions until the end of such period.

          E. Unreleased Shares. Notwithstanding anything to the contrary in this
Agreement (including Section 6 hereof), Unreleased Shares subject to the
Repurchase Option contained in Sections of this Agreement, nor any beneficial
interest in such Shares, shall be sold, gifted, transferred, encumbered or
otherwise disposed of in any way (whether by operation of law or otherwise) by
the Purchaser.

          F. Released Shares. No Shares purchased pursuant to this Agreement,
nor any beneficial interest in such Shares, shall be sold, transferred,
encumbered or otherwise disposed of in any way (whether by operation of law or
otherwise) by the Purchaser or any subsequent transferee, other man in
compliance with the Company' s right of first refusal provisions contained in
Section 6 of this Agreement.

     6. Company's Right of First Refusal. Subject to Section 5E hereof, before
any Shares acquired by the Purchaser pursuant to this Agreement (or any
beneficial interest in such Shares) may be sold, transferred, encumbered or
otherwise disposed of in any way (whether by operation of law or otherwise) by
the Purchaser or any subsequent transferee (each a "HOLDER"), such Holder must
first offer such Shares or beneficial interest to the Company and/or its
assignee(s) as follows:

          A. Notice of Proposed Transfer. The Holder shall deliver to the
Company a written notice stating: (i) the Holder's bona fide intention to sell
or otherwise transfer the Shares; (ii) the name of each proposed transferee;
(iii) the number of Shares to be transferred to each proposed transferee; (iv)
the bona fide cash price or other consideration for which the Holder


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proposes to transfer the Shares; and (v) that by delivering the notice, the
Holder offers all such Shares to the Company and/or its assignee(s) pursuant to
this Section and on the same terms described in the notice.

          B. Exercise of Right of First Refusal. At any time within 30 days
after receipt of the Holder's notice, the Company and/or its assignee(s) may, by
giving written notice to the Holder, elect to purchase all, but not less than
all, of the Shares proposed to be transferred to any one or more of the proposed
transferees, at the purchase price determined in accordance with Section 6C.

          C. Purchase Price. The purchase price for the Shares purchased by the
Company and/or its assignee(s) under this Section shall be the price listed in
the Holder's notice. If the price listed in the Holder's notice includes
consideration other than cash, the cash equivalent value of the non-cash
consideration shall be determined by the Board of Directors of the Company in
its sole discretion.

          D. Payment. Payment of the purchase price shall be made, at the option
of the Company and/or its assignee(s), in cash (by check), by cancellation of
all or a portion of any outstanding indebtedness of the Holder to the Company
and/or its assignee(s), or by any combination thereof within 30 days after
receipt by the Company of the Holder's notice (or at such later date as is
called for by such notice).

          E. Holder's Right to Transfer. If all of the Shares proposed in the
notice to be transferred to a given proposed transferee are not purchased by the
Company and/or its assignee(s) as provided in this Section, then the Holder may
sell or otherwise transfer such Shares to that proposed transferee, provided
that: (i) the transfer is made only on the terms provided for in the notice,
with the exception of the purchase price, which may be either the price listed
in the notice or any higher price; (ii) such transfer is consummated within 60
days after the date the notice is delivered to the Company; (iii) the transfer
is effected in accordance with any applicable securities laws, and if requested
by the Company, the Holder shall have delivered an opinion of counsel acceptable
to the Company to that effect; and (iv) the proposed transferee agrees in
writing that the provisions of this Section shall continue to apply to the
..transferred Shares in the hands of such proposed transferee. If any Shares
described in a notice are not transferred to the proposed transferee within the
period provided above, then before any such Shares may be transferred, a new
notice shall be given to the Company, and the Company and/or its assignees shall
again be offered the right of first refusal described in this Section.

          F. Exception for Certain Family Transfers. Notwithstanding anything to
the contrary contained elsewhere in this Section, the transfer of any or all of
the Shares during the Holder's lifetime or on the Holder's death by will or
intestacy to the Holder's spouse, child, father, mother, brother, sister,
father-in-law, mother-in-law, brother-in-law, sister-in-law, grandfather,
grandmother, grandchild, cousin, aunt, uncle, niece, nephew, stepchild, or to a
trust or other similar estate planning vehicle for the benefit of the Holder or
any such person, shall be exempt from the provisions of this Section; provided
that, in each such case, the transferee shall agree in writing to receive and
hold the Shares so transferred subject to all of the provisions of this
Agreement, including but not limited to this Section, and there shall be no
further transfer of such Shares except in accordance with, the terms of this
Section.


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          G. Termination of Right of First Refusal. The right of first refusal
contained in this Section shall terminate as to all Shares purchased hereunder
upon the earlier of: (i) the closing date of the first sale of Common Stock of
the Company to the general public pursuant to a registration statement filed
with and declared effective by the Securities and Exchange Commission under the
Securities Act, as amended, and (ii) the closing date of a Change of Control
pursuant to which the holders of the outstanding voting securities of the
Company receive securities of a class registered pursuant to Section 12 of the
Securities Exchange Act of 1934, as amended. For purposes of this Agreement, a
"CHANGE OF CONTROL" means either:

               (1) the acquisition of the Company by another entity by means of
any transaction or series of related transactions (including, without
limitation, any reorganization, merger or consolidation or stock transfer, but
excluding any such transaction effected primarily for the purpose of changing
the domicile of the Company), unless the Company's stockholders of record
immediately prior to such transaction or series of related transactions hold,
immediately after such transaction or series of related transactions, at least
50% of the voting power of the surviving or acquiring entity (provided that the
sale by the Company of its securities for the purposes of raising additional
funds shall not constitute a Change of Control hereunder); or

               (2) a sale of all or substantially all of the assets of the
Company.

     7. Escrow.

          A. As security for the faithful performance of this Agreement,
Purchaser agrees, immediately upon receipt of the certificate(s) evidencing the
Shares, to deliver such certificate(s), together with a stock power in the form
of EXHIBIT B attached to this Agreement, executed by Purchaser (with the date
and number of Shares left blank), to the Secretary of the Company or its
designee (the "ESCROW AGENT"). These documents shall be held by the Escrow Agent
pursuant to the Joint Escrow Instructions of the Company and Purchaser set forth
in EXHIBIT C attached to this Agreement, which instructions are incorporated
into this Agreement by this reference, and which instructions shall also be
delivered to the Escrow Agent after the Closing Date.

          B. Subject to the terms hereof, the Purchaser shall have all the
rights of a stockholder with respect to such Shares while they are held in
escrow, including without limitation, the right to vote the Shares. If, from
time to time during the term of the Company's Repurchase Option, there is (i)
any stock dividend, stock split or other change in the Shares, (ii) any dividend
of cash or other property on the Shares, or (iii) any merger or sale of all or
substantially all of the assets or other acquisition of the Company, any and all
new, substituted or additional securities or cash or other consideration to
which the Purchaser is entitled by reason of the Purchaser's ownership of the
Shares shall immediately become subject to this escrow, deposited with the
Escrow Agent and included thereafter as "SHARES" for purposes of this Agreement
and the Company's Repurchase Option.

     8. Tax Consequences. The Purchaser has reviewed with the Purchaser's own
tax advisors the federal, state, local and foreign tax consequences of this
investment and the transactions contemplated by this Agreement. The Purchaser is
relying solely on such advisors and not on any statements or representations of
the Company or any of its agents. The Purchaser understands that


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<PAGE>

the Purchaser (and not the Company) shall be responsible for any tax liability
that may arise as a result of the transactions contemplated by this Agreement.
The Purchaser understands that Section 83 of the Code, taxes as ordinary income
the difference between the purchase price for the Shares and the Fair Market
Value of the Shares as of the date any restrictions on the Shares lapse. In this
context, "restriction" includes the right of the Company to buy back the Shares
pursuant to the Repurchase Option. The Purchaser understands that the Purchaser
may elect to be taxed at the time the shares are purchased rather than when and
as the Repurchase Option expires by filing an election under Section 83(b) of
the Code with the IRS within 30 days from the date of purchase. THE FORM FOR
MAKING THIS SECTION 83(B) ELECTION IS ATTACHED TO THIS AGREEMENT AS EXHIBIT D
AND THE PURCHASER (AND NOT THE COMPANY OR ANY OF ITS AGENTS) SHALL BE SOLELY
RESPONSIBLE FOR APPROPRIATELY FILING SUCH FORM, EVEN IF THE PURCHASER REQUESTS
THE COMPANY OR ITS AGENTS TO MAKE THIS FILING ON PURCHASER'S BEHALF.

     9. General Provisions.

          A. Choice of Law; Entire Agreement. This Agreement shall be governed
by the internal substantive laws, but not the choice of law rules, of
Washington.

          B. Integration. This Agreement represents the entire agreement between
the parties with respect to the purchase of the Shares by the Purchaser and
supercedes and replaces any and all prior written or oral agreements regarding
the subject matter of this Agreement including, but not limited to, any
representations made during any interviews, relocation discussions or
negotiations whether written or oral.

          C. Notices. Any notice, demand, offer, request or other communication
required or permitted to be given by either the Company or the Purchaser
pursuant to the terms of this Agreement shall be in writing and shall be deemed
effectively given the earlier of (i) when received, (ii) when delivered
personally, (iii) one business day after being delivered by facsimile (with
receipt of appropriate confirmation), (iv) one business day after being
deposited with an overnight courier service or (v) four days after being
deposited in the U.S. mail, First Class with postage prepaid, and addressed to
the parties at the addresses provided to the company (which the Company agrees
to disclose to the other parties upon request) or such other address as a party
may request by notifying the other in writing.

          D. Successors. Any successor to the Company (whether direct or
indirect and whether by purchase, merger, consolidation, liquidation or
otherwise) to all or substantially all of the Company's business and/or assets
shall assume the obligations under this Agreement and agree expressly to perform
the obligations under this Agreement in the same manner and to the same extent
as the Company would be required to perform such obligations in the absence of a
succession. For all purposes under this Agreement, the term "Company" shall
include any successor to the Company's business and/or assets which executes and
delivers the assumption agreement described in this Section or which becomes
bound by the terms of this Agreement by operation of law. Subject to the
restrictions on transfer set forth in this Agreement, this Agreement shall be
binding upon Purchaser and his heirs, executors, administrators, successors and
assigns.


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          E. Assignment. The rights granted to the Purchaser under this
Agreement are not assignable by the Purchaser under any circumstances.

          F. Waiver. Either party's failure to enforce any provision of this
Agreement shall not in any way be construed as a waiver of any such provision,
nor prevent that party from thereafter enforcing any other provision of this
Agreement. The rights granted both parties hereunder are cumulative and shall
not constitute a waiver of either party's right to assert any other legal remedy
available to it.

          G. Purchaser Investment Representations and Further Documents. The
Purchaser agrees upon request to execute any further documents or instruments
necessary or reasonably desirable in the view of the Company to carry out the
purposes or intent of this Agreement, including (but not limited to) EXHIBITS A,
B, C AND D of this Agreement.

          H. Severability. Should any provision of this Agreement be found to be
illegal or unenforceable, the other provisions shall nevertheless remain
effective and shall remain enforceable to the greatest extent permitted by law.

          I. Rights as Stockholder. Subject to the terms and conditions of this
Agreement, Purchaser shall have all of the rights of a stockholder of the
Company with respect to the Shares from and after the date that Purchaser
delivers a fully executed copy of this Agreement (including all exhibits and
attachments thereto) and full payment for the Shares to the Company, and until
such time as Purchaser disposes of the Shares in accordance with this Agreement.
Upon such transfer, Purchaser shall have no further rights as a holder of the
Shares so purchased except (in the case of a transfer to the Company) the right
to receive payment for the Shares so purchased in accordance with the provisions
of this Agreement, and Purchaser shall forthwith cause the certificate(s)
evidencing the Shares so purchased to be surrendered to the Company for transfer
or cancellation.

          J. Adjustment for Stock Split. All references to the number of Shares
and the purchase price of the Shares in this Agreement shall be adjusted to
reflect any stock split, stock dividend or other change in the Shares which may
be made after the date of this Agreement.

          K. Employment at Will. PURCHASER ACKNOWLEDGES AND AGREES THAT THE
VESTING OF SHARES PURSUANT TO THIS AGREEMENT IS EARNED ONLY BY CONTINUING
SERVICE AS A SERVICE PROVIDER AT WILL (AND NOT THROUGH THE ACT OP BEING HIRED OR
PURCHASING SHARES HEREUNDER). PURCHASER FURTHER ACKNOWLEDGES AND AGREES THAT
THIS AGREEMENT, THE TRANSACTIONS CONTEMPLATED HEREUNDER AND THE VESTING SCHEDULE
SET FORTH HEREIN DO NOT CONSTITUTE AN EXPRESS OR IMPLIED PROMISE OF CONTINUED
ENGAGEMENT AS A SERVICE PROVIDER FOR THE VESTING PERIOD, OR FOR ANY PERIOD AT
ALL, AND SHALL NOT INTERFERE WITH PURCHASER'S RIGHT OR THE COMPANY'S RIGHT TO
TERMINATE PURCHASER'S RELATIONSHIP WITH THE COMPANY AT ANY TIME, WITH OR WITHOUT
CAUSE OR NOTICE.

          L. Arbitration. Any and all controversies, claims, or disputes arising
out of, relating to, or resulting from this Agreement shall be subject to
binding arbitration under the


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Arbitration Rules set forth in the Washington Code of Civil Procedure Chapter
7.04 (the "RULES") of the Revised Code of Washington and pursuant to Washington
law. Any arbitration will be administered by the American Arbitration
Association ("AAA") in accordance with its Rules for the Resolution of
Commercial Disputes. Purchaser agrees that the arbitrator shall have the power
to decide any motions brought by any party to the arbitration, including motions
for summary judgment and/or adjudication and motions to dismiss and demurrers,
prior to any arbitration hearing. Purchaser also agrees that the arbitrator
shall have the power to award any remedies, including attorneys' fees and costs
available under applicable law. Purchaser understands that each party shall bear
its own costs and expenses, including attorneys' fees incurred in connection in
connection with any arbitration. The decision of the arbitrator shall be in
writing. Except as provided by the Rules, arbitration shall be the sole,
exclusive and final remedy for any dispute under this Agreement. Accordingly,
except as provided for by the Rules, neither the Purchaser nor the Company will
be permitted to pursue court action regarding this Agreement. In addition to the
right under the Rules to petition the court for provisional relief, the
Purchaser agrees that any party may also petition the court for injunctive
relief where either party alleges or claims a violation of any confidential
information or invention assignment agreement between the Purchaser and the
Company or any other agreement regarding trade secrets, confidential information
or nonsolicitation. In the event either party seeks injunctive relief, the
prevailing party shall be entitled to recover reasonable costs and attorneys'
fees.

          M. Counterparts. This Agreement may be executed in one or more
counterparts, each of which will be deemed an original, but all of which
together will constitute one and the same agreement. Facsimile copies of signed
signature pages shall be binding originals.


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<PAGE>

     The parties represent that they have read this Agreement in its entirety,
have had an opportunity to obtain the advice of counsel prior to executing this
Agreement and fully understand this Agreement. The Purchaser agrees to notify
the Company of any change in his address below.

PURCHASER                               TRUBION PHARMACEUTICALS, INC.


/s/ Lee Brettman                        /s/ Peter A. Thompson
-------------------------------------   ----------------------------------------
Signature                               Signature

Lee Brettman                            Peter A. Thompson
Print Name                              Print Name

                                        President & CEO
                                        Print Title

Address:

-------------------------------------

-------------------------------------

<PAGE>

                                    Exhibit A

                       INVESTMENT REPRESENTATION STATEMENT

PURCHASER : Lee Brettman, MD, FACP

COMPANY   : Trubion Pharmaceuticals, Inc.

SECURITY  : Common Stock

AMOUNT    : 100,000 shares

DATE      : January __, 2004

     In connection with the purchase of the above-listed shares, I, the
undersigned purchaser, represent to the Company as follows:

     1. The Company may Rely on These Representations. I understand that the
Company's sale of the shares to me has not been registered under the Securities
Act of 1933, as amended, because the Company believes, relying in part on my
representations in this document, that an exemption from such registration
requirement is available for such sale. I understand that the availability of
this exemption depends upon the representations I am making to the Company in
this document being true and correct.

     2. I am Purchasing for Investment. I am purchasing the shares solely for
investment purposes, and not for further distribution. My entire legal and
beneficial ownership interest in the shares is being purchased and shall be held
solely for my account, except to the extent I intend to hold the shares jointly
with my spouse. I am not a party to, and do not presently intend to enter into,
any contract or other arrangement with any other person or entity involving the
resale, transfer, grant of participation with respect to or other distribution
of any of the shares. My investment intent is not limited to my present
intention to hold the shares for the minimum capital gains period specified
under any applicable tax law, for a deferred sale, for a specified increase or
decrease in the market price of the shares, or for any other fixed period in the
future.

     3. I Can Protect My Own Interests. I can properly evaluate the merits and
risks of an investment in the shares and can protect my own interests in this
regard, whether by reason of my own business and financial expertise, the
business and financial expertise of certain professional advisors unaffiliated
with the Company with whom I have consulted, or my preexisting business or
personal relationship with the Company or any of its officers, doctors or
controlling persons.

     4. I am Informed About the Company. I am sufficiently aware of the
Company's business affairs and financial condition to reach an informed and
knowledgeable decision to acquire the shares. I have had opportunity to discuss
the plans, operations and financial condition of the

<PAGE>

Company with its officers, directors or controlling persons, and have received
all information I deem appropriate for assessing the risk of an investment in
the shares.

     5. I Recognize My Economic Risk. I realize that the purchase of the shares
involves a high degree of risk, and that the Company's future prospects are
uncertain. I am able to hold the shares indefinitely if required, and am able to
hear the loss of my entire investment in the shares.

     6. I Know the Shares are Restricted Securities. I understand that the
shares are "restricted securities" in that the Company's sale of the shares to
me has not been registered under the 'Securities Act in reliance upon an
exemption for non-public offerings. In this regard, I also understand and agree
that:

          A. I must hold the shares indefinitely, unless any subsequent proposed
resale by me is registered under the Securities Act, or unless an exemption from
registration is otherwise available (such as Rule 144);

          B. the Company is under no obligation to register any subsequent
proposed resale of the shares by me; and

          C. the certificate evidencing the shares will be imprinted with a
legend which prohibits the transfer of the shares unless such transfer is
registered or such registration is not required in the opinion of counsel for
the Company.

     7. I am Familiar With Rule 144. I am familiar with Rule 144 adopted under,
the Securities Act, which in some circumstances permits limited public resales
of "restricted securities" like the shares acquired from an issuer in a
non-public offering. I understand that my ability to sell the shares under Rule
144 in the future is uncertain, and will depend upon, among other things: (i)
the availability of certain current public information about the Company; (ii)
the resale occurring more than one year after my purchase and full payment
(within the meaning of Rule 144) for the shares; and (iii) if I am an affiliate
of the Company, or a non-affiliate who has held the shares less than two years
after my purchase and full payment: (A) the sale being made through a broker in
an unsolicited "broker's transaction" or in transactions directly with a market
maker, as said term is defined under the Securities Exchange Act of 1934, as
amended, (B) the amount of shares being sold during any three month period not
exceeding the specified limitations stated in Rule 144, and (C) timely filing of
a notice of proposed sale on Form 144, if applicable.

     8. I Know Rule 144 May Never be Available. I understand that the
requirements of Rule 144 may never be met, and that the shares may never be
saleable. I further understand that at the time I wish to sell the shares, there
may be no public market for the Company's stock upon which to make such a sale,
or the current public information requirements of Rule 144 may not be satisfied,
either of which would preclude me from selling the shares under Rule 144 even if
the one-year minimum holding period had been satisfied.

     9. I Know I am Subject to Further Restrictions on Resale. I understand that
in the event Rule 144 is not available to me, any future proposed sale of any of
the shares by me will not be possible without prior registration under the
Securities Act, compliance with some other registration


                                      -2-

<PAGE>

exemption (which may or may not be available), or each of the following: (i) my
written notice to the Company containing detailed information regarding the
proposed sale, (ii) my providing an opinion of my counsel to the effect that
such sale will not require registration, and (iii) the Company notifying me in
writing that its counsel concurs in such opinion. I understand that neither the
company nor its counsel is obligated to provide me with any such opinion. I
understand that although Rule 144 is not exclusive, the Staff of the SEC has
stated that persons proposing to sell private placement securities other than in
a registered offering or pursuant to Rule 144 will have a substantial burden of
proof in establishing that an exemption from registration is available for such
offers or sales and that such persons and their respective brokers who
participate in such transactions do so at their own risk.

     10. I Know I May Have Tax Liability Due to the Uncertain Value of the
Shares. I understand that the Board of Directors believes its valuation of the
shares represents a fair appraisal of their worth, but that it remains possible
that, with the benefit of hindsight, the Internal Revenue Service may
successfully assert that the value of the shares on the date of my purchase is
substantially greater than the Board's appraisal. I understand that any
additional value ascribed to the shares by such an IRS determination will
constitute ordinary income to me as of the purchase date, and that any
additional taxes and interest due as a result will be my sole responsibility
payable only by me, and that the Company need not and will not reimburse me for
that tax liability. I understand that if such additional value represents more
than 25% of my gross income for the year in which the value of the shares is
taxable, the IRS will have 6 years from the due date for filing the return (or
the actual filing date of the return if filed thereafter) within which to assess
me the additional tax and interest due.

     11. Residence. The address of my principal residence is set forth on the
signature page below.

     By signing below, I acknowledge my agreement with each of the statements
contained in this Investment Representation Statement as of the date first set
forth above, and my intent for the Company to rely on such statements in issuing
the shares to me.


                                        ----------------------------------------
                                        Purchaser's Signature

                                        Lee Brettman, MD, FACP
                                        Print Name

Address of Purchaser's
Principal Residence:

-------------------------------------

-------------------------------------


                                      -3-

<PAGE>

                                    EXHIBIT C

                            JOINT ESCROW INSTRUCTIONS

Trubion Pharmaceuticals, Inc.
2401 4th Avenue, Suite 1050
Seattle, Washington 98121
Attn: Mr. Hans van Houte

Dear Mr. van Houte:

     As Escrow Agent for both Trubion Pharmaceuticals, Inc., a Delaware,
corporation (the "COMPANY"), and Lee Brettman, MD3 FACP ("PURCHASER"), you are
hereby authorized and directed to hold the documents delivered to you pursuant
to the terms of that certain Restricted Stock Purchase Agreement (the
"AGREEMENT"), dated as of January ______, 2004, to which a copy of these Joint
Escrow Instructions is attached, in accordance with the following instructions:

     1. In the event that the Company and/or any assignee of the Company
(referred to collectively for convenience herein as the "COMPANY") exercises the
Repurchase Option set forth in the Agreement, the Company shall give to
Purchaser and you a written notice specifying the number of shares of stock to
be purchased, the purchase price, and the time for a closing hereunder at the
principal office of the Company. Purchaser and the Company hereby irrevocably
authorize and direct you to close the transaction contemplated by such notice in
accordance with the terms of said notice.

     2. At the closing, you are directed (a) to date the stock assignments
necessary for the transfer in question, (b) to fill in the number of shares
being transferred, and (c) to deliver same, together with the certificate
evidencing the shares of stock to be transferred, to the Company against the
simultaneous delivery to you of the purchase price (by check or such other form
of consideration mutually agreed to by the parties) for the number of shares of
stock being purchased pursuant to the exercise of the Repurchase Option.

     3. Purchaser irrevocably authorizes the Company to deposit with you any
Certificates evidencing shares of stock to be held by you hereunder and any
additions and substitutions to said shares as defined in the Agreement.
Purchaser does hereby irrevocably constitute and appoint you as his
attorney-in-fact and agent for the term of this escrow to execute with respect
to such securities all documents necessary or appropriate to make such
securities negotiable and to complete any transaction herein contemplated.
Subject to the provisions of this paragraph 3, Purchaser shall exercise all
rights and privileges of a stockholder of the Company while the stock is held by
you.

     4. Upon written request of Purchaser after each successive 1-year period
from the date of the Agreement, unless the Repurchase Option has been exercised,
you will deliver to Purchaser a certificate or certificates representing so many
shares as are not then subject to the Repurchase Option. On the date that is 95
days after the date the Purchaser's status as a service provider (as defined in
the Agreement) to the Company terminates, you will deliver to Purchaser a
certificate or certificates representing the aggregate number of shares sold and
issued pursuant to the Agreement

<PAGE>

and not purchased by the Company or its assignees pursuant to the exercise of
the Repurchase Option.

     5. If at the time of termination of this escrow you should have in your
possession any documents, securities, or other property belonging to Purchaser,
you shall deliver all of same to Purchaser and shall be discharged of all
further obligations hereunder.

     6. Your duties hereunder may be altered, amended, modified or revoked only
by a writing signed by all of the parties hereto.

     7. You shall be obligated only for the performance of such duties as are
specifically set forth herein and may rely and shall be protected in relying or
refraining from acting on any instrument reasonably believed by you to be
genuine and to have been signed or presented by the proper party or parties. You
shall not be personally liable for any act you may do or omit to do hereunder as
Escrow Agent or as attorney-in-fact for Purchaser while acting in good faith and
in the exercise of your own good judgment, and any act done or omitted by you
pursuant to the advice of your own attorneys shall be conclusive evidence of
such good faith.

     8. The Company and the Purchaser hereby jointly and severally expressly
agree to indemnify and hold harmless you and your designees against any and all
claims, losses, liabilities, damages, deficiencies, costs and expenses,
including reasonable attorneys' fees and expenses of investigation and defense
incurred or suffered by you and your designees directly or indirectly, as a
result of any of your actions or omissions or those of your designees while
acting in good faith and in the exercise of your judgment under the Agreement,
these Joint Escrow Instructions, exhibits hereto or written instructions from
the Company or Purchaser hereunder.

     9. You are hereby expressly authorized to disregard any and all warnings
given by any of the parties hereto or by any other person or corporation,
excepting only orders or process of courts of law, and are hereby expressly
authorized to comply with and obey orders judgments or decrees of any court. In
case you obey or comply with any such order, judgment or decree, you shall not
be liable to any of the parties hereto or to any or to any other person, firm or
corporation by reason of such compliance, notwithstanding any such order,
judgment or decree being subsequently reversed, modified, annulled, set aside,
vacated or found to have been entered without jurisdiction.

     10. You shall not be liable in any respect on account of the identity,
authorities or rights of the parties executing or delivering or purporting to
execute or deliver the Agreement or any documents or papers deposited or called
for hereunder.

     11. You shall not be liable for the outlawing of any rights under the
Statute of Limitations with respect to these Joint Escrow Instructions or any
documents deposited with you.

     12. You shall be entitled to employ such legal counsel and other experts as
you may deem necessary properly to advise you in connection with your
obligations hereunder, may rely upon the advice of such counsel, and may pay
such counsel reasonable compensation therefor. The Company shall reimburse you
for any such disbursements.


                                      -2-

<PAGE>

     13. Your responsibilities as Escrow Agent hereunder shall terminate if you
shall resign by written notice to each party. In the event of any such
termination, the Company shall appoint a successor Escrow Agent.

     14. You are expressly authorized to delegate your duties as Escrow Agent
hereunder to the law firm of Wilson Sonsini Goodrich & Rosati, P.C., or any
other law firm, which delegation, if any, shall survive your resignation as
Escrow Agent.

     15. If you reasonably require other or further instruments in connection
with these Joint Escrow Instructions or obligations in respect hereto, the
necessary parties hereto shall join in furnishing such instruments.

     16. It is understood and agreed that should any dispute arise with respect
to the delivery and/or ownership or right of possession of the securities held
by you hereunder, you are authorized and directed to retain in your possession
without liability to anyone all or any part of said securities until such
disputes shall have been settled either by mutual written agreement of the
parties concerned or by a final order, decree or judgment of a court of
competent jurisdiction after the time for appeal has expired and no appeal has
been perfected, but you shall be under no duty whatsoever to institute or defend
any such proceedings.

     17. Any notice required or permitted hereunder shall be given in writing
and shall be deemed effectively given upon personal delivery or 4 days following
deposit in the United States Post Office, by registered or certified mail with
postage and fees prepaid, addressed to each of the other parties thereunto
entitled at the following addresses, or at such other addresses as a party may
designate by written notice to each of the other parties hereto.

COMPANY:        Peter A. Thompson, MD, FACP
                President and Chief Executive Officer
                Trubion Pharmaceuticals, Inc.
                2401 4th Avenue, Suite 1050
                Seattle, Washington 98121

PURCHASER:      Lee Brettman, MD, FACP

                -------------------------------------

                -------------------------------------

ESCROW AGENT:   Hans van Houte
                Secretary
                Trubion Pharmaceuticals, Inc.
                2401 4th Avenue, Suite 1050
                Seattle, Washington 98121

     18. By signing these Joint Escrow Instructions, you become a party hereto
only for the purpose of said Joint Escrow Instructions; you do not become a
party to the Agreement.


                                      -3-

<PAGE>

     19. This instrument shall be binding upon and inure to the benefit of the
parties hereto, and their respective successors and permitted assigns.


                                      -4-

<PAGE>

                                        Very truly yours,

                                        TRUBION PHARMACEUTICALS, INC.
                                        a Delaware Corporation


                                        By:
                                            ------------------------------------
                                        Title: President and CEO


                                        PURCHASER:


                                        ----------------------------------------
                                        (Signature)

                                        Lee Brettman, MD, FACP


ESCROW AGENT:


-------------------------------------
Hans van Houte, Corporate Secretary

                  [SIGNATURE PAGE TO JOINT ESCROW INSTRUCTIONS]

<PAGE>

                                    EXHIBIT D

                       ELECTION UNDER SECTION 83(B) OF THE
                    INTERNAL REVENUE CODE OF 1986, AS AMENDED

     The undersigned taxpayer hereby elects, pursuant to Section 83(b) of the
Internal Revenue Code of 1986, as amended, to include in his or her gross income
for the current taxable year, the amount of any compensation taxable to him or
her in connection with his or her receipt of the property described below:

     1. The name, address, taxpayer identification number and taxable year of
the undersigned are as follows:

NAME OF TAXPAYER: Lee Brettman          SPOUSE:
                                                --------------------------------

TAXPAYER'S ADDRESS:
                    ------------------------------------------------------------

                    ------------------------------------------------------------

TAXPAYER ID#:                           SPOUSE'S ID #:
              -----------------------                  -------------------------

     2. The property with respect to which the election is made is described as
follows: 100,000 shares (the "Shares") of the Common Stock of Trubion
Pharmaceuticals, Inc. (the "Company").

     3. The date on which the property was transferred is: January ______, 2004.

     4. The property is subject to the following restrictions: The Shares may be
repurchased by the Company, or its assignee, upon the occurrence of certain
events. This right lapses with regard to a portion of the Shares over time.

     5. The fair market value at the time of transfer, determined without regard
to any restriction other than a restriction which by its terms will never lapse,
of such property is: $5,000.

     6. The amount, if any, paid for such property: $5,000.

     The undersigned has submitted a copy of this statement to the person for
whom the services were performed in connection with the undersigned's receipt of
the above-described property. The transferee of such property is the person
performing the services in connection with the transfer of said property.

     The undersigned understand(s) that tine foregoing election may not be
revoked except with the consent of the Commissioner.


Dated:
       ------------------------------   ----------------------------------------
                                        Lee Brettman, Taxpayer

The undersigned spouse of taxpayer joins in this election.


Dated:
       ------------------------------   ----------------------------------------
                                        Spouse of Taxpayer