Document:

<PAGE>
                                                                     Exhibit 4.7

NEITHER THIS WARRANT NOR THE SECURITIES ISSUABLE UPON EXERCISE OF THIS WARRANT
HAVE BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED. NO SALE OR
DISPOSITION MAY BE EFFECTED EXCEPT IN COMPLIANCE WITH RULE 144 UNDER SAID ACT OR
WITHOUT AN EFFECTIVE REGISTRATION STATEMENT RELATED THERETO OR AN OPINION OF
COUNSEL FOR THE HOLDER, SATISFACTORY TO THE COMPANY, THAT SUCH REGISTRATION IS
NOT REQUIRED UNDER THE ACT OR RECEIPT OF A NO-ACTION LETTER FROM THE SECURITIES
AND EXCHANGE COMMISSION.

                 WARRANT TO PURCHASE 1231 SHARES OF COMMON STOCK

                                                                October 28, 2002

THIS CERTIFIES THAT, for value received, GENERAL ELECTRIC CAPITAL CORPORATION
("Holder") is entitled to subscribe for and purchase One Thousand Two Hundred
Thirty One (1,231) shares of the fully paid and nonassessable Common Stock (the
"Shares") of Altus Biologics, Inc., a Massachusetts corporation (the "Company"),
at the Warrant Price (as hereinafter defined), subject to the provisions and
upon the terms and conditions hereinafter set forth. As used herein, the term
"Common Stock" shall mean the Company's presently authorized Common Stock, and
any stock into which such Common Stock may hereafter be converted or exchanged.

1. Warrant Price. The Warrant Price shall initially be Four and 27/100 dollars
($4.27) per share, subject to adjustment as provided in Section 7 below.

2. Conditions to Exercise. The purchase right represented by this Warrant may be
exercised at any time, or from time to time, in whole or in part during the term
commencing on the date hereof and ending at 5:00 P.M. Eastern time on the
seventh anniversary of the date of this Warrant.

3. Method of Exercise; Payment; Issuance of Shares; Issuance of New Warrant.

     (a) Cash Exercise. Subject to Section 2 hereof, the purchase right
represented by this Warrant may be exercised by the Holder hereof, in whole or
in part, by the surrender of this Warrant (with a duly executed Notice of
Exercise in the form attached hereto) at the principal office of the Company (as
set forth in Section 17 below) and by payment to the Company, by check, of an
amount equal to the then applicable Warrant Price per share multiplied by the
number of shares then being purchased. In the event of any exercise of the
rights represented by this Warrant, certificates for the shares of stock so
purchased shall be in the name of, and delivered to, the Holder hereof, or as
such Holder may direct (subject to the terms of transfer contained herein and
upon payment by such Holder hereof of any applicable transfer taxes). Such
delivery shall be made within 30 days after exercise of the Warrant and at the
Company's expense and, unless this Warrant has been fully exercised or expired,
a new Warrant having terms and conditions substantially identical to this
Warrant and representing the portion of the Shares, if any, with respect to
which this Warrant shall not have been exercised, shall also be issued to the
Holder hereof within 30 days after exercise of the Warrant.

<PAGE>

     (b) Net Issue Exercise. In lieu of exercising this Warrant pursuant to
Section 3(a), Holder may elect to receive shares equal to the value of this
Warrant (or of any portion thereof remaining unexercised) by surrender of this
Warrant at the principal office of the Company together with notice of such
election, in which event the Company shall issue to Holder the number of shares
of the Company's Common Stock computed using the following formula:

X = Y (A-B)
    -------
       A

     Where X = the number of shares of Common Stock to be issued to Holder

     Y =  the number of shares of Common Stock purchasable under this Warrant
          (at the date of such calculation).

     A =  the Fair Market Value of one share of the Company's Common Stock (at
          the date of such calculation).

     B =  Warrant Price (as adjusted to the date of such calculation).

     (c) Fair Market Value. For purposes of this Section 3, Fair Market Value of
one share of the Company's Common Stock shall mean:

          (i) In the event of an exercise in connection with an Initial Public
     Offering, the per share Fair Market Value for the Common Stock shall be the
     Offering Price at which the underwriters initially sell Common Stock to the
     public; or

          (ii) The average of the closing bid and asked prices of Common Stock
     quoted in the Over-The-Counter Market Summary, or the last reported sale
     price of the Common Stock quoted on the Nasdaq National Market ("NNM") or
     on any exchange on which the Common Stock is listed, whichever is
     applicable, as published in the Wall Street Journal for the ten (10)
     trading days prior to the date of determination of Fair Market Value; or

          (iii) In the event of an exercise in connection with a merger,
     acquisition or other consolidation in which the Company is not the
     surviving entity, the per share Fair Market Value for the Common Stock
     shall be the value to be received per share of Common Stock by all holders
     of the Common Stock in such transaction as determined by the Board of
     Directors; or

          (iv) In any other instance, the per share Fair Market Value for the
     Common Stock shall be as determined in good faith by the Company's Board of
     Directors.

     In the event of 3(c)(iii) or 3(c)(iv), above, the Company's Board of
     Directors shall prepare a certificate, to be signed by an authorized
     officer of the Company, setting forth in reasonable detail the basis for
     and method of determination of the per share Fair Market Value of the
     Common Stock. The Board will also certify to the Holder that this per share
     Fair Market Value will be applicable to all holders of the Company's Common
     Stock. Such certification must be made to Holder at least thirty (30)
     business days prior

                                       2

<PAGE>

     to the proposed effective date of the merger, consolidation, sale, or other
     triggering event as defined in 3(c)(iii) or 3(c)(iv).

     (d) Automatic Exercise. To the extent this Warrant is not previously
exercised, it shall be automatically exercised in accordance with Sections 3(b)
and 3(c) hereof (even if not surrendered) immediately before its expiration.

4. Representations and Warranties of Holder and Restrictions on Transfer Imposed
by the Securities Act of 1933.

     (a) Representations and Warranties by Holder. The Holder represents and
warrants to the Company with respect to this purchase as follows:

          (i) The Holder has substantial experience in evaluating and investing
     in private placement transactions of securities of companies similar to the
     Company so that the Holder is capable of evaluating the merits and risks of
     its investment in the Company and has the capacity to protect its
     interests.

          (ii) The Holder is acquiring the Warrant and the Shares of Common
     Stock issuable upon exercise of the Warrant (collectively the "Securities")
     for investment for its own account and not with a view to, or for resale in
     connection with, any distribution thereof. The Holder understands that the
     Securities have not been registered under the Securities Act of 1933, as
     amended (the "Act") by reason of a specific exemption from the registration
     provisions of the Act which depends upon, among other things, the bona fide
     nature of the investment intent as expressed herein. In this connection,
     the Holder understands that, in the view of the Securities and Exchange
     Commission (the "SEC"), the statutory basis for such exemption may be
     unavailable if this representation was predicated solely upon a present
     intention to hold the Securities for the minimum capital gains period
     specked under tax statutes, for a deferred sale, for or until an increase
     or decrease in the market price of the Securities or for a period of one
     year or any other fixed period in the future.

          (iii) The Holder acknowledges that the Securities must be held
     indefinitely unless subsequently registered under the Act or an exemption
     from such registration is available. The Holder is aware of the provisions
     of Rule 144 promulgated under the Act ("Rule 144") which permits limited
     resale of securities purchased in a private placement subject to the
     satisfaction of certain conditions, including, in case the securities have
     been held for more than one but less than two years, the existence of a
     public market for the shares, the availability of certain public
     information about the Company, the resale occurring not less than one year
     after a party has purchased and paid for the security to be sold, the sale
     being through a "broker's transaction" or in a transaction directly with a
     "market maker (as provided by Rule 144(f,)) and the number of shares or
     other securities being sold during any three-month period not exceeding
     specified limitations.

          (iv) The Holder further understands that at the time the Holder wishes
     to sell the Securities there may be no public market upon which such a sale
     may be effected, and that even if such a public market exists, the Company
     may not be satisfying the current

                                       3

<PAGE>

     public information requirements of Rule 144, and that in such event, the
     Holder may be precluded from selling the Securities under Rule 144 unless
     (a) a one-year minimum holding period has been satisfied and (b) the Holder
     was not at the time of the sale nor at any time during the three-month
     period prior to such sale an affiliate of the Company.

          (v) The Holder has had an opportunity to discuss the Company's
     business, management and financial affairs with its management and an
     opportunity to review the Company's facilities. The Holder understands that
     such discussions, as well as the written information issued by the Company,
     were intended to describe the aspects of the Company's business and
     prospects which it believes to be material but were not necessarily a
     thorough or exhaustive description.

     (b) Legends. Each certificate representing the Securities shall be endorsed
with the following legend:

          THESE SECURITIES HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF
          1933 AND MAY NOT BE TRANSFERRED UNLESS COVERED BY AN EFFECTIVE
          REGISTRATION STATEMENT UNDER SAID ACT, A "NO ACTION" LETTER FROM THE
          SECURITIES AND EXCHANGE COMMISSION WITH RESPECT TO SUCH TRANSFER, A
          TRANSFER MEETING THE REQUIREMENTS OF RULE 144 OF THE SECURITIES AND
          EXCHANGE COMMISSION, OR (IF REASONABLY REQUIRED BY THE COMPANY) AN
          OPINION OF COUNSEL SATISFACTORY TO THE ISSUER TO THE EFFECT THAT ANY
          SUCH TRANSFER IS EXEMPT FROM SUCH REGISTRATION.

The Company need not enter into its stock records a transfer of Securities
unless the conditions specified in the foregoing legend are satisfied. The
Company may also instruct its transfer agent not to allow the transfer of any of
the Shares unless the conditions specified in the foregoing legend are
satisfied.

     (c) Removal of Legend and Transfer Restrictions. The legend relating to the
Act endorsed on a certificate pursuant to paragraph 4(b) of this Warrant shall
be removed and the Company shall issue a certificate without such legend to the
Holder of the Securities if (i) the Securities are registered under the Act and
a prospectus meeting the requirements of Section 10 of the Act is available or
(ii) the Holder provides to the Company an opinion of counsel for the Holder
reasonably satisfactory to the Company, a no-action letter or interpretive
opinion of the staff of the SEC reasonably satisfactory to the Company or other
evidence reasonably satisfactory to the Company, to the effect that public sale,
transfer or assignment of the Securities may be made without registration and
without compliance with any restriction such as Rule 144.

5. Condition of Transfer or Exercise of Warrant. It shall be a condition to any
transfer or exercise of this Warrant that at the time of such transfer or
exercise, the Holder shall provide the Company with a representation in writing
that the Holder or transferee is acquiring this Warrant and the shares of Common
Stock to be issued upon exercise for investment purposes only and

                                       4

<PAGE>

not with a view to any sale or distribution, or will provide the Company with a
statement of pertinent facts covering any proposed distribution. As a further
condition to any transfer of this Warrant or any or all of the shares of Common
Stock issuable upon exercise of this Warrant, other than a transfer registered
under the Act, the Company may request a legal opinion, in form and substance
satisfactory to the Company and its counsel, reciting the pertinent
circumstances surrounding the proposed transfer and stating that such transfer
is exempt from the registration and prospectus delivery requirements of the Act.
Each certificate evidencing the shares issued upon exercise of the Warrant or
upon any transfer of the shares (other than a transfer registered under the Act
or any subsequent transfer of shares so registered) shall, at the Company's
option, if the Shares are not freely saleable under Rule 144(k) under the Act,
contain a legend in form and substance satisfactory to the Company and its
counsel, restricting the transfer of the shares to sales or other dispositions
exempt from the requirements of the Act.

     As further condition to each transfer, at the request of the Company, the
Holder shall surrender this Warrant to the Company and the transferee shall
receive and accept a Warrant, of like tenor and date, executed by the Company.

6. Stock Fully Paid; Reservation of Shares. All Shares which may be issued upon
the exercise of the rights represented by this Warrant will, upon issuance, be
fully paid and nonassessable, and free from all taxes, liens, and charges with
respect to the issue thereof. During the period within which the rights
represented by this Warrant may be exercised, the Company will at all times have
authorized, and reserved for issuance upon exercise of the purchase rights
evidenced by this Warrant, a sufficient number of shares of its Common Stock to
provide for the exercise of the rights represented by this Warrant.

7. Adjustment for Certain Events. The number and kind of securities purchasable
upon the exercise of this Warrant and the Warrant Price shall be subject to
adjustment from time to time upon the occurrence of certain events, as follows:

     (a) Reclassification or Merger. In case of any reclassification or change
of securities of the class issuable upon exercise of this Warrant (other than a
change in par value, or from par value to no par value, or from no par value to
par value, or as a result of a subdivision or combination), or in case of any
merger of the Company with or into another corporation (other than a merger with
another corporation in which the Company is the acquiring and the surviving
corporation and which does not result in any reclassification or change of
outstanding securities issuable upon exercise of this Warrant), or in case of
any sale of all or substantially all of the assets of the Company, the Company,
or such successor or purchasing corporation, as the case may be, shall duly
execute and deliver to the Holder a new Warrant (in form and substance
satisfactory to the Holder of this Warrant), or the Company shall make
appropriate provision without the issuance of a new Warrant, so that the Holder
shall have the right to receive, at a total purchase price not to exceed that
payable upon the exercise of the unexercised portion of this Warrant, and in
lieu of the shares of Common Stock theretofore issuable upon exercise of this
Warrant, the kind and amount of shares of stock, other securities, money and
property receivable upon such reclassification, change, merger or sale by a
Holder of the number of shares of Common Stock then purchasable under this
Warrant, or in the case of such a merger or sale in which the consideration paid
consists all or in part of assets other than securities of the successor or

                                       5

<PAGE>

purchasing corporation, at the option of the Holder, the securities of the
successor or purchasing corporation having a value at the time of the
transaction equivalent to the value of the Common Stock purchasable upon
exercise of this Warrant at the time of the transaction. Any new Warrant shall
provide for adjustments that shall be as nearly equivalent as may be practicable
to the adjustments provided for in this Section 7. The provisions of this
subparagraph (a) shall similarly apply to successive reclassifications, changes,
mergers and transfers.

     (b) Subdivision or Combination of Shares. If the Company at any time while
this Warrant remains outstanding and unexpired shall subdivide or combine its
outstanding shares of Common Stock, the Warrant Price shall be proportionately
decreased and the number of Shares issuable hereunder shall be proportionately
increased in the case of a subdivision and the Warrant Price shall be
proportionately increased and the number of Shares issuable hereunder shall be
proportionately decreased in the case of a combination.

     (c) Stock Dividends and Other Distributions. If the Company at any time
while this Warrant is outstanding and unexpired shall (i) pay a dividend with
respect to Common Stock payable in Common Stock, then the Warrant Price shall be
adjusted, from and after the date of determination of shareholders entitled to
receive such dividend or distribution, to that price determined by multiplying
the Warrant Price in effect immediately prior to such date of determination by a
fraction (A) the numerator of which shall be the total number of shares of
Common Stock outstanding immediately prior to such dividend or distribution, and
(B) the denominator of which shall be the total number of shares of Common Stock
outstanding immediately after such dividend or distribution; or (ii) make any
other distribution with respect to Common Stock (except any distribution
specifically provided for in Sections 7(a) and 7(b)), then, in each such case,
provision shall be made by the Company such that the Holder of this Warrant
shall receive upon exercise of this Warrant a proportionate share of any such
dividend or distribution as though it were the Holder of the Common Stock (or
Common Stock issuable upon conversion thereof) as of the record date fixed for
the determination of the shareholders of the Company entitled to receive such
dividend or distribution.

     (d) Adjustment of Number of Shares. Upon each adjustment in the Warrant
Price, the number of Shares purchasable hereunder shall be adjusted, to the
nearest whole share, to the product obtained by multiplying the number of Shares
purchasable immediately prior to such adjustment in the Warrant Price by a
fraction, the numerator of which shall be the Warrant Price immediately prior to
such adjustment and the denominator of which shall be the Warrant Price
immediately thereafter.

8. Notice of Adjustments. Whenever any Warrant Price or the kind or number of
securities issuable under this Warrant shall be adjusted pursuant to Section 7
hereof, the Company shall prepare a certificate signed by an officer of the
Company setting forth, in reasonable detail, the event requiring the adjustment,
the amount of the adjustment, the method by which such adjustment was
calculated, and the Warrant Price and number or kind of shares issuable upon
exercise of the Warrant after giving effect to such adjustment, and shall cause
copies of such certificate to be mailed (by certified or registered mail, return
receipt required, postage prepaid) within thirty (30) days of such adjustment to
the Holder of this Warrant as set forth in Section 17 hereof.

                                       6

<PAGE>

9. Transferability of Warrant. This Warrant is transferable on the books of the
Company at its principal office by the registered Holder hereof upon surrender
of this Warrant properly endorsed, subject to compliance with Section 5 and
applicable federal and state securities laws. The Company shall issue and
deliver to the transferee a new Warrant representing the Warrant so transferred.
Upon any partial transfer, the Company will issue and deliver to Holder a new
Warrant with respect to the Warrant not so transferred. Holder shall not have
any right to transfer any portion of this Warrant to any direct competitor of
the Company.

10. No Fractional Shares. No fractional share of Common Stock will be issued in
connection with any exercise hereunder, but in lieu of such fractional share the
Company shall make a cash payment therefor upon the basis of the Warrant Price
then in effect.

11. Charges, Taxes and Expenses. Issuance of certificates for shares of Common
Stock upon the exercise of this Warrant shall be made without charge to the
Holder for any United States or state of the United States documentary stamp tax
or other incidental expense with respect to the issuance of such certificate,
all of which taxes and expenses shall be paid by the Company, and such
certificates shall be issued in the name of the Holder.

12. No Shareholder Rights Until Exercise. This Warrant does not entitle the
Holder hereof to any voting rights or other rights as a shareholder of the
Company prior to the exercise hereof.

13. Registry of Warrant. The Company shall maintain a registry showing the name
and address of the registered Holder of this Warrant. This Warrant may be
surrendered for exchange or exercise, in accordance with its terms, at such
office or agency of the Company, and the Company and Holder shall be entitled to
rely in all respects, prior to written notice to the contrary, upon such
registry.

14. Loss Theft Destruction or Mutilation of Warrant. Upon receipt by the Company
of evidence reasonably satisfactory to it of the loss, theft, destruction or
mutilation of this Warrant, and, in the case of loss, theft, or destruction, of
indemnity reasonably satisfactory to it, and, if mutilated, upon surrender and
cancellation of this Warrant, the Company will execute and deliver a new
Warrant, having terms and conditions substantially identical to this Warrant, in
lieu hereof.

15. Miscellaneous.

     (a) Issue Date. The provisions of this Warrant shall be construed and shall
be given effect in all respect as if it had been issued and delivered by the
Company on the date hereof.

     (b) Successors. This Warrant shall be binding upon any successors or
assigns of the Company.

     (c) Governing Law. This Warrant shall be governed by and construed in
accordance with the laws of the State of Connecticut.

     (d) Headings. The headings used in this Warrant are used for convenience
only and are not to be considered in construing or interpreting this Warrant.

                                       7

<PAGE>

     (e) Saturdays, Sundays, Holidays. If the last or appointed day for the
taking of any action or the expiration of any right required or granted herein
shall be a Saturday or a Sunday or shall be a legal holiday in the State of
Connecticut, then such action may be taken or such right may be exercised on the
next succeeding day not a legal holiday.

16. No Impairment. The Company will not, by amendment of its Certificate of
Incorporation or any other voluntary action, avoid or seek to avoid the
observance or performance of any of the terms of this Warrant, but will at all
times in good faith assist in the carrying out of all such terms and in the
taking of all such action as may be necessary or appropriate in order to protect
the rights of the Holder hereof against impairment.

17. Addresses. Any notice required or permitted hereunder shall be in writing
and shall be mailed by overnight courier, registered or certified mail, return
receipt required, and postage prepaid, or otherwise delivered by hand or by
messenger, addressed as set forth below, or at such other address as the Company
or the Holder hereof shall have furnished to the other party.

          If to the Company: ALTUS BIOLOGICS, INC.
                             625 Putnam Avenue
                             Cambridge, MA 02139-4807
                             Attn: John Ledoux

          If to the Holder:  GENERAL ELECTRIC CAPITAL CORPORATION
                             401 Merritt 7, Suite 23
                             Norwalk, CT 06856
                             Attn: Thomas Annino

IN WITNESS WHEREOF, ALTUS BIOLOGICS, INC. has caused this Warrant to be executed
by its officers thereunto duly authorized.

Dated as of October 28, 2002

                                        By: /s/ Peter Lanciano
                                            ------------------------------------
                                        Name: Peter Lanciano
                                        Title: President and CEO

                                        8<PAGE>
                                                                     Exhibit 4.8

THIS WARRANT, AND THE SECURITIES ISSUABLE HEREUNDER, HAVE NOT BEEN REGISTERED
UNDER THE SECURITIES ACT OF 1933, AS AMENDED, (THE "ACT') OR THE APPLICABLE
SECURITIES LAWS OF ANY STATE, AND MAY NOT BE SOLD, TRANSFERRED OR ASSIGNED
UNLESS REGISTERED UNDER THE ACT AND UNDER APPLICABLE STATE SECURITIES LAWS, OR
UNLESS AN OPINION OF COUNSEL, REASONABLY SATISFACTORY TO THE COMPANY, IS
OBTAINED TO THE EFFECT THAT SUCH SALE, TRANSFER, OR ASSIGNMENT IS EXEMPT FROM
THE REGISTRATION REQUIREMENTS OF THE ACT AND SUCH STATE SECURITIES LAWS.

                WARRANT TO PURCHASE 3,452 SHARES OF COMMON STOCK

                                                                   April 4, 2002

THIS CERTIFIES THAT, for value received, OXFORD FINANCE CORPORATION, ("Holder")
is entitled to subscribe for and purchase Three Thousand Four Hundred Fifty Two
(3,452) shares of the fully paid and nonassessable Common Stock ("the Shares")
of ALTUS BIOLOGICS. INC., a Massachusetts corporation (the "Company"), at the
Warrant Price (as hereinafter defined), subject to the provisions and upon the
terms and conditions hereinafter set forth. As used herein, the term "Common
Stock" shall mean the Company's presently authorized Common Stock, and any stock
into which such Common Stock may hereafter be exchanged.

1. Warrant Price. The Warrant Price shall initially be four and 0.2747100
dollars ($4.27471001) per share, subject to adjustment as provided in Section 7
below.

2. Conditions to Exercise. The purchase right represented by this Warrant may be
exercised at any time, or from time to time, in whole or in part during the term
commencing on the date hereof and ending on the earlier of:

     (a)  5:00 P.M. Eastern Standard time on the fifth annual anniversary of
          this Warrant Agreement; or

     (b)  The closing of the initial public offering of the Company's Common
          Stock pursuant to a registration statement under the Securities Act of
          1933, as amended (the "Initial Public Offering"). The Company shall
          provide notice of the Initial Public Offering to the Holder at least
          30 days prior to the closing thereof; or

     (c)  The effective date of the merger of the Company with or into, the
          consolidation of the Company with, or the sale by the Company of all
          or substantially all of its assets or all or substantially all of its
          shares to another corporation or other entity (other than such a
          transaction wherein the shareholders of the Company retain or obtain a
          majority of the voting capital stock of the surviving, resulting, or
          purchasing corporation); provided that the Company shall notify the
          registered Holder of this Warrant of the proposed effective date of
          the merger, consolidation, or sale at least 30 days prior to the
          effectiveness thereof.

In the event that, although the Company shall have given notice of a transaction
pursuant to subparagraph (b) or subparagraph (c) hereof, the transaction does
not close within 120 days of
<PAGE>
the day specified by the Company, unless otherwise elected by the Holder any
exercise of the Warrant subsequent to the giving of such notice shall be
rescinded and the Warrant shall again be exercisable until terminated in
accordance with this Paragraph 2.

3. Method of Exercise: Payment: Issuance of Shares: Issuance of New Warrant.

     (a)  Cash Exercise. Subject to Section 2 hereof, the purchase right
          represented by this Warrant may be exercised by the Holder hereof, in
          whole or in part, by the surrender of this Warrant (with a duly
          executed Notice of Exercise in the form attached hereto) at the
          principal office of the Company (as set forth in Section 18 below) and
          by payment to the Company, by check, of an amount equal to the then
          applicable Warrant Price per share multiplied by the number of shares
          then being purchased. In the event of any exercise of the rights
          represented by this Warrant, certificates for the shares of stock so
          purchased shall be in the name of, and delivered to, the Holder
          hereof, or as such Holder may direct (subject to the terms of transfer
          contained herein and upon payment by such Holder hereof of any
          applicable transfer taxes). Such delivery shall be made within 10 days
          after exercise of the Warrant and at the Company's expense and, unless
          this Warrant has been fully exercised or expired, a new Warrant having
          terms and conditions substantially identical to this Warrant and
          representing the portion of the Shares, if any, with respect to which
          this Warrant shall not have been exercised, shall also be issued to
          the Holder hereof within 10 days after exercise of the Warrant.

     (b)  Net Issue Exercise. In lieu of exercising this Warrant pursuant to
          Section 3(a), Holder may elect to receive shares equal to the value of
          this Warrant (or of any portion thereof remaining unexercised) by
          surrender of this Warrant at the principal office of the Company
          together with notice of such election, in which event the Company
          shall issue to Holder the number of shares of the Company's Common
          Stock computed using the following formula:

               X = Y (A-B)
                   -------
                      A

               Where X = the number of shares of Common Stock to be issued to
               Holder.

               Y = the number of shares of Common Stock purchasable under this
               Warrant (at the date of such calculation).

               A = the Fair Market Value of one share of the Company's Common
               Stock (at the date of such calculation).

               B = Warrant Price (as adjusted to the date of such calculation).

     (c)  Fair Market Value. For purposes of this Section 3, Fair Market Value
          of one share of the Company's Common Stock shall mean:

          (i)  In the event of an exercise in connection with an Initial Public
               Offering, the per share Fair Market Value for the Common Stock
               shall be the
<PAGE>
               Offering Price at which the underwriters initially sell Common
               Stock to the public; or

          (ii) The average of the closing bid and asked prices of the Common
               Stock quoted in the Over-The-Counter Market Summary, or the
               average of, the last reported sale price of the Common Stock or
               the closing price quoted on the Nasdaq National Market System
               ("NMS") or on any exchange on which the Common Stock is listed,
               whichever is applicable, as published in The Wall Street Journal
               over the ten (10) trading days prior to the date of determination
               of fair market value; or

          (iii) In the event of an exercise in connection with a merger,
               acquisition or other consolidation in which the Company is not
               the surviving entity, as described in Section 2(c), the per share
               Fair Market Value for the Common Stock shall be the value to be
               received per share of Common Stock by all holders of the Common
               Stock in such transaction as determined by the Board of
               Directors; or

          (iv) If the Common Stock is not publicly traded, the per share fair
               market value of the Common Stock shall be as determined in good
               faith by the Company's Board of Directors unless Holder elects to
               have such fair market value determined by an appraiser, which
               election must be made by Holder within ten (10) business days of
               the date the Company notifies Holder of the fair market value as
               determined by its Board of Directors. In the event of such an
               appraisal, the cost thereof shall be borne by the Holder unless
               such appraisal results in a fair market value in excess of 115%
               of that determined by the Company's Board of Directors, in which
               event the Company shall bear the cost of such appraisal.

     In the event of 3(c)(iii) or 3(c)(iv), above, the Company's Board of
     Directors shall prepare a certificate, to be signed by an authorized
     Officer of the Company, setting forth in reasonable detail the basis for
     and method of determination of the per share Fair Market Value of the
     Common Stock. The Board will also certify to the Holder that this per share
     Fair Market Value will be applicable to all holders of the Company's Common
     Stock. Such certification must be made to Holder at least thirty (30)
     business days prior to the proposed effective date of the merger,
     consolidation, sale, or other triggering event as defined in 3(c)(iii) and
     3(c)(iv).

     (d)  Automatic Exercise. To the extent this Warrant is not previously
          exercised, it shall be automatically exercised in accordance with
          Sections 3(b) and 3(c) hereof immediately before: (i) its expiration,
          or (ii) the consummation of any consolidation or merger of the
          Company, or any sale or transfer of a majority of the Company's assets
          or stock pursuant to Section 2(b).

4. Representations and Warranties of Holder and Restrictions on Transfer Imposed
by the Securities Act of 1933.
<PAGE>
     (a)  Representations and Warranties by Holder. The Holder represents and
          warrants to the Company with respect to this purchase as follows:

          (i)  The Holder has substantial experience in evaluating and investing
               in private placement transactions of securities of companies
               similar to the Company so that the Holder is capable of
               evaluating the merits and risks of its investment in the Company
               and has the capacity to protect its interests.

          (ii) The Holder is acquiring the Warrant and the Shares of Common
               Stock issuable upon exercise of the Warrant (collectively the
               "Securities") for investment for its own account and not with a
               view to, or for resale in connection with, any distribution
               thereof. The Holder understands that the Securities have not been
               registered under the Securities Act of 1933, as amended (the
               "Act") by reason of a specific exemption from the registration
               provisions of the Act which depends upon, among other things, the
               bona fide nature of the investment intent as expressed herein. In
               this connection, the Holder understands that, in the view of the
               Securities and Exchange Commission (the "SEC"), the statutory
               basis for such exemption may be unavailable if this
               representation was predicated solely upon a present intention to
               hold the Securities for the minimum capital gains period
               specified under tax statutes, for a deferred sale, for or until
               an increase or decrease in the market price of the Securities or
               for a period of one year or any other fixed period in the future.

          (iii) The Holder acknowledges that the Securities must be held
               indefinitely unless subsequently registered under the Act or an
               exemption from such registration is available. The Holder is
               aware of the provisions of Rule 144 promulgated under the Act
               ("Rule 144") which permits limited resale of securities purchased
               in a private placement subject to the satisfaction of certain
               conditions, including, in case the securities have been held for
               more than one but less than two years, the existence of a public
               market for the shares, the availability of certain public
               information about the Company, the resale occurring not less than
               one years after a party has purchased and paid for the security
               to be sold, the sale being through a "broker's transaction" or in
               a transaction directly with a "market maker" (as provided by Rule
               144(f)) and the number of shares or other securities being sold
               during any three-month period not exceeding specified
               limitations.

          (iv) The Holder further understands that at the time the Holder wishes
               to sell the Securities there may be no public market upon which
               such a sale may be effected, and that even if such a public
               market exists, the Company may not be satisfying the current
               public information requirements of Rule 144, and that in such
               event, the Holder may be precluded from selling the Securities
               under Rule 144 unless a) a one-year minimum holding period has
               been satisfied and b) the Holder was not at the time of the sale
               nor at
<PAGE>
               any time during the three-month period prior to such sale an
               affiliate of the Company.

          (v)  The Holder has had an opportunity to discuss the Company's
               business, management and financial affairs with its management
               and an opportunity to review the Company's facilities. The Holder
               understands that such discussions, as well as the written
               information issued by the Company, were intended to describe the
               aspects of the Company's business and prospects which it believes
               to be material but were not necessarily a thorough or exhaustive
               description.

     (b)  Legends. Each certificate representing the Securities shall be
          endorsed with the following legend:

          THESE SECURITIES HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF
          1933, AS AMENDED, (THE "ACT") OR THE APPLICABLE SECURITIES LAWS OF ANY
          STATE, AND MAY NOT BE SOLD, TRANSFERRED OR ASSIGNED UNLESS REGISTERED
          UNDER THE ACT AND UNDER APPLICABLE STATE SECURITIES LAWS, OR UNLESS AN
          OPINION OF COUNSEL, REASONABLY SATISFACTORY TO THE COMPANY, IS
          OBTAINED TO THE EFFECT THAT SUCH SALE, TRANSFER, OR ASSIGNMENT IS
          EXEMPT FROM THE REGISTRATION REQUIREMENTS OF THE ACT AND SUCH STATE
          SECURITIES LAWS

     The Company need not enter into its stock register a transfer of
     Securities. unless the conditions specified in the foregoing legend are
     satisfied. The Company may also instruct its transfer agent not to register
     the transfer of any of the Shares unless the conditions specified in the
     foregoing legend are satisfied.

     (c)  Removal of Legend and Transfer Restrictions. The legend relating to
          the Act endorsed on a certificate pursuant to paragraph 4(b) of this
          Warrant and the stop transfer instructions with respect to the
          Securities represented by such certificate shall be removed and the
          Company shall issue a certificate without such legend to the Holder of
          the Securities if, in the opinion of the Company's counsel, the public
          sale, transfer or assignment of the Securities may be made without
          registration and without compliance with any restriction such as Rule
          144.

5. Condition of Transfer or Exercise of Warrant. It shall be a condition to any
transfer or exercise of this Warrant that at the time of such transfer or
exercise, the Holder shall provide the Company with a representation in writing
that the Holder or transferee is acquiring this Warrant and the shares of Common
Stock to be issued upon exercise, for investment purposes only and not with a
view to any sale or distribution, and will provide the Company with a statement
of pertinent facts covering any proposed distribution. As a further condition to
any transfer of this Warrant or any or all of the shares of Common Stock
issuable upon exercise of this Warrant, other than a transfer registered under
the Act, the Company must have received a legal opinion, in form and substance
satisfactory to the Company and its counsel, reciting the pertinent
circumstances surrounding the proposed transfer and stating that such transfer
is exempt from the
<PAGE>
registration and prospectus delivery requirements of the Act and applicable
state securities laws. Each certificate evidencing the shares issued upon
exercise of the Warrant or upon any transfer of the shares (other than a
transfer registered under the Act or any subsequent transfer of shares so
registered) shall, at the Company's option, contain a legend in form and
substance satisfactory to the Company and its counsel, restricting the transfer
of the shares to sales or other dispositions exempt from the requirements of the
Act and applicable state securities laws.

As further condition to each transfer, the Holder shall surrender this Warrant
to the Company and the transferee shall receive and accept a Warrant, of like
tenor and date, executed by the Company.

6. Stock Fully Paid: Reservation of Shares. All Shares, which may be issued upon
the exercise of the rights represented by this Warrant, will, upon issuance, be
fully paid and nonassessable, and free from all taxes, liens, and charges with
respect to the issue thereof. During the period within which the rights
represented by this Warrant may be exercised, the Company will at all times have
authorized, and reserved for issuance upon exercise of the purchase rights
evidenced by this Warrant, a sufficient number of shares of its Common Stock to
provide for the exercise of the rights represented by this Warrant.

7. Adjustment for Certain Events. In the event of changes in the outstanding
Common Stock by reason of stock dividends, split-ups, recapitalizations,
reclassifications, mergers, consolidations, combinations or exchanges of shares,
separations, reorganizations, liquidations, or the like, the number and class of
shares available under the Warrant in the aggregate and the Warrant Price shall
be correspondingly adjusted, as appropriate, by the Board of Directors of the
Company. The adjustment shall be such as will give the Holder of this Warrant
upon exercise for the same aggregate Warrant Price the total number, class and
kind of shares as he would have owned had the Warrant been exercised prior to
the event and had he continued to hold such shares until after the event
requiring adjustment.

8. Notice of Adjustments. Whenever any Warrant Price shall be adjusted pursuant
to Section 7 hereof, the Company shall prepare a certificate signed by an
officer of the Company's chief financial officer setting forth, in reasonable
detail, the event requiring the adjustment, the amount of the adjustment, the
method by which such adjustment was calculated, and the Warrant Price and number
of shares issuable upon exercise of the Warrant after giving effect to such
adjustment, and shall cause copies of such certificate to be mailed (by
certified or registered mail, return receipt required, postage prepaid) within
thirty (30) days of such adjustment to the Holder of this Warrant as set forth
in Section 18 hereof.

9. Market Stand-Off Agreement. Holder hereby agrees that for a period of up to
180 days following the effective date of the first registration statement of the
Company covering common stock (and/or other securities) to be sold on its behalf
of the Company in an underwritten public offering, it will not, to the extent
requested by the Company and any underwriter, sell or otherwise transfer or
dispose of (other than to donees who agree to be similarly bound) any of the
Shares at any time during such period except common stock included. in such
registration.

10. Transferability of Warrant. This Warrant is transferable on the books of the
Company at its principal office by the registered Holder hereof upon surrender
of this Warrant properly
<PAGE>
endorsed, subject to compliance with Section 5 and applicable federal and state
securities laws. The Company shall issue and deliver to the transferee a new
Warrant representing the Warrant so transferred. Upon any partial transfer, the
Company will issue and deliver to Holder a new Warrant with respect to the
Warrant not so transferred. Holder shall not have any right to transfer any
portion of this Warrant to any direct competitor of the Company.

11. No Fractional Shares. No fractional share of Common Stock will be issued in
connection with any exercise hereunder, but in lieu of such fractional share the
Company shall make a cash payment therefor upon the basis of the Warrant Price
then in effect.

12. Charges, Taxes and Expenses. Issuance of certificates for shares of Common
Stock upon the exercise of this Warrant shall be made without charge to the
Holder for any Federal or state documentary stamp tax or other incidental
expense within respect to the issuance of such certificate, which taxes and
expenses shall be paid by the Company, and such certificates shall be issued in
the name of the Holder.

13. No Shareholder Rights Until Exercise. This Warrant does not entitle the
Holder hereof to any voting rights or other rights as a shareholder of the
Company prior to the exercise hereof.

14. Registry of Warrant. The Company shall maintain a registry showing the name
and address of the registered Holder of this Warrant. This Warrant may be
surrendered for exchange or exercise, in accordance with its terms, at such
office or agency of the Company, and the Company and Holder shall be entitled to
rely in all respects, prior to written notice to the contrary, upon such
registry.

15. Loss, Theft. Destruction or Mutilation of Warrant. Upon receipt by the
Company of evidence reasonably satisfactory to it of the loss, theft,
destruction or mutilation of this Warrant, and, in the case of loss, theft, or
destruction, of indemnity reasonably satisfactory to it, and, if mutilated, upon
surrender and cancellation of this Warrant, the Company will execute and deliver
a new Warrant, having terms and conditions substantially identical to this
Warrant, in lieu hereof

16. Miscellaneous.

     (a)  Issue Date. The provisions of this Warrant shall be construed and
          shall be given effect in all respect as if it had been issued and
          delivered by the Company on the date hereof.

     (b)  Successors. This Warrant shall be binding upon any successors or
          assigns of the Company.

     (c)  Governing Law. This Warrant shall be governed by and construed in
          accordance with the laws of the State of Massachusetts.

     (d)  Headings. The headings used in this Warrant are used for convenience
          only and are not to be considered in construing or interpreting this
          Warrant.
<PAGE>
     (e)  Saturdays, Sundays, Holidays. If the last or appointed day for the
          taking of any action or the expiration of any right required or
          granted herein shall be a Saturday or a Sunday or shall be a legal
          holiday in the State of Massachusetts, then such action may be taken
          or such right may be exercised on the next succeeding day not a legal
          holiday.

17. No Impairment. The Company will not, by amendment of its Articles of
Incorporation or any other voluntary action, avoid or seek to avoid the
observance or performance of any of the terms of this Warrant, but will at all
times in good faith assist in the carrying out of all such terms and in the
taking of all such action as may be necessary or appropriate in order to protect
the rights of the Holder hereof against impairment.

18. Addresses. Any notice required or permitted hereunder shall be in writing
and shall be mailed by overnight courier, registered or certified mail, return
receipt required, and postage pre-paid, or otherwise delivered by hand or by
messenger, addressed as set forth below, or at such other address as the Company
or the Holder hereof shall have furnished to the other party.

          If to the Company: Altus Biologics, Inc.
                             625 Putnam Avenue
                             Cambridge, MA 02139
                             Attn: Mr. Peter Lanciano, President & CEO

          If to the Holder:  Oxford Finance Corporation 133 N. Fairfax Street
                             Alexandria, VA 22314
                             Attn: J. Alden Philbrick, President

N WITNESS WHEREOF, ALTUS BIOLOGICS, INC. has caused this Warrant to be executed
by its officers thereunto duly authorized.

Dated as of April 4 2002.

By: /s Peter Lanciano
    ---------------------------------
Name: Peter Lanciano
Title: President & CEO

Source: [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00091-of-00352.parquet"}, [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00091-of-00352.parquet"}]]