EXHIBIT
4.12

     

    MICROMET, INC.

     

    and

     

    ________,
AS WARRANT AGENT

     

    FORM
OF DEBT SECURITIES

    WARRANT
AGREEMENT

     

    DATED
AS OF [__], 20___


    
      
        
        

         


      

      
         

        
          

        

      

      
         


      

    


    MICROMET, INC.

     

    FORM
OF DEBT SECURITIES WARRANT AGREEMENT

     

    Debt
Securities Warrant Agreement (this “Agreement”),
dated as of                     
between Micromet, Inc.,
a Delaware corporation (the “Company”)
and                     ,
a [corporation] [national banking association] organized and existing under the
laws of                     
and having a corporate trust office in                     ,
as warrant agent (the “Warrant
Agent”).

     

    Whereas,
the Company has entered into an indenture dated as of [                     
(the “Senior
Indenture”), with                     ,
as trustee (such trustee, and any successors to such trustee, herein called the
“Senior
Trustee”), providing for the issuance from time to time of its
unsubordinated debt securities, to be issued in one or more series as provided
in the Senior Indenture (the “Debt
Securities”);] [                    
(the “Subordinated
Indenture”), with                     ,
as trustee (such trustee, and any successors to such trustee, herein called the
“Subordinated
Trustee”), providing for the issuance from time to time of its
subordinated debt securities, to be issued in one or more series as provided in
the Subordinated Indenture (the “Debt
Securities”);]

     

    Whereas,
the Company proposes to sell [If Warrants are sold with other
securities—title of such other securities being offered (the “Other
Securities”) with] warrant certificates evidencing one or more warrants
(the “Warrants”
or, individually, a “Warrant”)
representing the right to purchase [title of Debt Securities purchasable through
exercise of Warrants] (the “Warrant Debt
Securities”), such warrant certificates and other warrant certificates
issued pursuant to this Agreement being herein called the “Warrant
Certificates”; and

     

    Whereas,
the Company desires the Warrant Agent to act on behalf of the Company,
and the Warrant Agent is willing so to act, in connection with the issuance,
registration, transfer, exchange, exercise and replacement of the Warrant
Certificates, and in this Agreement wishes to set forth, among other things, the
form and provisions of the Warrant Certificates and the terms and conditions on
which they may be issued, registered, transferred, exchanged, exercised and
replaced.

     

    Now,
Therefore, in consideration of the premises and of the mutual agreements
herein contained, the parties hereto agree as follows:


    
      
         


      

      
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    ARTICLE
1

     

    ISSUANCE
OF WARRANTS AND EXECUTION AND DELIVERY OF WARRANT CERTIFICATES

     

    1.1           Issuance of Warrants. [If
Warrants alone—Upon issuance, each Warrant Certificate shall evidence one or
more Warrants.] [If Other Securities and Warrants—Warrant Certificates shall be
[initially] issued in connection with the issuance of the Other Securities [but
shall be separately transferable on and after                     
(the “Detachable
Date”)] [and shall not be separately transferable] and each Warrant
Certificate shall evidence one or more Warrants.] Each Warrant evidenced thereby
shall represent the right, subject to the provisions contained herein and
therein, to purchase one Warrant Debt Security. [If Other Securities and
Warrants—Warrant Certificates shall be initially issued in units with the Other
Securities and each Warrant Certificate included in such a unit shall evidence
                    
Warrants for each [$                
principal amount] [            
shares] of Other Securities included in such unit].

     

    1.2           Execution and Delivery of Warrant
Certificates. Each Warrant Certificate, whenever issued, shall be in
registered form substantially in the form set forth in Exhibit A hereto, shall be
dated the date of its countersignature by the Warrant Agent and may have such
letters, numbers, or other marks of identification or designation and such
legends or endorsements printed, lithographed or engraved thereon as the
officers of the Company executing the same may approve (execution thereof to be
conclusive evidence of such approval) and as are not inconsistent with the
provisions of this Agreement, or as may be required to comply with any law or
with any rule or regulation made pursuant thereto or with any rule or regulation
of any securities exchange on which the Warrants may be listed, or to conform to
usage. The Warrant Certificates shall be signed on behalf of the Company by any
of its present or future chief executive officers, presidents, senior vice
presidents, vice presidents, chief financial officers, chief legal officers,
treasurers, assistant treasurers, controllers, assistant controllers,
secretaries or assistant secretaries under its corporate seal reproduced
thereon. Such signatures may be manual or facsimile signatures of such
authorized officers and may be imprinted or otherwise reproduced on the Warrant
Certificates. The seal of the Company may be in the form of a facsimile thereof
and may be impressed, affixed, imprinted or otherwise reproduced on the Warrant
Certificates.

     

    No
Warrant Certificate shall be valid for any purpose, and no Warrant evidenced
thereby shall be exercisable, until such Warrant Certificate has been
countersigned by the manual signature of the Warrant Agent. Such signature by
the Warrant Agent upon any Warrant Certificate executed by the Company shall be
conclusive evidence that the Warrant Certificate so countersigned has been duly
issued hereunder.

     

    In case
any officer of the Company who shall have signed any of the Warrant Certificates
either manually or by facsimile signature shall cease to be such officer before
the Warrant Certificates so signed shall have been countersigned and delivered
by the Warrant Agent, such Warrant Certificates may be countersigned and
delivered notwithstanding that the person who signed Warrant Certificates ceased
to be such officer of the Company; and any Warrant Certificate may be signed on
behalf of the Company by such persons as, at the actual date of the execution of
such Warrant Certificate, shall be the proper officers of the Company, although
at the date of the execution of this Agreement any such person was not such
officer.

     

    The term
“holder” or “holder of a Warrant Certificate” as used herein shall mean any
person in whose name at the time any Warrant Certificate shall be registered
upon the books to be maintained by the Warrant Agent for that purpose [If Other
Securities and Warrants are not immediately detachable—or upon the registration
of the Other Securities prior to the Detachable Date. Prior to the Detachable
Date, the Company will, or will cause the registrar of the Other Securities to,
make available at all times to the Warrant Agent such information as to holders
of the Other Securities as may be necessary to keep the Warrant Agent’s records
up to date].


    
      
         


      

      
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    1.3           Issuance of Warrant
Certificates. Warrant Certificates evidencing the right to purchase
Warrant Debt Securities may be executed by the Company and delivered to the
Warrant Agent upon the execution of this Warrant Agreement or from time to time
thereafter. The Warrant Agent shall, upon receipt of Warrant Certificates duly
executed on behalf of the Company, countersign such Warrant Certificates and
shall deliver such Warrant Certificates to or upon the order of the
Company.

     

    ARTICLE
2

     

    WARRANT
PRICE, DURATION AND EXERCISE OF WARRANTS

     

    2.1           Warrant Price. During the
period specified in Section 2.2, each Warrant shall, subject to the terms of
this Warrant Agreement and the applicable Warrant Certificate, entitle the
holder thereof, to purchase the principal amount of Warrant Debt Securities
specified in the applicable Warrant Certificate at an exercise price of                     %
of the principal amount thereof [plus accrued amortization, if any, of the
original issue discount of the Warrant Debt Securities] [plus accrued interest,
if any, from the most recent date from which interest shall have been paid on
the Warrant Debt Securities or, if no interest shall have been paid on the
Warrant Debt Securities, from the date of their initial issuance.] [The original
issue discount ($         
for each $1,000 principal amount of Warrant Debt Securities) will be amortized
at a          %
annual rate, computed on a[n] [semi-] annual basis [using a 360-day year
consisting of twelve 30-day months].] Such purchase price for the Warrant Debt
Securities is referred to in this Agreement as the “Warrant
Price.”

     

    2.2           Duration of Warrants. Each
Warrant may be exercised in whole or in part at any time, as specified herein,
on or after [the date thereof] [                    ]
and at or before [                    ]
p.m., [City] time, on                     
or such later date as the Company may designate by notice to the Warrant Agent
and the holders of Warrant Certificates mailed to their addresses as set forth
in the record books of the Warrant Agent (the “Expiration
Date”). Each Warrant not exercised at or before [             ]
p.m., [City] time, on the Expiration Date shall become void, and all rights of
the holder of the Warrant Certificate evidencing such Warrant under this
Agreement shall cease.


    
      
         


      

      
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    2.3           Exercise
Of Warrants.

     

    (a)           During
the period specified in Section 2.2, the Warrants may be exercised to purchase a
whole number of Warrant Debt Securities in registered form by providing certain
information as set forth on the reverse side of the Warrant Certificate and by
paying in full, in lawful money of the United States of America, [in cash or by
certified check or official bank check in New York Clearing House funds] [by
bank wire transfer in immediately available funds] the Warrant Price for each
Warrant Debt Security with respect to which a Warrant is being exercised to the
Warrant Agent at its corporate trust office, provided that such exercise is
subject to receipt within five business days of such payment by the Warrant
Agent of the Warrant Certificate with the form of election to purchase Warrant
Debt Securities set forth on the reverse side of the Warrant Certificate
properly completed and duly executed. The date on which payment in full of the
Warrant Price is received by the Warrant Agent shall, subject to receipt of the
Warrant Certificate as aforesaid, be deemed to be the date on which the Warrant
is exercised; provided, however, that if, at the date of receipt of such Warrant
Certificates and payment in full of the Warrant Price, the transfer books for
the Warrant Debt Securities purchasable upon the exercise of such Warrants shall
be closed, no such receipt of such Warrant Certificates and no such payment of
such Warrant Price shall be effective to constitute the person so designated to
be named as the holder of record of such Warrant Debt Securities on such date,
but shall be effective to constitute such person as the holder of record of such
Warrant Debt Securities for all purposes at the opening of business on the next
succeeding day on which the transfer books for the Warrant Debt Securities
purchasable upon the exercise of such Warrants shall be opened, and the
certificates for the Warrant Debt Securities in respect of which such Warrants
are then exercised shall be issuable as of the date on such next succeeding day
on which the transfer books shall next be opened, and until such date the
Company shall be under no duty to deliver any certificate for such Warrant Debt
Securities. The Warrant Agent shall deposit all funds received by it in payment
of the Warrant Price in an account of the Company maintained with it and shall
advise the Company by telephone at the end of each day on which a payment for
the exercise of Warrants is received of the amount so deposited to its account.
The Warrant Agent shall promptly confirm such telephone advice to the Company in
writing.

     

    (b)           The
Warrant Agent shall, from time to time, as promptly as practicable, advise the
Company of (i) the number of Warrant Debt Securities with respect to which
Warrants were exercised, (ii) the instructions of each holder of the Warrant
Certificates evidencing such Warrants with respect to delivery of the Warrant
Debt Securities to which such holder is entitled upon such exercise, (iii)
delivery of Warrant Certificates evidencing the balance, if any, of the Warrants
for the remaining Warrant Debt Securities after such exercise, and (iv) such
other information as the Company or the [Senior] [Subordinated] Trustee shall
reasonably require.

     

    (c)           As
soon as practicable after the exercise of any Warrant, the Company shall issue,
pursuant to the Indenture, in authorized denominations, to or upon the order of
the holder of the Warrant Certificate evidencing such Warrant, the Warrant Debt
Securities to which such holder is entitled, in fully registered form,
registered in such name or names as may be directed by such holder. If fewer
than all of the Warrants evidenced by such Warrant Certificate are exercised,
the Company shall execute, and an authorized officer of the Warrant Agent shall
manually countersign and deliver, a new Warrant Certificate evidencing Warrants
for the number of Warrant Debt Securities remaining unexercised.

     

    (d)           The
Company shall not be required to pay any stamp or other tax or other
governmental charge required to be paid in connection with any transfer involved
in the issue of the Warrant Debt Securities, and in the event that any such
transfer is involved, the Company shall not be required to issue or deliver any
Warrant Debt Securities until such tax or other charge shall have been paid or
it has been established to the Company’s satisfaction that no such tax or other
charge is due.

     

    (e)           Prior
to the issuance of any Warrants there shall have been reserved, and the Company
shall at all times through the Expiration Date keep reserved, out of its
authorized but unissued Warrant Debt Securities, a number of shares sufficient
to provide for the exercise of the Warrants.


    
      
         


      

      
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    ARTICLE
3

     

    OTHER
PROVISIONS RELATING TO RIGHTS OF HOLDERS OF WARRANT CERTIFICATES

     

    3.1           No Rights As Holders of Warrant Debt
Securities Conferred By Warrants or Warrant Certificates. No Warrant
Certificate or Warrant evidenced thereby shall entitle the holder thereof to any
of the rights of a holder of Warrant Debt Securities, including, without
limitation, the right to receive the payment of principal of (or premium, if
any) or interest, if any, on the Warrant Debt Securities or to enforce any of
the covenants in the Indenture.

     

    3.2           Lost, Stolen, Mutilated or Destroyed
Warrant Certificates. Upon receipt by the Warrant Agent of evidence
reasonably satisfactory to it and the Company of the ownership of and the loss,
theft, destruction or mutilation of any Warrant Certificate and/or indemnity
reasonably satisfactory to the Warrant Agent and the Company and, in the case of
mutilation, upon surrender of the mutilated Warrant Certificate to the Warrant
Agent for cancellation, then, in the absence of notice to the Company or the
Warrant Agent that such Warrant Certificate has been acquired by a bona fide
purchaser, the Company shall execute, and an authorized officer of the Warrant
Agent shall manually countersign and deliver, in exchange for or in lieu of the
lost, stolen, destroyed or mutilated Warrant Certificate, a new Warrant
Certificate of the same tenor and evidencing Warrants for a like principal
amount of Warrant Debt Securities. Upon the issuance of any new Warrant
Certificate under this Section 3.2, the Company may require the payment of a sum
sufficient to cover any tax or other governmental charge that may be imposed in
relation thereto and any other expenses (including the fees and expenses of the
Warrant Agent) in connection therewith. Every substitute Warrant Certificate
executed and delivered pursuant to this Section 3.2 in lieu of any lost, stolen
or destroyed Warrant Certificate shall represent an additional contractual
obligation of the Company, whether or not the lost, stolen or destroyed Warrant
Certificate shall be at any time enforceable by anyone, and shall be entitled to
the benefits of this Agreement equally and proportionately with any and all
other Warrant Certificates duly executed and delivered hereunder. The provisions
of this Section 3.2 are exclusive and shall preclude (to the extent lawful) all
other rights and remedies with respect to the replacement of mutilated, lost,
stolen or destroyed Warrant Certificates.

     

    3.3           Holder Of Warrant Certificate May
Enforce Rights. Notwithstanding any of the provisions of this Agreement,
any holder of any Warrant Certificate, without the consent of the Warrant Agent,
the [Senior] [Subordinated] Trustee, the holder of any Warrant Debt Securities
or the holder of any other Warrant Certificate, may, in such holder’s own behalf
and for such holder’s own benefit, enforce, and may institute and maintain any
suit, action or proceeding against the Company suitable to enforce, or otherwise
in respect of, such holder’s right to exercise the Warrants evidenced by such
holder’s Warrant Certificate in the manner provided in such holder’s Warrant
Certificates and in this Agreement.


    
      
         


      

      
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    3.4           Merger, Sale, Conveyance or
Lease. In case of (a) any share exchange, merger or similar transaction
of the Company with or into another person or entity (other than a share
exchange, merger or similar transaction in which the Company is the acquiring or
surviving corporation) or (b) the sale, exchange, lease, transfer or other
disposition of all or substantially all of the properties and assets of the
Company as an entirety (in any such case, a “Reorganization
Event”), then, as a condition of such Reorganization Event, lawful
provisions shall be made, and duly executed documents evidencing the same from
the Company’s successor shall be delivered to the holders of the Warrants, so
that such successor shall succeed to and be substituted for the Company, and
assume all the Company’s obligations under, this Agreement and the Warrants. The
Company shall thereupon be relieved of any further obligation hereunder or under
the Warrants, and the Company as the predecessor corporation may thereupon or at
any time thereafter be dissolved, wound up or liquidated. Such successor or
assuming entity thereupon may cause to be signed, and may issue either in its
own name or in the name of the Company, any or all of the Warrants issuable
hereunder which heretofore shall not have been signed by the Company, and may
execute and deliver securities in its own name, in fulfillment of its
obligations to deliver Warrant Debt Securities upon exercise of the Warrants.
All the Warrants so issued shall in all respects have the same legal rank and
benefit under this Agreement as the Warrants theretofore or thereafter issued in
accordance with the terms of this Agreement as though all of such Warrants had
been issued at the date of the execution hereof. In any case of any such
Reorganization Event, such changes in phraseology and form (but not in
substance) may be made in the Warrants thereafter to be issued as may be
appropriate.

     

    3.5           Notice To Warrantholders. In
case the Company shall (a) effect any Reorganization Event or (b) make any
distribution on or in respect of the [title of Warrant Debt Securities] in
connection with the dissolution, liquidation or winding up of the Company, then
the Company shall mail to each holder of Warrants at such holder’s address as it
shall appear on the books of the Warrant Agent, at least ten days prior to the
applicable date hereinafter specified, a notice stating the date on which such
Reorganization Event, dissolution, liquidation or winding up is expected to
become effective, and the date as of which it is expected that holders of [title
of Warrant Debt Securities] of record shall be entitled to exchange their shares
of [title of Warrant Debt Securities] for securities or other property
deliverable upon such Reorganization Event, dissolution, liquidation or winding
up. No failure to mail such notice nor any defect therein or in the mailing
thereof shall affect any such transaction.


    
      
         


      

      
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    ARTICLE
4

     

    EXCHANGE
AND TRANSFER OF WARRANT CERTIFICATES

     

    4.1           Exchange and Transfer of Warrant
Certificates. [If Other Securities with Warrants which are immediately
detachable—Upon] [If Other Securities with Warrants which are not immediately
detachable—Prior to the Detachable Date, a Warrant Certificate may be exchanged
or transferred only together with the Other Security to which the Warrant
Certificate was initially attached, and only for the purpose of effecting or in
conjunction with an exchange or transfer of such Other Security. Prior to any
Detachable Date, each transfer of the Other Security shall operate also to
transfer the related Warrant Certificates. After the Detachable Date, upon]
surrender at the corporate trust office of the Warrant Agent, Warrant
Certificates evidencing Warrants may be exchanged for Warrant Certificates in
other denominations evidencing such Warrants or the transfer thereof may be
registered in whole or in part; provided that such other Warrant Certificates
evidence Warrants for the same aggregate principal amount of Warrant Debt
Securities as the Warrant Certificates so surrendered. The Warrant Agent shall
keep, at its corporate trust office, books in which, subject to such reasonable
regulations as it may prescribe, it shall register Warrant Certificates and
exchanges and transfers of outstanding Warrant Certificates, upon surrender of
the Warrant Certificates to the Warrant Agent at its corporate trust office for
exchange or registration of transfer, properly endorsed or accompanied by
appropriate instruments of registration of transfer and written instructions for
transfer, all in form satisfactory to the Company and the Warrant Agent. No
service charge shall be made for any exchange or registration of transfer of
Warrant Certificates, but the Company may require payment of a sum sufficient to
cover any stamp or other tax or other governmental charge that may be imposed in
connection with any such exchange or registration of transfer. Whenever any
Warrant Certificates are so surrendered for exchange or registration of
transfer, an authorized officer of the Warrant Agent shall manually countersign
and deliver to the person or persons entitled thereto a Warrant Certificate or
Warrant Certificates duly authorized and executed by the Company, as so
requested. The Warrant Agent shall not be required to effect any exchange or
registration of transfer which will result in the issuance of a Warrant
Certificate evidencing a Warrant for a fraction of a Warrant Debt Security or a
number of Warrants for a whole number of Warrant Debt Securities and a fraction
of a Warrant Debt Security. All Warrant Certificates issued upon any exchange or
registration of transfer of Warrant Certificates shall be the valid obligations
of the Company, evidencing the same obligations and entitled to the same
benefits under this Agreement as the Warrant Certificate surrendered for such
exchange or registration of transfer.

     

    4.2           Treatment of Holders of Warrant
Certificates. [If Other Securities and Warrants are not immediately
detachable—Prior to the Detachable Date, the Company, the Warrant Agent and all
other persons may treat the owner of the Other Security as the owner of the
Warrant Certificates initially attached thereto for any purpose and as the
person entitled to exercise the rights represented by the Warrants evidenced by
such Warrant Certificates, any notice to the contrary notwithstanding. After the
Detachable Date and prior to due presentment of a Warrant Certificate for
registration of transfer, the] [The] Company, the Warrant Agent and all other
persons may treat the registered holder of a Warrant Certificate as the absolute
owner thereof for any purpose and as the person entitled to exercise the rights
represented by the Warrants evidenced thereby, any notice to the contrary
notwithstanding.

     

    4.3           Cancellation of Warrant
Certificates. Any Warrant Certificate surrendered for exchange,
registration of transfer or exercise of the Warrants evidenced thereby shall, if
surrendered to the Company, be delivered to the Warrant Agent and all Warrant
Certificates surrendered or so delivered to the Warrant Agent shall be promptly
canceled by the Warrant Agent and shall not be reissued and, except as expressly
permitted by this Agreement, no Warrant Certificate shall be issued hereunder in
exchange therefor or in lieu thereof. The Warrant Agent shall deliver to the
Company from time to time or otherwise dispose of canceled Warrant Certificates
in a manner satisfactory to the Company.

     

    ARTICLE
5

     

    CONCERNING
THE WARRANT AGENT

     

    5.1           Warrant Agent. The Company
hereby appoints ___________ as Warrant Agent of the Company in respect of the
Warrants and the Warrant Certificates upon the terms and subject to the
conditions herein set forth, and ___________ hereby accepts such appointment.
The Warrant Agent shall have the powers and authority granted to and conferred
upon it in the Warrant Certificates and hereby and such further powers and
authority to act on behalf of the Company as the Company may hereafter grant to
or confer upon it. All of the terms and provisions with respect to such powers
and authority contained in the Warrant Certificates are subject to and governed
by the terms and provisions hereof.


    
      
         


      

      
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    5.2           Conditions of Warrant Agent’s
Obligations. The Warrant Agent accepts its obligations herein set forth
upon the terms and conditions hereof, including the following to all of which
the Company agrees and to all of which the rights hereunder of the holders from
time to time of the Warrant Certificates shall be subject:

     

    (a)           Compensation and
Indemnification. The Company agrees promptly to pay the Warrant Agent the
compensation to be agreed upon with the Company for all services rendered by the
Warrant Agent and to reimburse the Warrant Agent for reasonable out-of-pocket
expenses (including reasonable counsel fees) incurred without negligence, bad
faith or willful misconduct by the Warrant Agent in connection with the services
rendered hereunder by the Warrant Agent. The Company also agrees to indemnify
the Warrant Agent for, and to hold it harmless against, any loss, liability or
expense incurred without negligence, bad faith or willful misconduct on the part
of the Warrant Agent, arising out of or in connection with its acting as Warrant
Agent hereunder, including the reasonable costs and expenses of defending
against any claim of such liability.

     

    (b)           Agent for the Company. In
acting under this Warrant Agreement and in connection with the Warrant
Certificates, the Warrant Agent is acting solely as agent of the Company and
does not assume any obligations or relationship of agency or trust for or with
any of the holders of Warrant Certificates or beneficial owners of
Warrants.

     

    (c)           Counsel. The Warrant Agent may
consult with counsel satisfactory to it, which may include counsel for the
Company, and the written advice of such counsel shall be full and complete
authorization and protection in respect of any action taken, suffered or omitted
by it hereunder in good faith and in accordance with the advice of such
counsel.

     

    (d)           Documents. The Warrant Agent
shall be protected and shall incur no liability for or in respect of any action
taken or omitted by it in reliance upon any Warrant Certificate, notice,
direction, consent, certificate, affidavit, statement or other paper or document
reasonably believed by it to be genuine and to have been presented or signed by
the proper parties.

     

    (e)           Certain Transactions. The
Warrant Agent, and its officers, directors and employees, may become the owner
of, or acquire any interest in, Warrants, with the same rights that it or they
would have if it were not the Warrant Agent hereunder, and, to the extent
permitted by applicable law, it or they may engage or be interested in any
financial or other transaction with the Company and may act on, or as
depositary, trustee or agent for, any committee or body of holders of Warrant
Debt Securities or other obligations of the Company as freely as if it were not
the Warrant Agent hereunder. Nothing in this Warrant Agreement shall be deemed
to prevent the Warrant Agent from acting as [Senior] [Subordinated] Trustee
under the [Senior] [Subordinated] Indenture.


    
      
         


      

      
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    (f)           No Liability for Interest.
Unless otherwise agreed with the Company, the Warrant Agent shall have no
liability for interest on any monies at any time received by it pursuant to any
of the provisions of this Agreement or of the Warrant Certificates.

     

    (g)           No Liability for Invalidity.
The Warrant Agent shall have no liability with respect to any invalidity of this
Agreement or any of the Warrant Certificates (except as to the Warrant Agent’s
countersignature thereon).

     

    (h)           No Responsibility for
Representations. The Warrant Agent shall not be responsible for any of
the recitals or representations herein or in the Warrant Certificates (except as
to the Warrant Agent’s countersignature thereon), all of which are made solely
by the Company.

     

    (i)           No Implied Obligations. The
Warrant Agent shall be obligated to perform only such duties as are herein and
in the Warrant Certificates specifically set forth and no implied duties or
obligations shall be read into this Agreement or the Warrant Certificates
against the Warrant Agent. The Warrant Agent shall not be under any obligation
to take any action hereunder which may tend to involve it in any expense or
liability, the payment of which within a reasonable time is not, in its
reasonable opinion, assured to it. The Warrant Agent shall not be accountable or
under any duty or responsibility for the use by the Company of any of the
Warrant Certificates authenticated by the Warrant Agent and delivered by it to
the Company pursuant to this Agreement or for the application by the Company of
the proceeds of the Warrant Certificates. The Warrant Agent shall have no duty
or responsibility in case of any default by the Company in the performance of
its covenants or agreements contained herein or in the Warrant Certificates or
in the case of the receipt of any written demand from a holder of a Warrant
Certificate with respect to such default, including, without limiting the
generality of the foregoing, any duty or responsibility to initiate or attempt
to initiate any proceedings at law or otherwise or, except as provided in
Section 6.2 hereof, to make any demand upon the Company.

     

    5.3           Resignation
, Removal and Appointment of Successors.

     

    (a)           The
Company agrees, for the benefit of the holders from time to time of the Warrant
Certificates, that there shall at all times be a Warrant Agent hereunder until
all the Warrants have been exercised or are no longer exercisable.

     

    (b)           The
Warrant Agent may at any time resign as agent by giving written notice to the
Company of such intention on its part, specifying the date on which its desired
resignation shall become effective; provided that such date shall not be less
than three months after the date on which such notice is given unless the
Company otherwise agrees. The Warrant Agent hereunder may be removed at any time
by the filing with it of an instrument in writing signed by or on behalf of the
Company and specifying such removal and the intended date when it shall become
effective. Such resignation or removal shall take effect upon the appointment by
the Company, as hereinafter provided, of a successor Warrant Agent (which shall
be a bank or trust company authorized under the laws of the jurisdiction of its
organization to exercise corporate trust powers) and the acceptance of such
appointment by such successor Warrant Agent. The obligation of the Company under
Section 5.2(a) shall continue to the extent set forth therein notwithstanding
the resignation or removal of the Warrant Agent.


    
      
         


      

      
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    (c)           In
case at any time the Warrant Agent shall resign, or shall be removed, or shall
become incapable of acting, or shall be adjudged a bankrupt or insolvent, or
shall commence a voluntary case under the Federal bankruptcy laws, as now or
hereafter constituted, or under any other applicable Federal or state
bankruptcy, insolvency or similar law or shall consent to the appointment of or
taking possession by a receiver, custodian, liquidator, assignee, trustee,
sequestrator (or other similar official) of the Warrant Agent or its property or
affairs, or shall make an assignment for the benefit of creditors, or shall
admit in writing its inability to pay its debts generally as they become due, or
shall take corporate action in furtherance of any such action, or a decree or
order for relief by a court having jurisdiction in the premises shall have been
entered in respect of the Warrant Agent in an involuntary case under the Federal
bankruptcy laws, as now or hereafter constituted, or any other applicable
Federal or state bankruptcy, insolvency or similar law, or a decree or order by
a court having jurisdiction in the premises shall have been entered for the
appointment of a receiver, custodian, liquidator, assignee, trustee,
sequestrator (or similar official) of the Warrant Agent or of its property or
affairs, or any public officer shall take charge or control of the Warrant Agent
or of its property or affairs for the purpose of rehabilitation, conservation,
winding up or liquidation, a successor Warrant Agent, qualified as aforesaid,
shall be appointed by the Company by an instrument in writing, filed with the
successor Warrant Agent. Upon the appointment as aforesaid of a successor
Warrant Agent and acceptance by the successor Warrant Agent of such appointment,
the Warrant Agent shall cease to be Warrant Agent hereunder.

     

    (d)           Any
successor Warrant Agent appointed hereunder shall execute, acknowledge and
deliver to its predecessor and to the Company an instrument accepting such
appointment hereunder, and thereupon such successor Warrant Agent, without any
further act, deed or conveyance, shall become vested with all the authority,
rights, powers, trusts, immunities, duties and obligations of such predecessor
with like effect as if originally named as Warrant Agent hereunder, and such
predecessor, upon payment of its charges and disbursements then unpaid, shall
thereupon become obligated to transfer, deliver and pay over, and such successor
Warrant Agent shall be entitled to receive, all monies, securities and other
property on deposit with or held by such predecessor, as Warrant Agent
hereunder.

     

    (e)           Any
corporation into which the Warrant Agent hereunder may be merged or converted or
any corporation with which the Warrant Agent may be consolidated, or any
corporation resulting from any merger, conversion or consolidation to which the
Warrant Agent shall be a party, or any corporation to which the Warrant Agent
shall sell or otherwise transfer all or substantially all the assets and
business of the Warrant Agent, provided that it shall be qualified as aforesaid,
shall be the successor Warrant Agent under this Agreement without the execution
or filing of any paper or any further act on the part of any of the parties
hereto.

     

    ARTICLE
6

     

    MISCELLANEOUS

     

    6.1           Amendment. This Agreement may
be amended by the parties hereto, without the consent of the holder of any
Warrant Certificate, for the purpose of curing any ambiguity, or of curing,
correcting or supplementing any defective provision contained herein, or making
any other provisions with respect to matters or questions arising under this
Agreement as the Company and the Warrant Agent may deem necessary or desirable;
provided that such action shall not materially adversely affect the interests of
the holders of the Warrant Certificates.


    
      
         


      

      
        11

        
          

        

      

      
         


      

    


    6.2           Notices and Demands to the Company
and Warrant Agent. If the Warrant Agent shall receive any notice or
demand addressed to the Company by the holder of a Warrant Certificate pursuant
to the provisions of the Warrant Certificates, the Warrant Agent shall promptly
forward such notice or demand to the Company.

     

    6.3           Addresses. Any communication
from the Company to the Warrant Agent with respect to this Agreement shall be
addressed to                     ,
Attention:                      
and any communication from the Warrant Agent to the Company with respect to this
Agreement shall be addressed to Micromet, Inc., 6707 Democracy Blvd., Suite
505, Bethesda, Maryland, 20817, Attention: General Counsel (or such other
address as shall be specified in writing by the Warrant Agent or by the
Company).

     

    6.4           Governing Law. This Agreement
and each Warrant Certificate issued hereunder shall be governed by and construed
in accordance with the laws of the State of New York.

     

    6.5           Delivery Of Prospectus. The
Company shall furnish to the Warrant Agent sufficient copies of a prospectus
meeting the requirements of the Securities Act of 1933, as amended, relating to
the Warrant Debt Securities deliverable upon exercise of the Warrants (the
“Prospectus”),
and the Warrant Agent agrees that upon the exercise of any Warrant, the Warrant
Agent will deliver to the holder of the Warrant Certificate evidencing such
Warrant, prior to or concurrently with the delivery of the Warrant Debt
Securities issued upon such exercise, a Prospectus. The Warrant Agent shall not,
by reason of any such delivery, assume any responsibility for the accuracy or
adequacy of such Prospectus.

     

    6.6           Obtaining of Governmental
Approvals. The Company will from time to time take all action which may
be necessary to obtain and keep effective any and all permits, consents and
approvals of governmental agencies and authorities and securities act filings
under United States Federal and state laws (including without limitation a
registration statement in respect of the Warrants and Warrant Debt Securities
under the Securities Act of 1933, as amended), which may be or become requisite
in connection with the issuance, sale, transfer, and delivery of the Warrant
Debt Securities issued upon exercise of the Warrants, the issuance, sale,
transfer and delivery of the Warrants or upon the expiration of the period
during which the Warrants are exercisable.

     

    6.7           Persons Having Rights Under Warrant
Agreement. Nothing in this Agreement shall give to any person other than
the Company, the Warrant Agent and the holders of the Warrant Certificates any
right, remedy or claim under or by reason of this Agreement.

     

    6.8           Headings. The descriptive
headings of the several Articles and Sections of this Agreement are inserted for
convenience only and shall not control or affect the meaning or construction of
any of the provisions hereof.

     

    6.9           Counterparts. This Agreement
may be executed in any number of counterparts, each of which as so executed
shall be deemed to be an original, but such counterparts shall together
constitute but one and the same instrument.


    
      
         


      

      
        12

        
          

        

      

      
         


      

    


    6.10        Inspection of Agreement. A
copy of this Agreement shall be available at all reasonable times at the
principal corporate trust office of the Warrant Agent for inspection by the
holder of any Warrant Certificate. The Warrant Agent may require such holder to
submit his Warrant Certificate for inspection by it.


    
      
         


      

      
        13

        
          

        

      

      
         


      

    


    In Witness
Whereof, the parties hereto have caused this Agreement to be duly
executed, all as of the day and year first above written.

     

    
      
        	 
      	
                Micromet,
      Inc.

              
	 
      	 
      	 
      
	 
      	
                By:

              	 
      
	 
      	 
      	 
      
	 
      	
                Name:

              	 
      
	 
      	 
      	 
      
	 
      	
                Title:

              	 
      
	 
      	 
      
	 
      	
                [Warrant
      Agent], as Warrant Agent

              
	 
      	 
      	 
      
	 
      	
                By:

              	 
      
	 
      	 
      	 
      
	 
      	
                Name:

              	 
      
	 
      	 
      	 
      
	 
      	
                Title:

              	 
      


      

    

     

    [SIGNATURE
PAGE TO DEBT SECURITIES WARRANT AGREEMENT]


    
      
         


      

      
        14

        
          

        

      

      
         


      

    


    EXHIBIT
A

     

    FORM
OF WARRANT CERTIFICATE

    [FACE
OF WARRANT CERTIFICATE]

     

    
      
        
          
            	
                    [[Form
      if Warrants are attached to Other Securities and are not immediately
      detachable.]

                  	 
      	
                    [Prior
      to
      _________, this Warrant Certificate cannot be transferred or
      exchanged unless attached to a [Title of Other
    Securities].]

                  
	 
      	 
      	 
      
	
                    [Form
      of Legend if Warrants are not immediately exercisable.]

                  	 
      	
                    [Prior
      to _________, Warrants evidenced by this Warrant Certificate cannot be
      exercised.]

                  


          

        

      

    

     

    EXERCISABLE
ONLY IF COUNTERSIGNED BY THE WARRANT AGENT AS PROVIDED HEREIN

     

    VOID
AFTER [        ]
P.M., [___________] TIME, ON                     ,


    
      
         


      

      
        15

        
          

        

      

      
         


      

    


    MICROMET, INC.

    WARRANT
CERTIFICATE REPRESENTING

    WARRANTS
TO PURCHASE

    [TITLE
OF WARRANT DEBT SECURITIES]

     

    
      
        
          
            
              
                
                  	
                          No.

                        	 
      	 
      	
                          Warrants

                        


                

              

            

          

        

      

    

     

    This
certifies that                                
or registered assigns is the registered owner of the above indicated number of
Warrants, each Warrant entitling such owner [If Warrants are attached to Other
Securities and are not immediately detachable —, subject to the registered owner
qualifying as a “Holder” of this Warrant Certificate, as hereinafter defined)]
to purchase, at any time [after [          ]
p.m., [City] time, on                                
and] on or before [        ]
p.m., [City] time, on                                ,
$       
principal amount of [Title of Warrant Debt Securities] (the “Warrant Debt
Securities”), of Micromet, Inc. (the “Company”),
issued or to be issued under the Indenture (as hereinafter defined), on the
following basis: during the period from                                ,
through and including                                ,
each Warrant shall entitle the Holder thereof, subject to the provisions of this
Agreement, to purchase the principal amount of Warrant Debt Securities stated in
the Warrant Certificate at the warrant price (the “Warrant
Price”) of        %
of the principal amount thereof [plus accrued amortization, if any, of the
original issue discount of the Warrant Debt Securities] [plus accrued interest,
if any, from the most recent date from which interest shall have been paid on
the Warrant Debt Securities or, if no interest shall have been paid on the
Warrant Debt Securities, from the date of their original issuance]. [The
original issue discount ($         
for each $1,000 principal amount of Warrant Debt Securities) will be amortized
at a           %
annual rate, computed on a[n] [semi-]annual basis [using a 360-day year
consisting of twelve 30-day months]. The Holder may exercise the Warrants
evidenced hereby by providing certain information set forth on the back hereof
and by paying in full, in lawful money of the United States of America, [in cash
or by certified check or official bank check in New York Clearing House funds]
[by bank wire transfer in immediately available funds], the Warrant Price for
each Warrant Debt Security with respect to which this Warrant is exercised to
the Warrant Agent (as hereinafter defined) and by surrendering this Warrant
Certificate, with the purchase form on the back hereof duly executed, at the
corporate trust office of [name of Warrant Agent], or its successor as warrant
agent (the “Warrant
Agent”), which is, on the date hereof, at the address specified on the
reverse hereof, and upon compliance with and subject to the conditions set forth
herein and in the Warrant Agreement (as hereinafter defined).

     

    The term
“Holder” as used herein shall mean [If Warrants are attached to Other Securities
and are not immediately detachable—, prior to                            ,
           
(the “Detachable
Date”), the registered owner of the Company’s [title of Other Securities]
to which this Warrant Certificate was initially attached, and after such
Detachable Date,] the person in whose name at the time this Warrant Certificate
shall be registered upon the books to be maintained by the Warrant Agent for
that purpose pursuant to Section 4 of the Warrant Agreement.

     

    The
Warrants evidenced by this Warrant Certificate may be exercised to purchase
Warrant Debt Securities in the principal amount of $1,000 or any integral
multiple thereof in registered form. Upon any exercise of fewer than all of the
Warrants evidenced by this Warrant Certificate, there shall be issued to the
Holder hereof a new Warrant Certificate evidencing Warrants for the aggregate
principal amount of Warrant Debt Securities remaining
unexercised.


    
      
         


      

      
        16

        
          

        

      

      
         


      

    


    This
Warrant Certificate is issued under and in accordance with the Warrant Agreement
dated as of                        ,
         
(the “Warrant
Agreement”), between the Company and the Warrant Agent and is subject to
the terms and provisions contained in the Warrant Agreement, to all of which
terms and provisions the Holder of this Warrant Certificate consents by
acceptance hereof. Copies of the Warrant Agreement are on file at the
above-mentioned office of the Warrant Agent.

     

    The
Warrant Debt Securities to be issued and delivered upon the exercise of Warrants
evidenced by this Warrant Certificate will be issued under and in accordance
with an Indenture, [dated as of                      ,
             
(the “Senior
Indenture”), between the Company and                                 ,
as trustee (such trustee, and any successors to such trustee, the “Senior
Trustee”)] [dated as of                                ,
                               ,
(the “Subordinated
Indenture”), between the Company and                                ,
as trustee (such trustee, and any successors to such trustee, the “Subordinated
Trustee”)] and will be subject to the terms and provisions contained in
the Warrant Debt Securities and in the Indenture. Copies of the [Senior]
[Subordinated] Indenture, including the form of the Warrant Debt Securities, are
on file at the corporate trust office of the Trustee.

     

    [If
Warrants are attached to Other Securities and are not immediately
detachable—Prior to the Detachable Date, this Warrant Certificate may be
exchanged or transferred only together with the [Title of Other Securities] (the
“Other
Securities”) to which this Warrant Certificate was initially attached,
and only for the purpose of effecting or in conjunction with, an exchange or
transfer of such Other Security. Additionally, on or prior to the Detachable
Date, each transfer of such Other Security on the register of the Other
Securities shall operate also to transfer this Warrant Certificate. After such
date, transfer of this] [If Warrants are attached to Other Securities and are
immediately detachable—Transfer of this] Warrant Certificate may be registered
when this Warrant Certificate is surrendered at the corporate trust office of
the Warrant Agent by the registered owner or such owner’s assigns, in the manner
and subject to the limitations provided in the Warrant Agreement.

     

    [If Other
Securities with Warrants which are not immediately detachable-Except as provided
in the immediately preceding paragraph, after] [If Other Securities with
Warrants which are immediately detachable or Warrants alone—After]
countersignature by the Warrant Agent and prior to the expiration of this
Warrant Certificate, this Warrant Certificate may be exchanged at the corporate
trust office of the Warrant Agent for Warrant Certificates representing Warrants
for the same aggregate principal amount of Warrant Debt Securities.

     

    This
Warrant Certificate shall not entitle the Holder hereof to any of the rights of
a holder of the Warrant Debt Securities, including, without limitation, the
right to receive payments of principal of (and premium, if any) or interest, if
any, on the Warrant Debt Securities or to enforce any of the covenants of the
Indenture.

     

    Reference
is hereby made to the further provisions of this Warrant Certificate set forth
on the reverse hereof, which further provisions shall for all purposes have the
same effect as if set forth at this place.


    This
Warrant Certificate shall not be valid or obligatory for any purpose until
countersigned by the Warrant Agent.


    
      
         


      

      
        17

        
          

        

      

      
         


      

    


    In Witness
Whereof, the Company has caused this Warrant to be executed in its name
and on its behalf by the facsimile signatures of its duly authorized
officers.

     

    
      
        	
                Dated:

              	 
      	 
      


      

    

    


    
      
        	 
      	
                Micromet,
      Inc.

              
	 
      	 
      	 
      
	 
      	
                By:

              	 
      
	 
      	 
      	 
      
	 
      	
                Name:

              	 
      
	 
      	 
      	 
      
	 
      	
                Title:

              	 
      


      

    

    


    
      
        	 
      	
                Countersigned:

              


      

    

    


    
      
        	 
      	
                [Warrant
      Agent], as Warrant Agent

              
	 
      	 
      	 
      
	 
      	
                By:

              	 
      
	 
      	 
      	 
      
	 
      	
                Name:

              	 
      
	 
      	 
      	 
      
	 
      	
                Title:

              	 
      


      

    


    
      
         


      

      
        18

        
          

        

      

      
         


      

    


    [REVERSE
OF WARRANT CERTIFICATE]

     

    (Instructions
for Exercise of Warrant)

     

    To
exercise any Warrants evidenced hereby for Warrant Debt Securities (as
hereinafter defined), the Holder must pay, in lawful money of the United States
of America, [in cash or by certified check or official bank check in New York
Clearing House funds] [by bank wire transfer in immediately available funds],
the Warrant Price in full for Warrants exercised, to [Warrant Agent] [address of
Warrant Agent], Attn:                         ,
which payment must specify the name of the Holder and the number of Warrants
exercised by such Holder. In addition, the Holder must complete the information
required below and present this Warrant Certificate in person or by mail
(certified or registered mail is recommended) to the Warrant Agent at the
appropriate address set forth above. This Warrant Certificate, completed and
duly executed, must be received by the Warrant Agent within five business days
of the payment.

     

    (To be
executed upon exercise of Warrants)

     

    The
undersigned hereby irrevocably elects to exercise                   
Warrants, represented by this Warrant Certificate, to purchase $           
principal amount of the [Title of Warrant Debt Securities] (the “Warrant Debt
Securities”) of Micromet, Inc. and represents that he has tendered
payment for such Warrant Debt Securities, in lawful money of the United States
of America, [in cash or by certified check or official bank check in New York
Clearing House funds] [by bank wire transfer in immediately available funds], to
the order of Micromet, Inc., c/o [insert name and address of Warrant
Agent], in the amount of $            
in accordance with the terms hereof. The undersigned requests that said
principal amount of Warrant Debt Securities be in fully registered form in the
authorized denominations, registered in such names and delivered all as
specified in accordance with the instructions set forth below.

     

    If the
number of Warrants exercised is less than all the Warrants evidenced hereby, the
undersigned requests that a new Warrant Certificate evidencing the Warrants for
the aggregate principal amount of Warrant Debt Securities remaining unexercised
be issued and delivered to the undersigned unless otherwise specified in the
instructions below.

     

    
      
        
          	
                  Dated

                	 
      	 
      	
                  Name

                	 
      
	 
      	 
      	 
      	 
      	
                  Please
      Print

                


        

      

    

     

    
      
        
          
            
              
                	
                        Address:

                      	 
      	 
      
	 
      	 
      	 
      
	 	 	 


              

            

          

        

      

    

    


    
      
        
          
            
              
                
                  
                    	 
      	 
      
	
                            (Insert
      Social Security or Other Identifying Number of Holder)

                          	 
      


                  

                

              

            

          

        

      

    

    


    
      
        	
                Signature
      Guaranteed

              	 
      	 
      
	 
      	
                Signature

              	 
      


      

    

     

    
      
         


      

      
        19

        
          

        

      

      
         


      

    


    (Signature
must conform in all respects to name of holder as specified on the face of this
Warrant Certificate and must bear a signature guarantee by a bank, trust company
or member broker of the New York, Midwest or Pacific Stock
Exchange).

     

    This
Warrant may be exercised at the following addresses:

     

    
      
        
          
            
              	
                      By
      hand at

                    	 
      	 
      
	 
      	 
      	 
      
	 
      	 
      	 
      
	 
      	 
      	 
      
	 
      	 
      	 
      
	 
      	 
      	 
      
	
                      By
      mail at

                    	 
      	 
      
	 
      	 
      	 
      
	 
      	 
      	 
      
	 
      	 
      	 
      
	 
      	 
      	 
      


            

          

        

      

    

     

    [Instructions
as to form and delivery of Warrant Debt Securities and, if applicable, Warrant
Certificates evidencing Warrants for the number of Warrant Debt Securities
remaining unexercised—complete as appropriate.]


    
      
         


      

      
        20

        
          

        

      

      
         


      

    


    ASSIGNMENT

     

    [Form of
assignment to be executed if Warrant Holder desires to transfer
Warrant]

     

    FOR VALUE
RECEIVED,                     
hereby sells, assigns and transfers unto:

     

    
      
        
          	 
      	 
      	 
      
	 
      	 
      	 
      
	 
      	 
      	 
      
	 
      	 
      	 
      
	 
      	 
      	 
      
	
                  (Please
      print name and address including zip code)

                	 
      	
                  Please
      print Social Security or other identifying
  number

                


        

      

    

     

    the right
represented by the within Warrant to purchase $           
aggregate principal amount of [Title of Warrant Debt Securities] of
Micromet, Inc. to which the within Warrant relates and appoints                     
attorney to transfer such right on the books of the Warrant Agent with full
power of substitution in the premises.

     

    
      
        	
                Dated

              	 
      	 
      	 
      
	 
      	 
      	
                Signature

              


      

    

    (Signature
must conform in all respects to name of holder as specified on the face of the
Warrant)

     

    
      
        	
                Signature
      Guaranteed

              	 
      
	 
      	 
      
	 
      	 
      


      

    

     

    
      
         


      

      
        21