<PAGE>
                                                                    Exhibit 4.15

                                                              2005 SERIES B NOTE

IF AND TO THE EXTENT THAT THIS NOTE CONSTITUTES A SECURITY, THE SECURITIES
REPRESENTED BY THIS INSTRUMENT HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT
OF 1933, AS AMENDED, OR QUALIFIED UNDER APPLICABLE STATE SECURITIES LAWS AND
HAVE BEEN TAKEN FOR INVESTMENT PURPOSES ONLY AND NOT WITH A VIEW TO OR FOR SALE
IN CONNECTION WITH ANY DISTRIBUTION THEREOF. IF AND TO THE EXTENT THAT THIS NOTE
CONSTITUTES A SECURITY, THE SECURITIES MAY NOT BE SOLD OR OTHERWISE TRANSFERRED
IN THE ABSENCE OF SUCH REGISTRATION AND QUALIFICATION WITHOUT AN OPINION OF
COUNSEL FOR THE HOLDER THAT SUCH REGISTRATION AND QUALIFICATION ARE NOT
REQUIRED.

             AMENDED AND RESTATED SENIOR CONVERTIBLE PROMISSORY NOTE

                                                              New York, New York
$154,555                                                        January 29, 2005

     1.   Principal and Interest.

Omrix Biopharmaceuticals, Inc. (the "Company"), a Delaware corporation, for
value received, hereby promises indefeasibly to pay to the order of Philippe
Romagnoli or holder (the "Holder") in lawful money of the United States at the
address of the Holder set forth below or such other address as the Holder may
specify by written notice, the principal amount of One Hundred Fifty-Four
Thousand Five Hundred Fifty Five Dollars exactly ($154,555), together with
interest at ten percent (10%) per annum, compounded annually, until the maturity
of this Note, whether as scheduled or by acceleration or otherwise, and,
thereafter, at the lesser of (i) fifteen percent (15%) per annum, and (ii) the
maximum legal rate of interest that may be charged at any time on such debt. All
computations of interest shall be made on the basis of a 365-day year for actual
days elapsed.

          (a) This Note is one of two series of notes constituting senior
unsecured obligations of the company being issued by the Company to the Holder
and certain other holders (collectively with the Holder, the "Aggregate
Holders") in the aggregate principal amount of $1,966,950. The first series of
notes (which consist of a sole Note) in the aggregate principal amount of
$752,148 (the "2005 Series A Note") is being issued by the Company to the Holder
as an amendment and restatement of that certain note issued by the Company on
September 20, 2002 in the face amount of $500,000 (the "2002 Senior Note") to
the Holder. The second series of notes (which this note is part of) in the
aggregate principal amount $1,214,802 (the "2005 Series B Notes") is being
issued to the Aggregate Holders as an amendment and restatement of those certain
notes issued by the Company on September 20, 2002 in the aggregate face amount
of $982,500 (the "2002 Senior Notes") to the Aggregate Holders. The Holder, as
holder of the 2002 Senior Note, agrees that (i) such amendment and restatement
is in lieu of, and by its acceptance of this Note agrees to forego, any and all
interest to which such holder was entitled under terms of the 2002 Senior Note
and to forgo any conversion right or privilege to which the Holder was or could
have been entitled under the terms of the 2002 Senior Note, and (ii) the
security interest granted by the company to secure the 2001 Senior Notes and the
2002 Senior Notes has been terminated.

<PAGE>

          (b) The principal of and accrued interest on this Note shall be due
and payable on the earlier to occur of (i) December 30, 2007 (the "Stated
Maturity Date"), or (ii) acceleration of this Note following an Event of Default
(as defined below). The Company may prepay this Note at any time, in whole or in
part, at 100% of the principal amount so prepaid, together with a Prepayment
Premium as defined below plus accrued interest at the date of prepayment. The
Holder of this Note may demand the repayment of this Note, together with a
Prepayment Premium plus accrued interest at the date of prepayment, upon the
occurrence of a Change in Control. As used in this Note, "Change of Control"
means (y) the consummation of any transaction or series of related transactions
that results in the holders of record of the Company's capital stock immediately
prior to the transaction or transactions holding less than fifty percent (50%)
of the voting power of the Company immediately after the transaction or
transactions, including the acquisition of the Company by another entity and any
reorganization, merger, consolidation or share exchange, or which results in the
sale of all or substantially all of the assets of the Company or (z) the
consummation of an underwritten public offering of the Company's capital stock
(an "IPO"). "Change of Control" does not include a financing in which the
Company issues shares of its capital stock (or securities convertible into or
exercisable for shares of any of its capital stock) and existing investors of
the Company, including the Company's note holders retain 50% ownership or more
of the Company on an as converted fully diluted basis. For purposes of the
subsection (c), if the consideration payable to the Company or its stockholders
in connection with a Change of Control shall consist, in whole or in part, of
securities or other property other than cash, the payment required by this
subsection in connection with such Change of Control may, at the option of the
Company, be made to the Holder in the form of such securities or other property,
valued at the same value attributed to such securities or other property in
connection with the Change of Control transaction.

Prepayment Premium - The multiple of the face amount as set forth in the
following table with respect to the time of prepayment of this note:

<TABLE>
<CAPTION>
     Time of Prepayment (no. of         Prepayment Premium in
     months following issuance)        Multiple of Face Amount
     --------------------------        -----------------------
<S>                                    <C>
           up to 12 months                       2.0x
more than 12 months, up to 24 months             1.0x
more than 24 months, up to 36 months              .5x
</TABLE>

          (c) The Company shall deliver to the Holder a notice at least 20 days
prior to any Change of Control describing in reasonable detail all material
terms of such Change of Control.

<PAGE>

          (d) Upon payment in full or conversion in accordance with this Note of
all principal, interest and other amounts payable in connection with the Note,
the Note shall be surrendered to the Company for cancellation.

          (e) The Company shall make all payments due hereunder at the Holder's
address set forth on the books and records of the Company, or such other place
as the Holder may designate by written notice to the Company. Each payment shall
be applied to such indebtedness as Holder may direct in its discretion.

          (f) All payments under this Note shall be made unconditionally,
indefeasibly and in full without deduction, setoff, recoupment, counterclaim, or
other defense, all of which are hereby waived to the maximum extent permitted by
applicable law. If the Company or any of its affiliates have any claim,
recoupment, setoff, defense or other right to the contrary, the Company shall
notify Holder in writing immediately, and the Company represents and warrants
that it presently has no such claims, recoupments, setoffs, defenses or other
such rights.

          (g) The Company also waives presentment, protest, presentation of the
Note and any other condition precedent to payment to the Holder.

          (h) The Company shall pay all amounts due free and clear of and
without reduction or deduction for or on account of any present or future taxes,
levies, charges, imports, duties, assessments, withholding or other governmental
obligations, exclusive of any taxes based upon the income of the Holder
(collectively called "Taxes"), and the Company shall increase such amounts paid
to the Holder as needed in order to satisfy its obligations to Holder net of any
Taxes. The Company shall indemnify Holder against and hold Holder harmless from
any Taxes or any obligation of Holder to withhold or turn over any amount for or
on account of any Taxes and any right of any holder of any indebtedness which is
not asserted by written notice to the Holder, and on account of any costs or
liabilities associated therewith. By its acceptance of this Note, Holder
covenants and agrees with the Company that it will report or declare any Taxes
paid by the Company on behalf of the Holder pursuant to this subsection (i) as
having been paid by the Holder and will use any credit or deduction in respect
of such Tax payment to reduce or offset its liability for Taxes in the
jurisdiction in which it is a resident or domiciliary for Tax purposes, and will
pay over to the Company any resulting net Tax savings attributable to such
payment of Taxes by the Company.

     2.   Event of Default and Acceleration.

          (a) The occurrence of any of the following shall constitute an "Event
of Default" hereunder:

               (i) The Company shall fail to observe or perform any covenant or
agreement of the Company set forth in this Note.

               (ii) Any representation or warranty made by or on behalf of the
Company in this Note or in any instrument or document furnished to Holder in
connection herewith shall prove to be false or misleading in any material
respect as of the most recent date such representation or warranty was made,
except to the extent any such representation or warranty expressly relates to an
earlier date.

<PAGE>

               (iii) The Company or any of its subsidiaries at any time shall be
in default (as principal or guarantor or other surety) in the payment of any
principal of or premium or interest on any indebtedness for borrowed money in
excess of $200,000 beyond the grace period, if any, applicable thereto, except
any such default (A) as is being contested in good faith (and, if necessary, by
appropriate proceedings) by the Company or the relevant subsidiary, provided
that if required by generally accepted accounting principles the Company or such
subsidiary shall have set aside on its books a sufficient reserve with respect
to such indebtedness, or (B) where the failure to pay such indebtedness when due
and any such related default would not have a material adverse effect on the
business, properties, assets or condition (financial or otherwise) of the
Company and its subsidiaries.

               (iv) The Company or any of its subsidiaries shall (A) generally
not be paying its debts as they become due, (B) file, or consent, by answer or
otherwise, to the filing against it of a petition for relief or reorganization
or arrangement or any other petition in bankruptcy or insolvency under the laws
of any jurisdiction, (C) make an assignment for the benefit of creditors, (D)
consent to the appointment of a custodian, receiver, trustee or other officer
with similar powers for it or for any substantial part of its property, or (E)
be adjudicated insolvent.

               (v) Any court of competent jurisdiction shall enter an order
appointing, without consent of the Company or any of its subsidiaries, a
custodian, receiver, trustee or other officer with similar powers with respect
to it or with respect to any substantial part of its property, or if an order
for relief shall be entered in any case or proceeding for liquidation or
reorganization or otherwise to take advantage of any bankruptcy or insolvency
law of any jurisdiction, or ordering the dissolution, winding-up or liquidation
of the Company or any of its subsidiaries or any petition for any such relief
shall be filed against it and such petition shall not be dismissed or stayed
within 60 days.

               (vi) There shall be entered against the Company or any of its
subsidiaries one or more judgments, awards or decrees, or orders of attachment,
garnishment or any other writ, which exceed $200,000 (including the amount of
any self-retention and standard deductibles with respect to any of the foregoing
otherwise covered by insurance) in the aggregate at any one time outstanding,
excluding judgments, awards, decrees, orders or writs (A) for which there is
full insurance (subject to self-retention and standard deductibles) and with
respect to which the insurer has assumed responsibility in writing, (B) for
which there is full indemnification (upon terms and by creditworthy indemnitors
which are reasonably satisfactory to the Holder of this Note) or (C) which have
been in force for less than the applicable period for filing an appeal so long
as execution has not been levied thereunder or in respect of which the Company
or any of its subsidiaries shall at the time in good faith be prosecuting an
appeal or proceeding for review and in respect of which a stay of execution or
appropriate appeal bond shall have been obtained pending such appeal or review.

               (vii) If the Company shall deny or disaffirm its obligations
hereunder or fail to make any payment required hereunder when due.

<PAGE>

          (b) Acceleration.

               (i) If an Event of Default occurs and is continuing, the Holder
may declare the principal amount of this Note, and all accrued and unpaid
interest thereon, to be due and payable immediately and, upon such declaration,
the Company shall be immediately obligated to pay to the Holder cash in an
amount equal to the outstanding principal amount of this Note plus accrued and
unpaid interest through the date payment is received by the Holder.

               (ii) Notwithstanding anything to the contrary in this Note, if an
Event of Default arises under subsections (a)(iv) and (a)(v) of this Section 2,
the entire principal amount of this Note plus accrued and unpaid interest
thereon shall automatically become due and payable in full without the necessity
for any declaration or other act on the part of the Holder and the Company shall
be immediately obligated to pay to the Holder cash in an amount equal to the
outstanding principal amount plus accrued and unpaid interest through the date
payment is received by the Holder.

               (iii) If an Event of Default occurs and is continuing, the Holder
may pursue any available remedy to collect the payment of principal of or
interest on this Note or to enforce the performance of any provision of this
Note. A delay or omission by the Holder in exercising any right or remedy
accruing upon an Event of Default shall not impair the right or remedy or
constitute a waiver of or acquiescence in the Event of Default. All remedies are
cumulative to the extent permitted by law.

     3. Restriction on Debt. Without the written consent of the holders of a
majority in aggregate principal amount of the 2005 Series A Note and the 2005
Series B Notes acting as a single series of Notes, the Company will not, after
November 30, 2004, incur, assume, guarantee or become liable, with respect for
any indebtedness for borrowed money senior to this Note and owed to banks or
other financial institutions in an aggregate principal amount excess of
$5,000,000 ("Additional Financial Debt"). The preceding shall not preclude or
prohibit amendment, renewals, modifications or refundings of any indebtedness,
including Additional Financial Debt, in connection with a refinancing thereof,
provided that the aggregate amount of such indebtedness for borrowed money is
not increased beyond principal amount thereof at the time of such amendment,
renewal, modification or refunding. By its receipt and acceptance of this Note,
the Holder agrees that such consent will not be unreasonably withheld. The
Company and the Holder, by its acceptance of this Note, acknowledge and agree
that the obligations of the Company under this Note are equal in priority to the
obligations of the Company under the 2005 Series A Note. For the avoidance of
doubt the Company agrees that the 2005 Series A Note and the 2005 Series B Notes
will not be made junior to any additional indebtedness of the Company for
borrowed money, other than the then permitted Additional Financial Debt, without
the written consent of the holders of a majority in aggregate principal amount
of the 2005 Series A Note and the 2005 Series B Notes acting as a single series
of Notes.

     4. Representations and Warranties. The Company hereby represents and
warrants to the Holder as follows: (a) the Company is a corporation duly
incorporated, validly existing and in good standing under the laws of the State
of Delaware, with full corporate power and authority to enter into and perform
its obligations under this Note; and (b) the execution and delivery of this Note
by the Company, and performance of the Company's obligations hereunder, have
been

<PAGE>

duly and validly authorized by all necessary corporate action (provided,
however, that the issuance of the securities to be issued upon conversion of
this Note may require additional action by the Company's directors and
stockholders (including such action as may be required to authorize any
"Financing (as described in Section 5, below) as a result of which this Note
will become convertible) and an applicable and valid filing with the Secretary
of State of Delaware) and, upon such issuance (and such additional director
action and such filing with the Secretary of State of Delaware), such securities
will be validly issued, fully paid, and nonassessable.

          Information rights. The holders of a majority in aggregate principal
amount of the 2005 Series A Note and the 2005 Series B Notes acting as a single
series of Notes, will appoint a representative holder to which the company will
submit it's quarterly and year end financial statements, together with a report
on the status of the Additional Financial Debt as of the date of such report

     5. Conversion.

          (a) Optional Conversion. At the sole election of the Holder and
without creating any subordination or any rights whatsoever in favor of any
holder of any other indebtedness or any other person, all or any part of the
outstanding principal balance of this Note and all or any part of the interest
accrued and unpaid thereon and other amounts owing hereunder may be converted at
any time after notice by the Holder upon the closing (evidenced by the execution
of a purchase agreement or similar commitment of the Company to issue its
securities) of the Next Financing (as defined below) by the Company into the
securities (the "Securities") issued in the Next Financing at a conversion price
equal to the lower of (i) eighty percent (80%) of the purchase price paid for
the Securities by the investors in the Next Financing and (ii) $2.25 per
Security, and with the same rights, preferences, privileges and restrictions as
the Securities issued in the Next Financing. A "Next Financing" is the issuance
by the Company, in a single transaction or series of related transactions after
the date of this Note, of shares of (i) the Company's Common Stock or warrants
for Common Stock, or (ii) shares or warrants for shares, of any other class or
series of capital stock of the Company, by whatever name called, in which the
aggregate gross proceeds to the Company from one or more persons or entities not
"Stockholders" of the Company or "Affiliates" of such Stockholders (as each such
term is defined in the Stockholders' Agreement of the Company entered into in
connection with its Plan of Recapitalization at or about the time of issuance of
this Note) are at least $10,000,000, but excluding a Change of Control. To the
extent that this Note is not converted in accordance with this Section, upon the
closing of the Next Financing (evidenced by the execution of a purchase
agreement or similar commitment of the Company to issue its securities), the
conversion privilege provided by this Section 5 shall terminate and be of no
further force and effect.

          (b) Notice of Next Financing. The Company shall deliver to the Holder
a notice at least 20 days prior to any Next Financing describing in reasonable
detail all material terms of such Next Financing.

          (c) Mechanics of Conversion. Upon the Holder's election to convert
this Note, the specified part of the outstanding principal, accrued interest of
the Note shall be converted without any further action by the Holder and whether
or not the Note is surrendered to the Company or its transfer agent. The Company
shall not be obligated to issue certificates

<PAGE>

evidencing the shares of the securities issuable upon conversion unless such
Note is either delivered to the Company or its transfer agent (in exchange for a
replacement Note from the Company to the extent that conversion leaves some
indebtedness unpaid), or the Holder notifies the Company or its transfer agent
that such Note has been lost, stolen or destroyed and executes an agreement
reasonably satisfactory to the Company to indemnify the Company from any loss
incurred by it in connection with such Note. The Company shall, as soon as
practicable after such delivery, or such agreement and indemnification, issue
and deliver at such office to such holder of such Note, a certificate or
certificates for the number of securities to which the Holder shall be entitled
and a check payable to the Holder in the amount of any cash amounts payable as
the result of a conversion into fractional shares of the securities. Such
conversion (at the Holder's option) shall be deemed to have been made
immediately prior to the closing of the Next Financing. The person or persons
entitled to receive the securities issuable upon such conversion shall be
treated for all purposes as the record holder or holders of such securities on
such date.

     6. Representations and Warranties of the Holder.

          (a) Investment. The Holder is acquiring this Note, and the securities
into which this Note may be converted, for his, her or its own account for
investment and not with a view to, or for sale in connection with, any
distribution thereof, nor with any present intention of distributing or selling
the same; and such Holder has no present or contemplated agreement, undertaking,
arrangement, obligation, indebtedness or commitment providing for the
disposition thereof. Such Holder is an "accredited investor" as defined in Rule
501(a) under the Securities Act of 1933, as amended.

          (b) Authority. The Holder has full power and authority to enter into
and to perform this Note in accordance with their terms. If the Holder is a
corporation, limited liability company, partnership or trust, it represents that
it has not been organized, reorganized or recapitalized specifically for the
purpose of investing in the Company.

          (c) Experience. The Holder acknowledges that he, she or it has made
detailed inquiry concerning the Company, its business and its personnel; the
officers of the Company have made available to such Holder any and all written
information which he, she or it has requested and have answered to such Holder's
satisfaction all inquiries made by such Holder; and such Holder has sufficient
knowledge and experience in finance and business that he, she or it is capable
of evaluating the risks and merits of his, her or its investment in the Company
and such Holder is able financially to bear the risks thereof.

     7. Attorneys Fees. If the indebtedness represented by this Note or any part
thereof or any right of the Holder is collected or otherwise sought to be
enforced in bankruptcy, receivership or other judicial proceedings or if the
Holder of this Note engages attorneys for collection of this Note after default,
the Company agrees to pay, in addition to the principal and interest payable
hereunder, reasonable attorneys' fees and costs incurred by the Holder at any
time.

<PAGE>

     8. Notices. All notices and other communications required or permitted
hereunder shall be in writing and may be delivered in person or by facsimile,
electronic mail, or overnight courier, addressed (a) if to the Holder, at the
address for payments referred to in Section 1(f), or at such other address as
such Holder shall have furnished to the Company in writing, or (b) if to the
Company, to its address set forth on the signature page of this Note and
addressed to the attention of the Secretary, or at such other address as the
Company shall have furnished to the Holder with a copy to Charles F. Niemeth,
Esq., O'Melveny & Myers LLP, Times Square Tower, 7 Times Square, New York, NY
10036, facsimile number (212) 326-2061. All such notices and other
communications shall be deemed given upon personal delivery, upon confirmation
of facsimile transfer or upon confirmation of electronic mail transmission or
upon delivery by courier.

     9. Governing Law. This Agreement shall be governed by and construed under
the internal laws of the State of New York without reference to principles of
conflict of law or choice of laws, including the Uniform Commercial Code (the
"UCC").

     10. No Personal Liability of Officers or Directors. In no event shall any
officer or director of the Company be personally liable on this full recourse
Note of the Company for any amount due hereunder.

     11. Severability. If any provision of this Note shall be held to be
illegal, invalid or unenforceable, such illegality, invalidity or
unenforceability shall attach only to such provision and shall not in any manner
affect or render illegal, invalid or unenforceable any other provision of this
Note, and this Note shall be carried out as if any such illegal, invalid or
unenforceable provision were not contained herein.

     12. WAIVER OF JURY TRIAL. EACH OF THE HOLDER AND THE COMPANY WAIVE ANY AND
ALL RESPECTIVE RIGHTS TO TRIAL BY JURY OF ANY DISPUTE, CLAIM, OR CAUSE OF
ACTION, DIRECTLY OR INDIRECTLY, BASED UPON, ARISING OUT OF, RELATED TO, OR
AFFECTING THE NOTE, ANY OF THE RIGHTS, INTERESTS OR REMEDIES OF ANY PARTY WITH
RESPECT TO THIS NOTE, OR ANY RELATED TRANSACTION OR ACTION OR OMISSION,
INCLUDING WITH RESPECT TO ANY LITIGATION OF ANY ALLEGATION OF ANY BREACH OF
CONTRACT, TORT, WRONG OR EQUITABLE RIGHT OR REMEDY OF ANY KIND, AND ANY AND ALL
SUCH DISPUTES, CLAIMS OR CAUSES OF ACTION SHALL BE RESOLVED BY A COURT WITHOUT A
JURY.

OMRIX BIOPHARMACEUTICALS, INC.


By: /s/ Authorized Officer
    ---------------------------------
Name:   Authorized Officer
      -------------------------------
Title:  Authorized Officer
       ------------------------------

Address: [__________________________]

[___________________________________]

<PAGE>

Agreed and accepted as of the date at the top of this Note:

[___________________________________]


By: /s/ Philippe Romagnoli
    ---------------------------------
Its:
     --------------------------------


By:     Philippe Romagnoli
    ---------------------------------