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                                                                   Exhibit 10.37


                              AMENDED AND RESTATED
                              SEVERANCE AGREEMENT


         This Amended and Restated Severance Agreement is made as of the 7th day
of May 2004, between Enzon Pharmaceuticals, Inc., a Delaware corporation, with
offices in Bridgewater, New Jersey (the "Company"), and RALPH DEL CAMPO
("Executive"), a resident of New Jersey.

                                   BACKGROUND

         A. The Company and Executive previously entered into a Severance
Agreement dated 12/27/03 (the "Previous Agreement"). The parties hereto desire
that this Amended and Restated Severance Agreement (this "Agreement") supercede
the Previous Agreement.

         B. This Agreement is intended to specify the financial arrangements
that the Company will provide to the Executive upon Executive's separation from
employment with the Company under any of the circumstances described herein.

         C. Executive is employed by the Company in the capacity of S.V.P.,
OPERATIONS, and, as such, is a key executive of the Company.

         D. This Agreement is entered into by the Company in the belief that it
is in the best interests of the Company and its shareholders to provide stable
conditions of employment for Executive notwithstanding the possibility, threat
or occurrence of certain types of change in control, thereby enhancing the
Company's ability to attract and retain highly qualified people.

         E. The Company believes that it is important that it receive certain
assurances with respect to its Confidential Information, proprietary
information, intellectual property, trade secrets and Executive's work product,
and that the Company receive certain protections with respect to Executive's
activities following termination of Executive's employment, and the Company is
willing to offer Executive the compensation, bonuses and other benefits set
forth in this Agreement in order to obtain such assurances and protections.

                                      TERMS

         To assure the Company that it will have the continued dedication of
Executive notwithstanding the possibility, threat or occurrence of a bid to take
over control of the Company, and to induce Executive to remain in the employ of
the Company, in consideration of the foregoing premises and for other good and
valuable consideration, the Company and Executive agree as follows:

         1. Term of Agreement. The term of this Agreement ("Term") shall
commence on the date hereof as first written above and shall continue through
December 31, 2004; provided that commencing on January 1, 2005 and each January
1 thereafter, the term of this Agreement shall automatically be extended for one
additional year unless not later than September 30 of the preceding year, the
Company shall have given notice that it does not wish to extend this Agreement;
and provided, further, that notwithstanding any such notice by the Company not
to extend, in the event that there occurs, during the Term, a Change in Control,
as defined in Section 6(c) hereof, this Agreement shall continue in effect for a
period of 12 months beyond the date of such Change in Control.

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         2. Severance upon Termination without Cause or Termination by Executive
for Good Reason in Connection with Change in Control. Subject to the limitation
set forth in Section 3 hereof, in the event the Company terminates Executive's
employment without Cause, or in the event of a Termination by Executive for Good
Reason, and either such termination occurs within the period which commences
ninety (90) days before and ends one (1) year following a Change in Control:


                  (a) Executive shall receive his or her Base Salary through the
         date of termination;

                  (b) Executive shall receive a pro rated portion of the Target
         Bonus (based on the Base Salary at the time of such termination) which
         would have been payable to Executive for the fiscal year during which
         such termination occurs;

                  (c) in the event of a Change in Control defined in Section
         7(c)(i)-(vi), Executive shall receive cash payments equal to ONE AND
         ONE-HALF (1 1/2) TIMES the sum of the following: (i) his or her Base
         Salary at the time of such termination and (ii) the Target Bonus (based
         on the Base Salary immediately prior to such termination) for the
         fiscal year in which such termination occurs;

                  (d) in the event of a Change in Control defined in Section
         7(c)(vii), Executive shall receive cash payments equal to THREE-FOURTHS
         (3/4) times the sum of the following: (i) his or her Base Salary at the
         time of such termination and (ii) the Target Bonus (based on the Base
         Salary immediately prior to such termination) for the fiscal year in
         which such termination occurs;

                  (d) Executive shall continue to be entitled to any deferred
         compensation and other unpaid amounts and benefits earned and vested
         prior to Executive's termination;

                  (e) if Executive and Executive's Family Members have medical
         and dental coverage on the date of such tennination under a group
         health plan sponsored by the Company, the Company will reimburse
         Executive for the total applicable premium cost for medical and dental
         coverage under COBRA for Executive and Executive's Family Members for a
         period of up to EIGHTEEN (18) MONTHS in the case of a Change in Control
         defined in Section 7(c)(i)-(vi), or NINE (9) MONTHS in the case of a
         Change in Control defined in Section 7(c)(vii), commencing on the date
         of such termination; provided, that the Company shall have no
         obligation to reimburse Executive for the premium cost of COBRA
         coverage as of the date Executive and Executive's Family Members become
         eligible to obtain comparable benefits from a subsequent employer;


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                  (f) the Company shall provide Executive outplacement
         assistance, as determined by the Company in its discretion.

         3. Effect of Change in Control. In the event of a Change of Control
(other than that described in Section 7(c)(vii) hereof), in addition to any
other consequences provided for in this Agreement,

                  (a) all options to acquire shares of the Company held by the
         Executive shall become fully vested immediately prior to the effective
         date of the Change in Control. Executive shall have a reasonable
         opportunity to exercise all or any portion of such options prior to the
         effective date of the Change in Control, and any options not exercised
         prior to the effective date of the Change in Control shall terminate as
         of the effective date of the Change in Control and will be of no
         further force or effect. To the extent that this section 3(a) is
         inconsistent with the provisions of the relevant plan and granting
         instruments under which such options were issued, the Company and
         Executive agree that such inconsistent provisions are hereby superceded
         and the provisions of this Section 3(a) shall govern; and

                  (b) all shares of restricted stock and/or restricted stock
         units awarded to Executive shall fully vest immediately prior to the
         Change in Control.

         4. Limitation. Notwithstanding anything stated in this Agreement to the
contrary, if the amounts that are payable and the benefits that are provided to
Executive under this Agreement either alone or together with other payments that
Executive has a right to receive from the Company or any of its affiliates (the
"Combined Amounts"), would constitute a "parachute payment" (as defined in Code
Section 280G or any successor provision), the Combined Amounts shall be reduced,
as necessary, to the largest amount as will result in no portion of the Combined
Amounts being either not deductible as a result of Code Section 280G (or any
successor provision) or subject to the excise tax imposed by Code Section 4999
(or any successor provision). The determination of any reduction in said amounts
and benefits pursuant to the foregoing provision shall be made by the Company in
good faith, and such determination shall be conclusive and binding on Executive;
provided, however, that notwithstanding the foregoing, the Company shall notify
Executive, as soon as possible after the date of Executive's termination of
employment (but in no event later than twenty (20) days prior to the payment
date of the sums due under Section 2) of the value attributed by the Company to
the continuation of health benefits (or payments related thereto) and the value
attributed by the Company to the acceleration (if any) of the vesting of options
and/or restricted stock and/or restricted stock units, and Executive shall have
the option to decline such benefits or the acceleration of the vesting of such
options and/or restricted stock and/or restricted stock units in a notice to the
Company given no later than ten (10) days prior to such payment date. If the
Combined Amounts (after having accounted for the reduction by the Company
described in the immediately preceding sentence) shall be disallowed in whole or
part as a deductible expense in determining the income tax liability of the
Company, Executive shall reimburse the company to the full extent of such
disallowance. The Company's Board of Directors shall enforce this obligation to
reimburse the Company immediately following such disallowance. The amounts
provided to Executive under this Agreement in connection with a Change in
Control, if any, shall be deemed allocated to such amounts and/or benefits to be
paid and/or provided as the Company's Board of Directors in its sole discretion
shall determine.

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         5. Time of Payments. All payments made to Executive under any of the
subsections of Section 2 which are based upon Executive's salary or bonus shall
be made at times and in a manner which is in accordance with the Company's
standard payroll practices for senior management; provided that any such
payments will be paid to Executive on or before the second anniversary of the
termination of Executive's employment.

         6. Release. Notwithstanding anything else herein to the contrary,
Executive shall not be entitled to realize or receive any termination related
benefits provided for under this Agreement, including, without limitation, all
post-termination payments and the acceleration of option or restricted stock or
restricted stock unit vesting schedules, unless Executive shall have executed
and delivered to the Company a full release (reasonably satisfactory to the
Company's counsel) of all claims against the Company and its affiliates,
successors and assigns.

         7. Definitions.

                  (a) "Base Salary" means Executive's annual base salary as
         established by the Board of Directors of the Company ("Board") or the
         Compensation Committee from time to time.

                  (b) "Cause" means:

                           (i) the willful engaging by Executive in illegal
                  conduct or gross misconduct which is demonstrably and
                  materially injurious to the Company; or

                           (ii) Executive's refusal or inability to perform the
                  duties of his or her position as an executive employed by the
                  Company, which refusal or inability is demonstrably and
                  materially injurious to the Company; or

                           (iii) Executive's breach of his or her obligations
                  under this Agreement or any employment agreement between the
                  Company and Executive, which breach is demonstrably and
                  materially injurious to the Company; or

                           (iv) Executive's failure, where applicable, to
                  maintain Executive's immigration status with the U.S.
                  Immigration and Naturalization Service or the Executive's
                  failure to maintain valid employment authorization to provide
                  services to the Company.

                           For purposes of this Section 6(b), no act or failure
                  to act on Executive's part shall be deemed "willful" unless
                  done, or omitted to be done, by Executive not in good faith
                  and without reasonable belief that Executive's action of
                  omission was in the best interest of the Company.
                  Notwithstanding the foregoing, with respect to the definitions
                  of Cause set forth in clauses (i)-(iii) above, Executive shall
                  not be deemed to have been terminated for Cause unless and
                  until the Company delivers to Executive a notice of such
                  termination for Cause. Such notice shall be in writing,
                  addressed to Executive, labeled "Personal and Confidential,"
                  and sent to the address for Executive set forth in Section
                  7(i) hereof. Any such notice shall describe, with
                  particularity, the conduct of Executive forming the basis for
                  such termination of employment. Any such notices shall become
                  effective on the 30th day following delivery thereof to
                  Executive if Executive has not cured the conduct identified in
                  such notice to the satisfaction of the Company, provided,
                  however, that the Company may elect to make such termination
                  effective immediately, in which case Executive's employment
                  shall terminate immediately upon delivery of the notice of
                  termination, but the Company shall continue to pay Executive
                  his or her salary during such 30-day period and the last day
                  of such 30-day period shall be deemed to be the date of
                  termination of his or her employment for purposes of any pro
                  rata calculations and determination of post-termination
                  periods under this agreement.

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                  (c) "Change in Control" means the following:

                           (i) "Board Change" which, for purposes of this
                  Agreement, shall have occurred if, over any twenty-four month
                  period, a majority of the seats (other than vacant seats) on
                  the Company's Board were to be occupied by individuals who
                  were neither (A) nominated by at least one-half (1/2) of the
                  directors then in office (but excluding, for purposes of
                  determining directors then in office, any director whose
                  initial assumption of office occurs as a result of either an
                  actual or threatened election contest, or other actual or
                  threatened solicitation of proxies or consents by or on behalf
                  of a Person (as defined herein) other than the Company or its
                  board of directors); nor (B) appointed by directors so
                  nominated, or

                           (ii) the acquisition by any individual, entity or
                  group (within the meaning of Section 13(d)(3) or 14(d)(2) of
                  the Securities Exchange Act of 1934 (the "Exchange Act"), (a
                  "Person") of beneficial ownership (within the meaning of Rule
                  13d-3 promulgated under the Exchange Act) of a majority of the
                  then outstanding voting securities of the Company; provided,
                  however, that the following acquisitions shall not constitute
                  a Change of Control: (1) any acquisition by the Company, or
                  (2) any acquisition by any employee benefit plan (or related
                  trust) sponsored or maintained by the Company or any
                  corporation controlled by the Company, or (3) any public
                  offering or private placement by the Company of its voting
                  securities; or

                           (iii) a consolidation of the Company with another
                  entity, or a merger of the Company with another entity in
                  which neither the Company nor a corporation that, prior to the
                  merger, was a subsidiary of the Company shall be the surviving
                  entity; or

                           (iv) a merger of the Company following which either
                  the Company or a corporation that, prior to the merger, was a
                  subsidiary of the Company shall be the surviving entity and a
                  majority of the then outstanding voting securities of the
                  Company is beneficially owned (within the meaning of
                  beneficial owner, as specified below) by a Person or Persons
                  who were not "beneficial owners," as defined in Rule l3d-3 of
                  the Exchange Act, of a majority of the Outstanding Company
                  Voting Securities immediately prior to such merger; or

                           (v) a voluntary or involuntary liquidation of the
                  Company;


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                           (vi) a sale or disposition by the Company of at least
                  80% of its assets in a single transaction or a series of
                  transactions (other than a sale or disposition of assets to a
                  subsidiary of the Company in a transaction not otherwise
                  involving a Change in Control or a change in control of such
                  subsidiary); or

                           (vii) anytime prior to December 31, 2005 someone
                  other than the person who is the Chief Executive Officer of
                  the Company as of the date hereof becomes the Company's chief
                  executive.

                           Transactions in which the Executive is part of the
                  acquiring group do not constitute a Change in Control.

                  (d) "Good Reason" means:

                           (i) any material adverse change in Executive's status
                  or position as an officer of the Company, including, without
                  limitation, any diminution in Executive's duties,
                  responsibilities or authority as of the Effective Date or the
                  assignment to Executive of any duties or responsibilities that
                  are inconsistent with Executive's status or position;
                  provided, however, that none of the foregoing shall be deemed
                  to have occurred by virtue of a change in Executive's
                  reporting relationship with respect to the Company's CEO as
                  long as Executive remains the Company's most senior Operations
                  executive;

                           (ii) a reduction in Executive's Base Salary or Target
                  Bonus; or

                           (iii) the relocation of the Company's principal
                  executive offices to a location more than thirty-five (35)
                  miles from the location of such offices (other than a
                  relocation that results in the location of the offices in
                  closer proximity to Executive's residence) or the Company
                  requiring Executive to be based anywhere other than the
                  Company's principal executive offices, except for required
                  travel substantially consistent with Executive's business
                  obligations; provided that

                           (iv) prior to Executive being permitted to terminate
                  his employment for Good Reason hereunder, the Company shall
                  have failed to cure any alleged condition described in
                  subparagraphs (i) - (iii) above within the "Cure Period"
                  (defined below). For purposes of this Paragraph 7(d), the term
                  "Cure Period" means the period commencing on the date of
                  receipt of Executive's notice referred to in the preceding
                  sentence and ending on the earlier of (A) sixty (60) days
                  thereafter or (B) two weeks prior to the first anniversary of
                  the relevant Change in Control.

                  (e) "Target Bonus" means the performance based cash bonus as
         determined under the Company's bonus plan for management (and any
         successor bonus plan covering management). The amount of Executive's
         annual Target Bonus is determined by the Board in its discretion
         following consultation between the Chief Executive Officer and
         Executive prior to, or within sixty (60) days after the commencement
         of, each fiscal year.

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         8. Miscellaneous.

                  (a) No Funding of Severance. Nothing contained in this
         Agreement or otherwise shall require the Company to segregate, earmark
         or otherwise set aside any funds or other assets to provide for any
         payments required to be made under Section 2 hereof, and the rights of
         Executive to any benefits hereunder shall be solely those of a general,
         unsecured creditor of the Company.

                  (b) Beneficiaries. In the event of Executive's death, any
         amount or benefit payable or distributable to Executive pursuant to
         this Agreement shall be paid to the beneficiary designated by Executive
         for such purpose in the last written instrument received by the Company
         prior to Executive's death, if any, or, if no beneficiary has been
         designated, to Executive's estate, but such designation shall not be
         deemed to supersede any beneficiary designation under any benefit plan
         of the Company.

                  (c) Entire Agreement. This Agreement contains the entire
         understanding between the parties hereto with respect to the subject
         matter hereof and supersedes any prior understandings, agreements or
         representations, written or oral, relating to the subject matter
         hereof.

                  (d) Counterparts. This Agreement may be executed in separate
         counterparts, each of which will be an original and all of which taken
         together shall constitute one and the same agreement, and any party
         hereto may execute this Agreement by signing any such counterpart.

                  (e) Severability. Whenever possible, each provision of this
         Agreement shall be interpreted in such a manner as to be effective and
         valid under applicable law but if any provision of this Agreement is
         held to be invalid, illegal or unenforceable under any applicable law
         or rule, the validity, legality and enforceability of the other
         provision of this Agreement will not be affected or impaired thereby.

                  (f) Successors and Assigns. This Agreement shall be binding
         upon and inure to the benefit of the parties hereto and their
         respective heirs, personal representatives and, to the extent permitted
         by Section 7(g), successors and assigns. The Company will require its
         successors to expressly assume its obligations under this Agreement.

                  (g) Assignability. Neither this Agreement nor any right,
         remedy, obligation or liability arising hereunder or by reason hereof
         shall be assignable (including by operation of law) by either party
         without the prior written consent of the other party to this Agreement.

                  (h) Modification, Amendment, Waiver or Termination. No
         provision of this Agreement may be modified, amended, waived or
         terminated except by an instrument in writing signed by the parties to
         this Agreement. No course of dealing between the parties will modify,
         amend, waive or terminate any provision of this Agreement or any rights
         or obligations of any party under or by reason of this Agreement. No
         delay on the part of the Company in exercising any right hereunder
         shall operate as a waiver of such right. No waiver, express or implied,
         by the Company of any right or any breach by Executive shall constitute
         a waiver of any other right or breach by Executive.

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                  (i) Notices. All notices, consents, requests, instructions,
         approvals or other communications provided for herein shall be in
         writing and delivered by personal delivery, overnight courier, mail,
         electronic facsimile or e-mail addressed to the receiving party at the
         address set forth herein. All such communications shall be effective
         when received.

         Address for the Executive:

                  Ralph del Campo
                  685 Route 202/206
                  Bridgewater, NJ 08807


         Address for the Company:

                  Enzon Pharmaceuticals, Inc.
                  685 Route 202/206
                  Bridgewater, New Jersey 08807
                  Attn: Vice President, Human Resources

                  Any party may change the address set forth above by notice to
         each other party given as provided herein.

                  (j) Headings. The headings contained in this Agreement are for
         reference purposes only and shall not in any way affect the meaning or
         interpretation of this Agreement.

                  (k) Governing Law. ALL MATTERS RELATING TO THE INTERPRETATION,
         CONSTRUCTION, VALIDITY AND ENFORCEMENT OF THIS AGREEMENT SHALL BE
         GOVERNED BY THE INTERNAL LAWS OF THE STATE OF NEW JERSEY, WITHOUT
         GIVING EFFECT TO ANY CHOICE OF LAW PROVISIONS THEREOF.

                  (l) Arbitration. Any claim or controversy arising out of or
         relating to this Agreement or the breach hereof shall be settled by
         arbitration in accordance with the laws of the State of New Jersey.
         Such arbitration shall be conducted in the State of New Jersey in
         accordance with the rules then existing of the American Arbitration
         Association. Judgment upon the award rendered by the arbitrators may be
         entered in any court having jurisdiction thereof. In the event of any
         dispute arising under this Agreement, the respective parties shall be
         responsible for the payment of their own legal fees and disbursements.


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                  (m) Third-Party Benefit. Nothing in this Agreement, express or
         implied, is intended to confer upon any third party any rights,
         remedies, obligations or liabilities of any nature whatsoever.

                  (n) Withholding Taxes. The Company may withhold from any
         benefits payable under this Agreement or any other agreement all
         federal, state, city or other taxes as shall be required pursuant to
         any law or governmental regulation or ruling. Executive hereby agrees
         to indemnify and hold harmless the Company should the Company fail to
         withhold tax from any such payment from which tax is required to be
         withheld.

                  (o) No Right to Continued Employment. Executive understands
         that this Severance Agreement is not an employment contract and nothing
         contained herein creates any right to continuous employment with the
         Company, or to employment by the Company for any specified period of
         time.

                  (p) Termination of Previous Agreement. The Previous Agreement
         is hereby terminated and of no further force or effect.

IN WITNESS WHEREOF, the parties hereto have executed this Agreement as of the
date first set forth above.


ENZON PHARMACEUTICALS, INC.


By: /s/ Arthur J. Higgins
   ----------------------------------------
   Arthur J. Higgins,
   President and Chief Executive Officer


   /s/ Ralph del Campo
   ----------------------------------------
   Ralph del Campo



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