<PAGE>

        As filed with the Securities and Exchange Commission on January 29, 2007
                                                 Registration No. 333-__________
================================================================================

                                  UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549

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

                                    FORM S-8
                             REGISTRATION STATEMENT
                        UNDER THE SECURITIES ACT OF 1933

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

                           ENZON PHARMACEUTICALS, INC.
             (Exact name of Registrant as specified in its charter)

                  DELAWARE                               22-2372868
      (State or other jurisdiction of                  (I.R.S. Employer
     incorporation or organization)                   Identification No.)

                                685 ROUTE 202/206
                          BRIDGEWATER, NEW JERSEY 08807
                    (Address of principal executive offices)

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

          ENZON PHARMACEUTICALS, INC. 2007 EMPLOYEE STOCK PURCHASE PLAN

                            (Full title of the plan)

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

                              JEFFREY H. BUCHALTER
                             CHIEF EXECUTIVE OFFICER
                           ENZON PHARMACEUTICALS, INC.
                                685 ROUTE 202/206
                          BRIDGEWATER, NEW JERSEY 08807
                     (Name and address of agent for service)

                                 (908) 541-8600
          (Telephone number, including area code, of agent for service)
                             -----------------------
                                   Copies to:

   Scott Waldman, Esq.                             Kevin T. Collins, Esq.
   Senior Director and Associate General Counsel   Heller Ehrman LLP
   Enzon Pharmaceuticals, Inc.                     Times Square Tower
   685 Route 202/206                               7 Times Square
   Bridgewater, New Jersey 08807                   New York, New York 10036
   Telephone - (908) 541-8600                      Telephone - (212) 832-8300

                         CALCULATION OF REGISTRATION FEE

<TABLE>
<CAPTION>
                                                                                                    Amount of
Title of each class of securities  Amount to be      Proposed maximum         Proposed maximum     registration
         to be registered          registered    offering price per share aggregate offering price      fee
---------------------------------- ------------- ------------------------ ------------------------ ------------
<S>                                <C>           <C>                      <C>                      <C>
Common Stock, $0.01 par value
per share (1).....................  1,000,000 (2)       $8.72 (3)               $8,720,000           $933.04
</TABLE>

----
(1)   One preferred stock purchase right will attach to and trade with each
      share of common stock sold in the offering. These rights are also covered
      by this registration statement and the value attributable to them, if any,
      is reflected in the market price of the common stock.

(2)   This Registration Statement covers the 1,000,000 shares of common stock
      available for future grants under the Enzon Pharmaceuticals, Inc. 2007
      Employee Stock Purchase Plan (the "ESPP"), plus an indeterminate number of
      additional shares which may be offered and issued to prevent dilution
      resulting from stock splits, stock dividends or similar transactions.

(3)   Estimated solely for the purpose of calculating the registration fee in
      accordance with Rule 457(h) and Rule 457(c) under the Securities Act of
      1933, as amended, based upon the average of the high and low prices of the
      registrant's Common Stock on the Nasdaq Global Market on January 24, 2007.

================================================================================
<PAGE>

                                     PART I
               INFORMATION REQUIRED IN THE SECTION 10(A)PROSPECTUS

ITEM 1. PLAN INFORMATION.*

ITEM 2. REGISTRANT INFORMATION AND EMPLOYEE PLAN ANNUAL INFORMATION.*

*Information required by Part I to be contained in the Section 10(a) prospectus
is omitted from this registration statement in accordance with Rule 428 under
the Securities Act and the Note to Part I of Form S-8.

                                     PART II
               INFORMATION REQUIRED IN THE REGISTRATION STATEMENT

ITEM 3. INCORPORATION OF DOCUMENTS BY REFERENCE.

      The following documents filed with the Securities and Exchange Commission
(the "Commission") are hereby incorporated by reference:

      (a) The registrant's Transition Report on Form 10-K for the transition
period ended December 31, 2005, filed with the Commission on March 3, 2006,
pursuant to Section 13(a) of the Securities Exchange Act of 1934, as amended
(the "Exchange Act").

      (b) All other reports filed pursuant to Section 13(a) or 15(d) of the
Exchange Act since the end of the fiscal period covered by the Transition Report
referred to in (a) above.

      (c) The description of the registrant's Common Stock, par value $.01 per
share, as contained in a registration statement on Form 8-A filed on October 29,
1984, as amended by Form 8-A/A filed on October 15, 1990, including any
amendment or report filed for the purpose of updating such description.

      (d) The description of the registrant's Series B Preferred Stock Purchase
Rights as contained in a registration statement on Form 8-A filed on May 22,
2002, including any amendment or report filed for the purpose of updating such
description.

      All documents subsequently filed by the registrant pursuant to Sections
13(a), 13(c), 14 and 15(d) of the Exchange Act, prior to the filing of a
post-effective amendment which indicates that all securities offered hereby have
been sold or which deregisters all securities then remaining unsold, shall be
deemed to be incorporated by reference in this registration statement and to be
part hereof from the date of filing such documents.

ITEM 4. DESCRIPTION OF SECURITIES.

      Not applicable.

ITEM 5. INTERESTS OF NAMED EXPERTS AND COUNSEL.

      Not applicable.

ITEM 6. INDEMNIFICATION OF DIRECTORS AND OFFICERS.

      Section 145 of the Delaware General Corporation Law (the "DGCL") empowers
a corporation to indemnify any person who was or is a party or is threatened to
be made a party to any threatened, pending or completed action, suit or
proceeding, whether civil, criminal, administrative or investigative (other than
an action by or in the right of the corporation) by reason of the fact that he
or she is or was a director, officer, employee or agent of the corporation or is
or was serving at the request of the corporation as a director, officer,
employee or agent of

                                        1
<PAGE>

another corporation or other enterprise, against expenses (including attorneys'
fees), judgments, fines and amounts paid in settlement actually and reasonably
incurred by him or her in connection with such action, suit or proceeding if he
or she acted in good faith and in a manner he or she reasonably believed to be
in, or not opposed to, the best interests of the corporation, and, with respect
to any criminal action or proceeding, had no reasonable cause to believe his or
her conduct was unlawful.

      Section 145 also empowers a corporation to indemnify any person who was or
is a party or is threatened to be made a party to any threatened, pending or
completed action or suit by or in the right of the corporation to procure a
judgment in its favor by reason of the fact that such person acted in any of the
capacities set forth above, against expenses (including attorneys' fees)
actually and reasonably incurred by him or her in connection with the defense or
settlement of such action or suit if he or she acted under similar standards,
except that no indemnification may be made in respect of any claim, issue or
matter as to which such person shall have been adjudged to be liable to the
corporation unless, and only to the extent that, the Delaware Court of Chancery
or the court in which such action was brought shall determine that despite the
adjudication of liability such person is fairly and reasonably entitled to
indemnity, for such expenses which the Delaware Court of Chancery or such other
court shall deem proper.

      Section 145 further provides that to the extent a director, officer,
employee or agent of a corporation has been successful in the defense of any
action, suit or proceeding referred to above or in the defense of any claim,
issue or matter therein, he or she shall be indemnified against expenses
(including attorneys' fees) actually and reasonably incurred by him or her in
connection therewith, that indemnification provided for by Section 145 shall not
be deemed exclusive of any other rights to which the indemnified party may be
entitled; and that the corporation is empowered to purchase and maintain
insurance on behalf of any person who is or was a director, officer, employee or
agent of the corporation against any liability asserted against him or her in
any such capacity or arising out of his or her status as such, whether or not
the corporation would have the power to indemnify him or her against such
liability under Section 145.

      Section 102(b)(7) of the DGCL enables a corporation in its certificate of
incorporation to limit the personal liability of members of its board of
directors for violation of a director's fiduciary duty of care. Article 10 of
the Company's certificate of incorporation, as authorized by Section 102(b)(7),
provides that a director shall not be liable to the Company for breach of a
fiduciary duty, except for liability:

            -     for any breach of the director's duty of loyalty to the
                  Company or the Company's stockholders;

            -     for acts or omissions not in good faith or which involve
                  intentional misconduct or a knowing violation of law;

            -     under section 174 of the DGCL providing for liability of
                  directors for unlawful payment of dividends or unlawful stock
                  purchases or redemptions;

            -     for any transaction from which a director derived an improper
                  benefit; or

            -     for any act or omission occurring prior to the date when
                  Article 10 became effective.

      Section 8.1 of the Company's bylaws provides for the indemnification, to
the fullest extent authorized by law, of any person made, or threatened to be
made, a party to an action or proceeding, whether criminal, civil,
administrative or investigative, against expenses, judgments, fines, and amounts
paid in settlement incurred in connection with such action or proceeding, by
reason of the fact that such person is or was a director or officer of the
Company. The Company's Directors' and Officers' Liability Insurance, which is
provided for under Section 8.3 of the Company's bylaws, insures directors and
officers against any liability arising out of such person's status as a director
or officer, and insures the Company against its obligations to indemnify its
directors and officers.

      Certain of the Company's officers and directors have executed indemnity
agreements which supplement the protections provided by the Company's
certificate of incorporation and bylaws. These agreements require the

                                        2
<PAGE>

Company to pay for any damages, judgments, settlements, costs and expenses for
the defense of legal actions, claims, proceedings and appeals due to any actual
or alleged breach of duty, neglect, error, misstatement, misleading statement,
omission or other act done, suffered or wrongfully attempted by the officer or
director. If the Company does not pay such costs and expenses within 90 days
after it receives a written claim, such officers or directors may bring a suit
against the Company to recover the unpaid amount of the claim. If such officer
or director is successful, the Company will be required to pay for the expenses
incurred relating to the claim.

Item 7. EXEMPTION FROM REGISTRATION CLAIMED. Not applicable.

Item 8. EXHIBITS.

<TABLE>
<CAPTION>
Exhibit
Number
<S>      <C>
4.1      Rights Agreement dated as of May 17, 2002 ("Rights Agreement") between the
         Company and Continental Stock Transfer & Trust Company, as Rights Agent
         (incorporated by reference to exhibit 4.2 to the Company's Form 8-A
         (File No. 000-12957) filed with the Commission on May 22, 2002).

5.1      Opinion of Heller Ehrman LLP.

10.1     2007 Employee Stock Purchase Plan.

23.1     Consent of Heller Ehrman LLP (included in Exhibit 5.1).

23.2     Consent of Independent Registered Public Accounting Firm.

24.1     Powers of Attorney (included in signature page to this registration statement).
</TABLE>

Item 9. UNDERTAKINGS.

      (a) The undersigned registrant hereby undertakes:

            (1) To file, during any period in which offers or sales are being
made, a post-effective amendment to this registration statement:

                  (i) To include any prospectus required by Section 10(a)(3) of
the Securities Act;

                  (ii) To reflect in the prospectus any facts or events arising
after the effective date of the registration statement (or the most recent
post-effective amendment thereof) which, individually or in the aggregate,
represent a fundamental change in the information set forth in the registration
statement. Notwithstanding the foregoing, any increase or decrease in volume of
securities offered (if the total dollar value of securities offered would not
exceed that which was registered) and any deviation from the low or high end of
the estimated maximum offering range may be reflected in the form of prospectus
filed with the Commission pursuant to Rule 424(b) if, in the aggregate, the
changes in volume and price represent no more than a 20% change in the maximum
aggregate offering price set forth in the "Calculation of Registration Fee"
table in the effective registration statement; and

                  (iii) To include any material information with respect to the
plan of distribution not previously disclosed in the registration statement or
any material change to such information in the registration statement;

      Provided, however, that paragraphs (a)(1)(i) and (a)(1)(ii) above do not
apply if the information required to be included in a post-effective amendment
by those paragraphs is contained in periodic reports filed with or furnished to
the Commission by the registrant pursuant to Section 13 or Section 15(d) of the
Exchange Act that are incorporated by reference in the registration statement.

                                        3
<PAGE>

            (2) That, for the purpose of determining any liability under the
Securities Act, each such post-effective amendment shall be deemed to be a new
registration statement relating to the securities offered therein, and the
offering of such securities at that time shall be deemed to be the initial bona
fide offering thereof.

            (3) To remove from registration by means of a post-effective
amendment any of the securities being registered which remain unsold at the
termination of the offering.

      (b) The undersigned registrant hereby undertakes that, for purposes of
determining any liability under the Securities Act, each filing of the
registrant's annual report pursuant to Section 13(a) or Section 15(d) of the
Exchange Act (and, where applicable, each filing of an employee benefit plan's
annual report pursuant to Section 15(d) of the Exchange Act) that is
incorporated by reference in the registration statement shall be deemed to be a
new registration statement relating to the securities offered therein, and the
offering of such securities at that time shall be deemed to be the initial bona
fide offering thereof.

      (c) Insofar as the indemnification for liabilities arising under the
Securities Act may be permitted to directors, officers and controlling persons
of the registrant pursuant to the foregoing provisions, or otherwise, the
registrant has been advised that in the opinion of the Commission such
indemnification is against public policy as expressed in the Securities Act and
is, therefore, unenforceable. In the event that a claim for indemnification
against such liabilities (other than the payment by the registrant of expenses
incurred or paid by a director, officer or controlling person of the registrant
in a successful defense of any action, suit or proceeding) is asserted by such
director, officer or controlling person in connection with the securities being
registered hereunder, the registrant will, unless in the opinion of its counsel
the matter has been settled by controlling precedent, submit to a court of
appropriate jurisdiction the question of whether such indemnification by it is
against public policy as expressed in the Securities Act and will be governed by
the final adjudication of such issue.

                            [Signature Pages Follow]

                                        4
<PAGE>

                                   SIGNATURES

      Pursuant to the requirements of the Securities Act of 1933, the registrant
certifies that it has reasonable grounds to believe that it meets all of the
requirements for filing on Form S-8 and has duly caused this Registration
Statement to be signed on its behalf by the undersigned, thereunto duly
authorized, in the City of Bridgewater, State of New Jersey, on January 26,
2007.

                                 Enzon Pharmaceuticals, Inc.

                                 By: /s/ Jeffrey H. Buchalter
                                     --------------------------------------
                                     Jeffrey H. Buchalter
                                     President, Chief Executive Officer and
                                     Chairman of the Board (Principal Executive
                                     Officer)

                                POWER OF ATTORNEY

      KNOW ALL PERSONS BY THESE PRESENTS, that each person whose signature
appears below constitutes and appoints Jeffrey H. Buchalter and Craig A. Tooman,
jointly and severally, his or her attorneys-in-fact and agents, each with the
power of substitution and resubstitution, for him or her and in his or her name,
place or stead, in any and all capacities, to sign any amendments to this
Registration Statement on Form S-8, and to file such amendments, together with
exhibits and other documents in connection therewith, with the Securities and
Exchange Commission, granting to each attorney-in-fact and agent, full power and
authority to do and perform each and every act and thing requisite and necessary
to be done in and about the premises, as fully as he or she might or could do in
person, and ratifying and confirming all that the attorneys-in-fact and agents,
or his or her substitute or substitutes, may do or cause to be done by virtue
hereof.

      Pursuant to the requirements of the Securities Act of 1933, this
Registration Statement has been signed by the following persons in the
capacities and on the dates indicated.

<TABLE>
<CAPTION>
         Signature                               Title                              Date
----------------------------  -----------------------------------------------  ----------------
<S>                           <C>                                              <C>
/s/ Craig A. Tooman           Executive Vice President, Finance and Chief      January 26, 2007
---------------------------   Financial Officer (Principal Financial
Craig A. Tooman               Officer)

/s/ Jeffrey H. Buchalter      President, Chief Executive Officer and Chairman  January 26, 2007
---------------------------   of the Board (Principal Executive Officer)
Jeffrey H. Buchalter

/s/ Goran Ando                Director                                         January 26, 2007
---------------------------
Goran Ando

/s/ Rolf A. Classon           Director                                         January 26, 2007
---------------------------
Rolf A. Classon

/s/ Robert LeBuhn             Director                                         January 26, 2007
---------------------------
Robert LeBuhn

/s/ Victor P. Micati          Director                                         January 26, 2007
---------------------------
Victor P. Micati

/s/ Phillip M. Renfro         Director                                         January 26, 2007
---------------------------
Phillip M. Renfro

/s/ Robert C. Salisbury       Director                                         January 26, 2007
---------------------------
Robert C. Salisbury
</TABLE>

                                       5
<PAGE>

                                INDEX TO EXHIBITS

<TABLE>
<CAPTION>
Exhibit
Number
<S>    <C>
5.1    Opinion of Heller Ehrman LLP.

10.1   2007 Employee Stock Purchase Plan.

23.1   Consent of Heller Ehrman LLP (included in Exhibit 5.1).

23.2   Consent of Independent Registered Public Accounting Firm.

24.1   Powers of Attorney (included in signature page to this registration statement).
</TABLE>
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{"company-data": {"conformed-name": "ENZON PHARMACEUTICALS INC", "cik": "0000727510", "assigned-sic": "2836", "irs-number": "222372868", "state-of-incorporation": "DE", "fiscal-year-end": "1231"}, "filing-values": {"form-type": "S-8", "act": "33", "file-number": "333-140282", "film-number": "07561055"}, "business-address": {"street1": "685 ROUTE 202/206", "city": "BRIDGEWATER", "state": "NJ", "zip": "08807", "phone": "908 541 8671"}, "mail-address": {"street1": "685 ROUTE 202/206", "street2": "ATT:  GENERAL COUNSEL", "city": "BRIDGEWATER", "state": "NJ", "zip": "08807"}, "former-company": [{"former-conformed-name": "ENZON PHARMACEUTICALS  INC", "date-changed": "20021211"}, {"former-conformed-name": "ENZON PHARMACEUTICAL  INC", "date-changed": "20021210"}, {"former-conformed-name": "ENZON INC", "date-changed": "19920703"}]}
As filed with the Securities and Exchange Commission on January 29, 2007
                                                 Registration No. 333-__________
================================================================================

                                  UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549

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

                                    FORM S-8
                             REGISTRATION STATEMENT
                        UNDER THE SECURITIES ACT OF 1933

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

                           ENZON PHARMACEUTICALS, INC.
             (Exact name of Registrant as specified in its charter)

                  DELAWARE                               22-2372868
      (State or other jurisdiction of                  (I.R.S. Employer
     incorporation or organization)                   Identification No.)

                                685 ROUTE 202/206
                          BRIDGEWATER, NEW JERSEY 08807
                    (Address of principal executive offices)

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

          ENZON PHARMACEUTICALS, INC. 2007 EMPLOYEE STOCK PURCHASE PLAN

                            (Full title of the plan)

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

                              JEFFREY H. BUCHALTER
                             CHIEF EXECUTIVE OFFICER
                           ENZON PHARMACEUTICALS, INC.
                                685 ROUTE 202/206
                          BRIDGEWATER, NEW JERSEY 08807
                     (Name and address of agent for service)

                                 (908) 541-8600
          (Telephone number, including area code, of agent for service)
                             -----------------------
                                   Copies to:

   Scott Waldman, Esq.                             Kevin T. Collins, Esq.
   Senior Director and Associate General Counsel   Heller Ehrman LLP
   Enzon Pharmaceuticals, Inc.                     Times Square Tower
   685 Route 202/206                               7 Times Square
   Bridgewater, New Jersey 08807                   New York, New York 10036
   Telephone - (908) 541-8600                      Telephone - (212) 832-8300

                         CALCULATION OF REGISTRATION FEE
Amount of
Title of each class of securities  Amount to be      Proposed maximum         Proposed maximum     registration
         to be registered          registered    offering price per share aggregate offering price      fee
---------------------------------- ------------- ------------------------ ------------------------ ------------
Common Stock, $0.01 par value
per share (1).....................  1,000,000 (2)       $8.72 (3)               $8,720,000           $933.04
----
(1)   One preferred stock purchase right will attach to and trade with each
      share of common stock sold in the offering. These rights are also covered
      by this registration statement and the value attributable to them, if any,
      is reflected in the market price of the common stock.

(2)   This Registration Statement covers the 1,000,000 shares of common stock
      available for future grants under the Enzon Pharmaceuticals, Inc. 2007
      Employee Stock Purchase Plan (the "ESPP"), plus an indeterminate number of
      additional shares which may be offered and issued to prevent dilution
      resulting from stock splits, stock dividends or similar transactions.

(3)   Estimated solely for the purpose of calculating the registration fee in
      accordance with Rule 457(h) and Rule 457(c) under the Securities Act of
      1933, as amended, based upon the average of the high and low prices of the
      registrant's Common Stock on the Nasdaq Global Market on January 24, 2007.

================================================================================
PART I
               INFORMATION REQUIRED IN THE SECTION 10(A)PROSPECTUS

ITEM 1. PLAN INFORMATION.*

ITEM 2. REGISTRANT INFORMATION AND EMPLOYEE PLAN ANNUAL INFORMATION.*

*Information required by Part I to be contained in the Section 10(a) prospectus
is omitted from this registration statement in accordance with Rule 428 under
the Securities Act and the Note to Part I of Form S-8.

                                     PART II
               INFORMATION REQUIRED IN THE REGISTRATION STATEMENT

ITEM 3. INCORPORATION OF DOCUMENTS BY REFERENCE.

      The following documents filed with the Securities and Exchange Commission
(the "Commission") are hereby incorporated by reference:

      (a) The registrant's Transition Report on Form 10-K for the transition
period ended December 31, 2005, filed with the Commission on March 3, 2006,
pursuant to Section 13(a) of the Securities Exchange Act of 1934, as amended
(the "Exchange Act").

      (b) All other reports filed pursuant to Section 13(a) or 15(d) of the
Exchange Act since the end of the fiscal period covered by the Transition Report
referred to in (a) above.

      (c) The description of the registrant's Common Stock, par value $.01 per
share, as contained in a registration statement on Form 8-A filed on October 29,
1984, as amended by Form 8-A/A filed on October 15, 1990, including any
amendment or report filed for the purpose of updating such description.

      (d) The description of the registrant's Series B Preferred Stock Purchase
Rights as contained in a registration statement on Form 8-A filed on May 22,
2002, including any amendment or report filed for the purpose of updating such
description.

      All documents subsequently filed by the registrant pursuant to Sections
13(a), 13(c), 14 and 15(d) of the Exchange Act, prior to the filing of a
post-effective amendment which indicates that all securities offered hereby have
been sold or which deregisters all securities then remaining unsold, shall be
deemed to be incorporated by reference in this registration statement and to be
part hereof from the date of filing such documents.

ITEM 4. DESCRIPTION OF SECURITIES.

      Not applicable.

ITEM 5. INTERESTS OF NAMED EXPERTS AND COUNSEL.

      Not applicable.

ITEM 6. INDEMNIFICATION OF DIRECTORS AND OFFICERS.

      Section 145 of the Delaware General Corporation Law (the "DGCL") empowers
a corporation to indemnify any person who was or is a party or is threatened to
be made a party to any threatened, pending or completed action, suit or
proceeding, whether civil, criminal, administrative or investigative (other than
an action by or in the right of the corporation) by reason of the fact that he
or she is or was a director, officer, employee or agent of the corporation or is
or was serving at the request of the corporation as a director, officer,
employee or agent of

                                        1
another corporation or other enterprise, against expenses (including attorneys'
fees), judgments, fines and amounts paid in settlement actually and reasonably
incurred by him or her in connection with such action, suit or proceeding if he
or she acted in good faith and in a manner he or she reasonably believed to be
in, or not opposed to, the best interests of the corporation, and, with respect
to any criminal action or proceeding, had no reasonable cause to believe his or
her conduct was unlawful.

      Section 145 also empowers a corporation to indemnify any person who was or
is a party or is threatened to be made a party to any threatened, pending or
completed action or suit by or in the right of the corporation to procure a
judgment in its favor by reason of the fact that such person acted in any of the
capacities set forth above, against expenses (including attorneys' fees)
actually and reasonably incurred by him or her in connection with the defense or
settlement of such action or suit if he or she acted under similar standards,
except that no indemnification may be made in respect of any claim, issue or
matter as to which such person shall have been adjudged to be liable to the
corporation unless, and only to the extent that, the Delaware Court of Chancery
or the court in which such action was brought shall determine that despite the
adjudication of liability such person is fairly and reasonably entitled to
indemnity, for such expenses which the Delaware Court of Chancery or such other
court shall deem proper.

      Section 145 further provides that to the extent a director, officer,
employee or agent of a corporation has been successful in the defense of any
action, suit or proceeding referred to above or in the defense of any claim,
issue or matter therein, he or she shall be indemnified against expenses
(including attorneys' fees) actually and reasonably incurred by him or her in
connection therewith, that indemnification provided for by Section 145 shall not
be deemed exclusive of any other rights to which the indemnified party may be
entitled; and that the corporation is empowered to purchase and maintain
insurance on behalf of any person who is or was a director, officer, employee or
agent of the corporation against any liability asserted against him or her in
any such capacity or arising out of his or her status as such, whether or not
the corporation would have the power to indemnify him or her against such
liability under Section 145.

      Section 102(b)(7) of the DGCL enables a corporation in its certificate of
incorporation to limit the personal liability of members of its board of
directors for violation of a director's fiduciary duty of care. Article 10 of
the Company's certificate of incorporation, as authorized by Section 102(b)(7),
provides that a director shall not be liable to the Company for breach of a
fiduciary duty, except for liability:

            -     for any breach of the director's duty of loyalty to the
                  Company or the Company's stockholders;

            -     for acts or omissions not in good faith or which involve
                  intentional misconduct or a knowing violation of law;

            -     under section 174 of the DGCL providing for liability of
                  directors for unlawful payment of dividends or unlawful stock
                  purchases or redemptions;

            -     for any transaction from which a director derived an improper
                  benefit; or

            -     for any act or omission occurring prior to the date when
                  Article 10 became effective.

      Section 8.1 of the Company's bylaws provides for the indemnification, to
the fullest extent authorized by law, of any person made, or threatened to be
made, a party to an action or proceeding, whether criminal, civil,
administrative or investigative, against expenses, judgments, fines, and amounts
paid in settlement incurred in connection with such action or proceeding, by
reason of the fact that such person is or was a director or officer of the
Company. The Company's Directors' and Officers' Liability Insurance, which is
provided for under Section 8.3 of the Company's bylaws, insures directors and
officers against any liability arising out of such person's status as a director
or officer, and insures the Company against its obligations to indemnify its
directors and officers.

      Certain of the Company's officers and directors have executed indemnity
agreements which supplement the protections provided by the Company's
certificate of incorporation and bylaws. These agreements require the

                                        2
Company to pay for any damages, judgments, settlements, costs and expenses for
the defense of legal actions, claims, proceedings and appeals due to any actual
or alleged breach of duty, neglect, error, misstatement, misleading statement,
omission or other act done, suffered or wrongfully attempted by the officer or
director. If the Company does not pay such costs and expenses within 90 days
after it receives a written claim, such officers or directors may bring a suit
against the Company to recover the unpaid amount of the claim. If such officer
or director is successful, the Company will be required to pay for the expenses
incurred relating to the claim.

Item 7. EXEMPTION FROM REGISTRATION CLAIMED. Not applicable.

Item 8. EXHIBITS.
Exhibit
Number
4.1      Rights Agreement dated as of May 17, 2002 ("Rights Agreement") between the
         Company and Continental Stock Transfer & Trust Company, as Rights Agent
         (incorporated by reference to exhibit 4.2 to the Company's Form 8-A
         (File No. 000-12957) filed with the Commission on May 22, 2002).

5.1      Opinion of Heller Ehrman LLP.

10.1     2007 Employee Stock Purchase Plan.

23.1     Consent of Heller Ehrman LLP (included in Exhibit 5.1).

23.2     Consent of Independent Registered Public Accounting Firm.

24.1     Powers of Attorney (included in signature page to this registration statement).
Item 9. UNDERTAKINGS.

      (a) The undersigned registrant hereby undertakes:

            (1) To file, during any period in which offers or sales are being
made, a post-effective amendment to this registration statement:

                  (i) To include any prospectus required by Section 10(a)(3) of
the Securities Act;

                  (ii) To reflect in the prospectus any facts or events arising
after the effective date of the registration statement (or the most recent
post-effective amendment thereof) which, individually or in the aggregate,
represent a fundamental change in the information set forth in the registration
statement. Notwithstanding the foregoing, any increase or decrease in volume of
securities offered (if the total dollar value of securities offered would not
exceed that which was registered) and any deviation from the low or high end of
the estimated maximum offering range may be reflected in the form of prospectus
filed with the Commission pursuant to Rule 424(b) if, in the aggregate, the
changes in volume and price represent no more than a 20% change in the maximum
aggregate offering price set forth in the "Calculation of Registration Fee"
table in the effective registration statement; and

                  (iii) To include any material information with respect to the
plan of distribution not previously disclosed in the registration statement or
any material change to such information in the registration statement;

      Provided, however, that paragraphs (a)(1)(i) and (a)(1)(ii) above do not
apply if the information required to be included in a post-effective amendment
by those paragraphs is contained in periodic reports filed with or furnished to
the Commission by the registrant pursuant to Section 13 or Section 15(d) of the
Exchange Act that are incorporated by reference in the registration statement.

                                        3
(2) That, for the purpose of determining any liability under the
Securities Act, each such post-effective amendment shall be deemed to be a new
registration statement relating to the securities offered therein, and the
offering of such securities at that time shall be deemed to be the initial bona
fide offering thereof.

            (3) To remove from registration by means of a post-effective
amendment any of the securities being registered which remain unsold at the
termination of the offering.

      (b) The undersigned registrant hereby undertakes that, for purposes of
determining any liability under the Securities Act, each filing of the
registrant's annual report pursuant to Section 13(a) or Section 15(d) of the
Exchange Act (and, where applicable, each filing of an employee benefit plan's
annual report pursuant to Section 15(d) of the Exchange Act) that is
incorporated by reference in the registration statement shall be deemed to be a
new registration statement relating to the securities offered therein, and the
offering of such securities at that time shall be deemed to be the initial bona
fide offering thereof.

      (c) Insofar as the indemnification for liabilities arising under the
Securities Act may be permitted to directors, officers and controlling persons
of the registrant pursuant to the foregoing provisions, or otherwise, the
registrant has been advised that in the opinion of the Commission such
indemnification is against public policy as expressed in the Securities Act and
is, therefore, unenforceable. In the event that a claim for indemnification
against such liabilities (other than the payment by the registrant of expenses
incurred or paid by a director, officer or controlling person of the registrant
in a successful defense of any action, suit or proceeding) is asserted by such
director, officer or controlling person in connection with the securities being
registered hereunder, the registrant will, unless in the opinion of its counsel
the matter has been settled by controlling precedent, submit to a court of
appropriate jurisdiction the question of whether such indemnification by it is
against public policy as expressed in the Securities Act and will be governed by
the final adjudication of such issue.

                            [Signature Pages Follow]

                                        4
SIGNATURES

      Pursuant to the requirements of the Securities Act of 1933, the registrant
certifies that it has reasonable grounds to believe that it meets all of the
requirements for filing on Form S-8 and has duly caused this Registration
Statement to be signed on its behalf by the undersigned, thereunto duly
authorized, in the City of Bridgewater, State of New Jersey, on January 26,
2007.

                                 Enzon Pharmaceuticals, Inc.

                                 By: /s/ Jeffrey H. Buchalter
                                     --------------------------------------
                                     Jeffrey H. Buchalter
                                     President, Chief Executive Officer and
                                     Chairman of the Board (Principal Executive
                                     Officer)

                                POWER OF ATTORNEY

      KNOW ALL PERSONS BY THESE PRESENTS, that each person whose signature
appears below constitutes and appoints Jeffrey H. Buchalter and Craig A. Tooman,
jointly and severally, his or her attorneys-in-fact and agents, each with the
power of substitution and resubstitution, for him or her and in his or her name,
place or stead, in any and all capacities, to sign any amendments to this
Registration Statement on Form S-8, and to file such amendments, together with
exhibits and other documents in connection therewith, with the Securities and
Exchange Commission, granting to each attorney-in-fact and agent, full power and
authority to do and perform each and every act and thing requisite and necessary
to be done in and about the premises, as fully as he or she might or could do in
person, and ratifying and confirming all that the attorneys-in-fact and agents,
or his or her substitute or substitutes, may do or cause to be done by virtue
hereof.

      Pursuant to the requirements of the Securities Act of 1933, this
Registration Statement has been signed by the following persons in the
capacities and on the dates indicated.
Signature                               Title                              Date
----------------------------  -----------------------------------------------  ----------------
/s/ Craig A. Tooman           Executive Vice President, Finance and Chief      January 26, 2007
---------------------------   Financial Officer (Principal Financial
Craig A. Tooman               Officer)

/s/ Jeffrey H. Buchalter      President, Chief Executive Officer and Chairman  January 26, 2007
---------------------------   of the Board (Principal Executive Officer)
Jeffrey H. Buchalter

/s/ Goran Ando                Director                                         January 26, 2007
---------------------------
Goran Ando

/s/ Rolf A. Classon           Director                                         January 26, 2007
---------------------------
Rolf A. Classon

/s/ Robert LeBuhn             Director                                         January 26, 2007
---------------------------
Robert LeBuhn

/s/ Victor P. Micati          Director                                         January 26, 2007
---------------------------
Victor P. Micati

/s/ Phillip M. Renfro         Director                                         January 26, 2007
---------------------------
Phillip M. Renfro

/s/ Robert C. Salisbury       Director                                         January 26, 2007
---------------------------
Robert C. Salisbury
5
INDEX TO EXHIBITS
Exhibit
Number
5.1    Opinion of Heller Ehrman LLP.

10.1   2007 Employee Stock Purchase Plan.

23.1   Consent of Heller Ehrman LLP (included in Exhibit 5.1).

23.2   Consent of Independent Registered Public Accounting Firm.

24.1   Powers of Attorney (included in signature page to this registration statement).