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                                                                   EXHIBIT 10.23

[ALGORX PHARMACEUTICALS, INC. LOGO]

September 16, 2004

Paul Hamelin
8369 Santaluz Village Green East
San Diego CA 92127

Dear Paul:

AlgoRx Pharmaceuticals, Inc. is pleased to offer you a position of President and
Chief Operating Officer starting on or before September 27, 2004. In this
position you will be reporting to Ronald M. Burch, President and Chief Executive
Officer, and will be working out of our corporate office in Secaucus, NJ.

The base salary offered for this exempt position is $12,500 per pay period (bi-
weekly pay cycle) and an Annual performance bonus of up to 40% (cash and/or a
grant of stock options at Board of Directors' discretion) payable, January 2005.
We also wish to extend a signing bonus of $100,000, of which $50,000 will be
rendered to you within the first pay period after commencing employment, and the
remainder based on the achievement of mutually agreed upon milestone(s) on June
1, 2005. This offer is not to be considered a contract guaranteeing employment
for any specific duration and is contingent on the signing of a confidentiality
agreement. As an at-will employee, both you and the Company have the right to
terminate your employment at any time. Should the company terminate your
employment for any reason other than "for cause" (see definition of "cause"
below) you will be eligible for severance consisting of your base salary for
twelve months, with continued vesting of your stock option grant for twelve
months.

On your first day of employment, we will provide additional information about
the objectives and policies, benefit programs, general employment conditions and
completion of employment and benefit forms. To fulfill federal identification
requirements, you should bring documentation to support your identity and
eligibility to work in the United States. The types of acceptable documentation
are listed on the Form I-9 of the Immigration and Naturalization Service
enclosed in the original offer letter. Please feel free to contact Debra Hopper
if you have any questions about which documents are acceptable to verify your
identity and eligibility to work in the United States.

Because you will play an important role in the operations and development of
AlgoRx, we would like to offer you the award of 5,250,000 shares of AlgoRx
common stock (equivalent to approximately 3% of the currently outstanding
shares), subject to the approval of the Company's Board of Directors. (Note that
the Board of Directors will need to approve a small increase in the total
outstanding shares to account for obligations, hence the term "approximately.")
These shares would be made available to you at the fair market value set by the
board of directors at its September 29, 2004 meeting, 25% on the first
anniversary of your employment, then 1/36th of the remaining shares pro rata
each month for three years (total vesting time, four years); provided, that all
options granted hereunder shall vest immediately if there is a (i) "change of
control" of the Company and (ii) your employment is thereafter terminated
without "cause" or "constructively terminated" within the twelve month period
following the change of control. For purposes of this agreement, "change of
control" shall mean (i) a sale of substantially all of the assets of the
Company; (ii) a merger or consolidation in which the Company is not the
surviving

                500 Plaza Drive, Second Floor, Secaucus NJ 07094
                                  201-325-6900

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corporation (other than merger or consolidation in which the Company
shareholders immediately before the merger or consolidation have, immediately
after the merger or consolidation, own greater than a majority of the stock
voting power of the successor corporation); or (iii) any transaction or series
of related transactions in which in excess of fifty percent (50%) of the
Company's voting power is transferred, other than sale by the Company of stock
in transactions the primary purpose of which is to raise capital for the
Company's operations and activities.

In addition, "cause" shall mean misconduct, including: (i) conviction of any
felony or crime involving moral turpitude or dishonesty; (ii) participation in a
fraud or act of dishonesty against the Company; (iii) willful and material
breach of your employment agreement; intentional and material damage to the
Company's property or (v) material breach of the Proprietary Information and
Inventions Agreement or any employee policy of the Company. "Constructive
termination" shall mean any of the following actions taken without Cause by the
Company or a successor corporation or entity without your consent; (i)
substantial reduction of your rate of compensation other than in connection with
reductions to the rate of compensation of all officers; (ii) material reduction
in your duties, provided, however, that a change in job position (including a
change in title) shall not be deemed a "material reduction" unless your new
duties are substantially reduced from the prior duties; or (iii) relocation of
your principal place of employment to a place greater than 50 miles from your
then current principal place of employment.

You will have ten years in which to exercise the options from the date such
options vest. I would like to emphasize at present, the stock of AlgoRx is not
liquid.

We hope that you will accept this offer and look forward to you joining AlgoRx
and playing a major role in building AlgoRx into the preeminent analgesics
company.

Sincerely,

/s/ Ronald M. Burch
-------------------------------------
Ronald M. Burch, M.D., Ph.D.
President and Chief Executive Officer

cc: D. W. Hopper

Please indicate your acceptance by your signature and return this offer letter
to me at your earliest convenience. Thank you.

/s/ Paul Hamlin                                   9/16/2004
----------------------                         ----------------------
 Signature                                          Date

                500 Plaza Drive, Second Floor, Secaucus NJ 07094
                                  201-325-6900<PAGE>

                                                                   EXHIBIT 10.24

[ALGORX PHARMACEUTICALS, INC. LOGO]

      June 27, 2002

      Jeffrey D. Lazar, M.D., Ph.D.
      40 Apple Valley Road
      Stamford CT 06903

      Dear Jeffrey:

      AlgoRx Pharmaceuticals, Inc. (the "Company" or "AlgoRx") is pleased to
      offer you a position as Senior Vice President, Clinical Research &
      Regulatory Affairs, ON the terms set forth herein.

            1.    DUTIES: in this position you will report to, and your duties
                  and responsibilities will be determined by, the Chief
                  Executive Officer of the Company. This offer is for a full
                  time position, located at 40 Apple Valley Road, Stamford CT,
                  except as travel to other locations may be necessary to
                  fulfill your responsibilities. Of course, the Company may
                  change your position, duties and work location from time to
                  time as it deems necessary.

            2.    SALARY: Your base salary will be $20,833.33 per month
                  ($250,000 annually), payable in accordance with the Company's
                  customary payroll practice as in effect from time to time.

            3.    BONUS: You will be eligible to earn an annual bonus of up to
                  25% of your annual salary, the exact amount of which will be
                  determined in good faith by the Company's Board of Directors
                  (the "Board"), based on the achievement of objectives
                  established by the Board after consultation with you and
                  provided you remain employed by the Company throughout the
                  applicable bonus year (the "Bonus"). The Bonus shall be
                  payable in cash, stock and/or stock options, in the sole
                  discretion of the Board.

            4.    BENEFITS; TRAVEL: You will receive the Company's standard
                  employee benefits package, as such package is in effect from
                  time to time. You will receive four weeks per calendar year of
                  vacation time, subject to the Company's vacation policy. In
                  addition, the Company will provide and pay for your personal
                  malpractice insurance policy in addition to the clinical
                  trials insurance and directors and officers liability
                  insurance carried by the Company. The Company may modify
                  compensation and benefits from time to time as it deems
                  necessary. In addition to and not in lieu of any other policy
                  that the Company may have on business travel, it is agreed
                  that in case of international and coast-to-coast U.S. domestic
                  air travel, the Company shall pay the cost of "business" class
                  for your travel.

            5.    STOCK OPTIONS: Subject to the approval of the Company's Board
                  of Directors, AlgoRx will grant to you options to purchase
                  905,000 shares of the Company's Common Stock (equal to 2.0%
                  of the Company's outstanding

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      Jeffrey D. Lazar, M.D., Ph.D
      June 27, 2002
      Page 2

                  Common Stock after the closing of the second tranche of the
                  Series B preferred Stock)(the "Options") exercisable at a
                  price of $0,15 per share. The Options will be evidenced by and
                  subject to the terms of a stock option grant notice and stock
                  option agreement, a copy of which will be provided to you
                  separately upon grant, and will vest as follows: (a)
                  Twenty-Five Percent (25%) thereof (or 226,250 shares) on the
                  date that is one (1) year after the commencement of your
                  employment, and (b) the remainder at the rate of
                  One-Thirty-Sixth (1/36) (or 18,1854.17 shares) on the first
                  (1st) day of each successive month thereafter; provided, that
                  all options granted hereunder shall vest immediately if there
                  is a (i) "change of control" of the Company and (ii) your
                  employment is thereafter terminated without "cause" or
                  "constructively terminated" within the twelve month period
                  following the change of control. For purposes of this
                  agreement, "change of control" shall mean (i) a sale of
                  substantially all of the assets of the Company; (ii) a merger
                  or consolidation in which the Company is not the surviving
                  corporation (other than merger or consolidation in which the
                  Company shareholders immediately before the merger or
                  consolidation have, immediately after the merger or
                  consolidation, own greater than a majority of the stock voting
                  power of the successor corporation); or (iii) any transaction
                  or series of related transactions in which in excess of fifty
                  percent (50%) of the Company's voting power is transferred,
                  other than sale by the Company of stock in transactions the
                  primary purpose of which is to raise capital for the Company's
                  operations and activities.

      In addition, "cause" shall mean misconduct, including: (i) conviction of
      any felony or crime involving moral turpitude or dishonesty; (ii)
      participation in a fraud or act of dishonesty against the Company; (iii)
      willful and material breach of your employment agreement; intentional and
      material damage to the Company's property or (v) material breach of the
      Proprietary Information and Inventions Agreement or any employee policy of
      the Company. "Constructive termination" shall mean any of the following
      actions taken without Cause by the Company or a successor corporation or
      entity without your consent; (i) substantial reduction of your rate of
      compensation other than in connection with reductions to the rate of
      compensation of all officers; (ii) material reduction in your duties,
      provided, however, that a change in job position (including a change in
      title) shall not be deemed a "material reduction" unless your new duties
      are substantially reduced from the prior duties; or (iii) relocation of
      your principal place of employment to a place greater than 50 miles from
      your then current principal place of employment.

      The grant of Options shall be in addition to, and not in lieu of, any
      other stock options granted you by the Company (including but not limited
      to those evidenced by AlgoRx Pharmaceuticals, Inc. Stock Option Grant
      notice (AlgoRx Pharmaceuticals, Inc. 2001 Equity Incentive Plan) dated
      November 28, 2001.

            6.    RULES AND REGULATIONS: As an AlgoRx employee, you will be
                  expected to abide by Company rules and policies and sign and
                  comply with the attached Proprietary Information and
                  inventions Agreement which prohibits unauthorized use or
                  disclosure of AlgoRx's proprietary information.

            7.    PROPRIETARY INFORMATION: In your work for the Company, you
                  will be expected not to use or disclose any confidential
                  information, including trade secrets of any former employer or
                  other person to whom you have an

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      Jeffrey D. Lazar, M.D., Ph.D
      June 27, 2002
      Page 3

                  Obligation of confidentiality. Rather, you will be expected to
                  use only that information which is generally known and used by
                  persons with training and experience comparable to your own,
                  which is common knowledge in this industry or otherwise
                  legally in the public domain, or which is otherwise provided
                  or developed by the Company. During our discussions about your
                  job duties, you assured us that you would be able to perform
                  these duties within the guidelines just described.

      You agree that you will not bring onto Company premises arty unpublished
      documents or property belonging to any former employer or other person to
      whom you have an obligation of confidentiality.

            8.    OUTSIDE ACTIVITIES: During your employment with AlgoRx, you
                  will devote your best efforts and attention to the business of
                  AlgoRx. The Company acknowledges and agrees, however, that
                  nothing in this letter shall be deemed to prevent you from
                  engaging in any professional activity outside of your duties
                  hereunder, provided the same: (i) do not materially interfere
                  with performance of your duties hereunder; and (ii) are not a
                  breach of any of the foregoing restrictions on confidential
                  information. The CEO may rescind his consent to these other
                  activities if he determines that such activities materially
                  compromise the Company's business interests.

            9.    TERMINATION: You may terminate your employment with AlgoRx at
                  any time and for any reason whatsoever simply by notifying
                  AlgoRx in writing. Likewise, AlgoRx may terminate your
                  employment at any time, with or without cause or advance
                  notice. Upon such termination, you shall be entitled to all
                  salary, bonus, benefits, and cost reimbursement earned,
                  accrued, granted or incurred up to the date of such
                  termination.

            10.   ENTIRE AGREEMENT: This letter, together with your Proprietary
                  Information and Inventions Agreement, forms the complete and
                  exclusive statement of your employment agreement with AlgoRx.
                  It supercedes any other agreements or promises made to you by
                  anyone, whether oral or written, and it can only be modified
                  in a written agreement signed by an officer of AlgoRx.

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      Jeffrey D. Lazar, M.D., Ph.D.
      June 27, 2002
      Page 4

      We are excited to have you join us and look forward to working with you.

                                        ALGORX PHARMACEUTICALS, INC.

                                        By: /s/ Ronald M. Burch
                                            -----------------------------------
                                            Ronald M. Burch, M.D., Ph.D.
                                            President & Chief Executive Officer

      ACCEPTED AND AGREED:

      /s/ Jeffrey D. Lazar
      -----------------------------
      Jeffrey D. Lazar, M.D., Ph.D.

      Date signed: 29 June 02

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