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CONFIDENTIAL MATERIALS OMITTED AND FILED SEPARATELY WITH THE SECURITIES AND
EXCHANGE COMMISSION. ASTERISKS DENOTE OMISSIONS.

                                                                   EXHIBIT 10.17

                       FIRST AMENDMENT TO SUPPLY AGREEMENT

      THIS FIRST AMENDMENT TO SUPPLY AGREEMENT (the "AMENDMENT") is entered into
as of July 7, 2003 (the "AMENDMENT EFFECTIVE DATE"), between ALGORX
PHARMACEUTICALS, INC., a Delaware corporation ("ALGORX"), and
POWDERJECT TECHNOLOGIES LIMITED, an English corporation ("POWDERJECT"). AlgoRx
and Powderject may be referred to herein individually as a "PARTY" and
collectively as the "PARTIES".

                                    RECITALS

      WHEREAS, AlgoRx and PowderJect entered into a Supply Agreement effective
as of March 22, 2002 (the "SUPPLY AGREEMENT"), pursuant to which PowderJect is
obligated to supply, and AlgoRx is obligated to purchase from PowderJect,
AlgoRx's requirements of Gas Cylinders;

      WHEREAS, PowderJect has been obtaining AlgoRx's requirements of Gas
Cylinders from *** pursuant to the *** Agreements and supplying such cylinder to
AlgoRx; and

      WHEREAS, PowderJect has with AlgoRx's consent entered into a variation of
the *** Agreements; and

      WHEREAS, pursuant to guidelines promulgated by the FDA , AlgoRx will be
required to use, for pre-commercial purposes, certain quantities of Gas
Cylinders Manufactured off a Line, rather than the Pilot Plant; and

      WHEREAS, the parties desire to amend the Supply Agreement, inter alia, to
establish the price that AlgoRx will pay for the supply of Gas Cylinders for
pre-commercial purposes that are manufactured off a Line, to agree to the
minimum order size of Gas Cylinders, to reduce the minimum annual capacity of
the Line, and to clarify the circumstances under which PowderJect shall be
considered the manufacturer of Gas Cylinders for purposes of determining the
Cylinder Cost payable by AlgoRx for Gas Cylinders;

      NOW, THEREFORE, PowderJect and AlgoRx hereby agree that the Supply
Agreement shall be amended, effective as of the Amendment Effective Date, as
provided below;

      1. All capitalized terms used but not otherwise defined herein shall have
the meanings ascribed to such terms in the Supply Agreement.

      2. PowderJect hereby agrees to use its best efforts to achieve the
successful completion of all tests and procedures for the commissioning of the
first Line as soon as reasonably practicable. PowderJect understands and
acknowledges that after such Commissioning Date, AlgoRx may require that Gas
Cylinders for use in or with Devices for pro-commercial use be Manufactured off
a Line rather than the Pilot Plant. AlgoRx shall notify PowderJect in its
forecasts provided under Section 2.4(a) and in purchase orders provided to
PowderJect under Section 2.5(a) of the Supply Agreement of the quantity of Gas
Cylinders for pre-commercial use that shall be Manufactured off a Line.
PowderJect shall ensure that all such Gas Cylinders ordered by AlgoRx shall be
Manufactured off a Line rather than the Pilot plant and supplied to AlgoRx in
accordance with the applicable purchase order. The warranty in



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Section 6.2 shall apply to all Gas Cylinders for pre-commercial use that are
Manufactured off a Line and supplied to AlgoRx hereunder.

      3.    "OPERATING COSTS" has the meaning set forth in the ***** Agreement.

      4.    Section 1.5 of the Supply Agreement shall be deleted and replaced
with the following new Section 1.5:

      "1.5 "*** AGREEMENTS" means: (a) the Services, Manufacture and Supply
      Agreement made between PowderJect and *** ****** dated 21st February
      2003, (h) the Warranty, Spare Parts, Service and Maintenance and Software
      Agreement made between PowderJect, *** ***** ********** ******* ***,
      and *** ****** dated 21st February 2003, (c) the Asset Transfer Agreement
      made between PowderJect and *** ****** dated 21st February 2003, and (d)
      amendments to any of the agreements set forth in subclauses (a) through
      (c) that are entered into by ***** and PowderJect after the Amendment
      Effective Date with AlgoRx's written consent."

      5.    Section 1.12 of the Supply Agreement shall be deleted and replaced
with the following new Section 1.12:

      "1.12 "CYLINDER COST" means the following:

            (a) For so long as the ***** Agreement is in effect and is not
      amended in a manner that impacts PowderJect's costs and expenses related
      to the manufacture of Gas Cylinders thereunder, "Cylinder Cost" means the
      per cylinder cost of Gas Cylinders for commercial use that are
      Manufactured off a Line and supplied to AlgoRx by PowderJect, which shall
      be equal to the sum of (i) and (ii) below, divided by ********.

                  (i) Operating Costs (but excluding, for clarity, (A) any costs
            or expenses relating to the operation and maintenance of the Pilot
            Plant or the Manufacture of Gas Cylinders off the Pilot Plant, and
            (B) Operating Costs associated with the supply of Gas Cylinders by
            ***** to third parties in accordance with Clause 10.4 of the *****
            Agreement) and the applicable Gas Cylinder Price and Annual
            Management Fee (as defined in the ***** Agreement) payable by
            PowderJect under the terms of the ***** Agreement; and

                  (ii) the costs payable by PowderJect under the Warranty, Spare
            Parts, Service and Maintenance and Software Agreement made between
            PowderJect, *** ***** ********** ******* *** and *** *******
            dated 21st February 2003.

      For the avoidance of doubt, capital costs, depreciation of machinery,
      systems , and equipment required for the Manufacture of Gas Cylinders,
      corporate overhead

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      (such as administrative expenses) shall not be included as part of, or
      considered in determining, the Cylinder Cost.

            (b) If the ***** Agreement either is terminated or is amended in a
      manner that negatively impacts PowderJect's costs and expenses related to
      the manufacture of Gas Cylinders thereunder, "Cylinder Cost" shall mean
      the per cylinder cost of Gas Cylinders Manufactured off a Line and
      supplied to AlgoRx, which shall be determined based on the sum of the
      following costs actually incurred by PowderJect, to the extent reasonably
      allocable to the Manufacture of Gas Cylinders supplied to AlgoRx:(i)
      PowderJect's cost of direct materials; (ii) direct labor costs; and (iii)
      fixed and variable overhead costs for that portion of the utilities and
      rent for manufacturing facilities directly allocable to the Manufacture of
      Gas Cylinders for AlgoRx; in each case to the extent reasonably allocated
      to the Gas Cylinders based on production activity. Any capital costs,
      depreciation of specific machinery, systems and equipment required
      for the Manufacture of Gas Cylinders, and corporate overhead (such as
      administrative expenses) shall not be considered in determining the
      Cylinder Cost. Cylinder Cost shall be calculated in a manner consistent
      with Generally Accepted Accounting Principles consistently applied, and
      the methodology used in making the allocations referred to above shall be
      consistent with PowderJect's methodology for other similar products and
      shall be consistent from year to year. PowderJect shall disclose such
      methodology to AlgoRx upon request.

      6.    Section 1.24 of the Supply Agreement shall be deleted in its
      entirety and replaced with the following new Section 1.24:

      "1.24 "LINE" means all of the plant, machinery, systems, and other
      equipment that is necessary to Manufacture Gas Cylinders in accordance
      with the Gas Cylinder Specification and package them in accordance with
      the Packaging Specification, which has a minimum annual capacity
      significantly greater than that of the Pilot Plant, but in no event less
      than a minimum annual capacity of ***** Gas Cylinders.
      Notwithstanding the foregoing, the first Line commissioned and validated
      under the ***** Agreements shall have a minimum annual capacity of
      approximately ***** Gas Cylinders. However, each additional Line
      shall have an annual capacity of at least ***** Gas Cylinders."

      7.    Section 1.30 of the Supply Agreement shall be deleted in its
      entirety and replaced with the following new Section 1.30:

      "1.30 "PILOT PLANT CYLINDER COST" means ***** per Gas Cylinder."

      8.    Section 2.2 of the Supply Agreement shall be deleted in its entirety
      and replaced with the following new Section 2.2:

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      "2.2 SC SUBCOMMITTEE REPRESENTATION. Promptly after the Amendment,
      Effective Date, PowderJect shall appoint an individual designated by
      AlgoRx who is reasonably acceptable to PowderJect to the gas cylinder
      Sublicensee subcommittee ("SC Subcommittee") organized under the
      provisions of clause 6.4 of the **** Agreement. In addition, PowerJect
      shall provide reasonable advance notice to AlgoRx of all scheduled
      meetings of the SC Subcommittee with **** regarding the Gas Cylinder
      Specification, the Packaging Specification, Line Construction, the
      specifications for Lines the Budget (as defined in the **** Agreement) and
      any amendments thereto, and quality control issues, and AlgoRx shall have
      the right to amend all such meetings. AlgoRx shall bear its own expenses
      related to attending each SC Subcommittee meeting."

      9. The following two sentences shall be inserted after the first sentence
      of Section 2.5 of the Supply Agreement:

      "All purchase order submitted by AlgoRx hereunder shall be in multiples of
      **** Gas Cylinders, and the minimum order size that PowderJect shall be
      required to accept shall be **** Gas Cylinders,"

      10. The first sentence of Section 2.8 of the Supply Agreement shall be
      deleted and replaced with the following new sentences:

      "Shipments will be FCA ([ILLEGIBLE] 2000) Leatherhead, UK or such other
      location in the UK as PowderJect shall reasonably specify, by a common
      carrier selected by AlgoRx."

      11.   SECTION 5.1 of the Supply Agreement shall be deleted in its
      entirety and replaced with the following new Section 5.1:

      "5.1 PAYMENT. AlgoRx shall pay PowderJect the price set forth in this
      Section 5.1 for each Gas Cylinder supplied to AlgoRx under this Agreement,
      as such price may be adjusted, if applicable, in accordance with Section
      5.2.

            (a) PILOT PLANT PRICE. For each Gas Cylinder ordered by AlgoRx in
      accordance with Sections 2.4(a) and 2.5(a) and Manufactured off the Pilot
      Plant, AlgoRx shall pay PowderJect the Pilot Plant Cylinder Cost, plus the
      reasonable costs of packaging, transport, including handling charges,
      insurance, and any applicable governmental taxes or duties (including,
      without limitation, any valued added taxes or sales taxes). The costs of
      packaging shall not include any share of the capital costs relating to
      packaging equipment.

            (b) PRE-COMMERCIAL LINE PRICE. For Gas Cylinders ordered by AlgoRx
      in accordance with Sections 2.4(a) and 2.5(a) and Manufactured off a Line,
      AlgoRx shall pay PowderJect a price of **** per Gas Cylinder (the
      "Pre-Commercial Cylinder Line Price"), plus the reasonable costs of
      packaging.

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      (c) LINE PRICE. For each Gas Cylinder ordered by AlgoRx in accordance with
Sections 2.4(b) and 2.5(b), AlgoRx shall pay PowderJect the Cylinder Cost (if
PowderJect Manufactured such Gas Cylinder) or the actual amount of PowderJect's
out-of-pocket cost of procuring Gas Cylinders from a Third Party Manufacturer
(the price payable by AlgoRx, the "Line Price"), plus the reasonable costs of
packaging, transport, including handling charges, insurance, and any applicable
governmental taxes or duties (including, without limitation, any valued added
taxes or sales taxes). The cases of packaging shall not include any share of the
capital costs relating to packaging equipment. Except as set forth in Section
5.2, the Line Price of Gas Cylinders shall not exceed **** per Gas Cylinder (the
"Capped Price") The Parties acknowledge and agree that the Line Price is
expected to decrease as the volume of Gas Cylinders being Manufactured
increases. In the event that PowderJect is Manufacturing Gas Cylinders for
supply to AlgoRx, PowderJect acknowledges and agrees that it shall be obligated
to use best efforts to run all Lines as efficiently as possible in order to
reduce the Cylinder Cost. If PowderJect is Manufacturing Gas Cylinders, the
Cylinder Cost for the first twelve (12) months that PowderJect is Manufacturing
such cylinders (the "Initial Production Period") shall be the Capped Price.
After the Initial Production Period, PowderJect shall be in a position to
establish the actual cost of Manufacture of such Gas Cylinders. If the actual
Cylinder Cost upon the expiration of the Initial Production Period is less than
the Capped Price, PowderJect shall promptly reimburse AlgoRx for its overpayment
for Gas Cylinders during the Initial Production Period. Notwithstanding the
foregoing, if at any time during the term of this Agreement the Line Price at
which PowderJect is supplying Gas Cylinders to AlgoRx is less than PowderJect's
actual Cylinder Cost or out-of-pocket cost due to the Capped Price (such
differences, the "Loss"), then PowderJect shall be obligated to reimburse AlgoRx
for overpayment for Gas Cylinders during the Initial Production Period only to
the extract that the amount of such overpayment is greater than PowderJect's
aggregate loss during such period, and PowderJect may continue to charge AlgoRx
the Capped Price for each Gas Cylinder after the Initial Production Period even
if the Line Price is subsequently less than the Capped Price, until PowderJect
has recovered the full amount of its Loss.

      (d) INVOICE AND PAYMENT. PowderJect shall invoice AlgoRx for each shipment
of Gas Cylinders delivered to AlgoRx, and AlgoRx shall pay such invoice not
later than twenty-five (25) days after delivery of the applicable Gas Cylinders.
Notwithstanding the foregoing, if AlgoRx rejects any Gas Cylinders in good
faith pursuant to Section 3.3(a) or Section 3.3(b), AlgoRx shall have no payment
obligation to powderJect with respect to such Gas Cylinders unless and until any
such Gas Cylinders have been replaced pursuant to Section 3.3(c) or any dispute
regarding whether such Gas Cylinders are defective is resolved in PowderJect's
favor pursuant to Section 3.3(d). For Gas Cylinders for commercial use supplied
to AlgoRx, PowderJect shall estimate the Cylinder Cost using the Operating Costs
set forth in the current Budget (as defined in the **** Agreement), and shall
invoice AlgoRx for such estimated Cylinder Cost

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multiplied by the number of Gas Cylinders in each shipment (the "Estimated
Cylinder Cost). By April 30 of each calendar year, PowderJect shall provide
AlgoRx with a written report setting forth (i) the actual Operating Costs for
the proceding 12-month period from April 1 through March 31, (ii) the number of
Gas Cylinders supplied to AlgoRx during such 12-month period, and (iii) the
actual Cylinder Cost for such Gas Cylinders. If the Estimated Cylinder Cost
paid by AlgoRx for such Gas Cylinders exceeds the actual Cylinder Cost for such
Gas Cylinders, PowderJect shall pay AlgoRx the difference between such amounts
at the time that it provides the annual written report to AlgoRx. If the
Estimated Cylinder Cost paid by AlgoRx for such Gas Cylinders is less than the
actual Cylinder Cost for such Gas Cylinders, AlgoRx shall pay PowderJect the
differences between such amounts within thirty (30) days after AlgoRx's receipt
from PowderJect of the annual written report."

12. The fourth sentence of Section 10.1 of the Agreement shall be amended by
deleting the word "PowderJect where it appears in such sentence between the
words "the occurrence of a force majeuro event" and "shall have the right to
seek an order", and inserting in its place the word "AlgoRx".

13. For so long as the ***** Agreement is in effect, PowderJect shall be
considered to be the Manufacturer of Gas Cylinder for commercial use supplied to
AlgoRx for purposes of determining the Line Price, and accordingly AlgoRx shall
pay PowderJect the Cylinder Cost for such Gas Cylinders. If PowderJect amends
the ***** Agreement or enters into a Third Party Manufacturer Agreement as
permitted under the Supply Agreement, then for purposes of determining the Line
Price payable under the Supply Agreement by AlgoRx for Gas Cylinders
manufactured under such amended ***** Agreement or Third Party Manufacturer
Agreement, PowderJect shall be deemed to have Manufactured such Gas Cylinders
and the Cylinder Cost shall be the Line Price if PowderJect and/or its
Affiliates either (a) owns more than ***** ******* of the packaging and other
related machinery, equipment, fixtures, and fittings comprising the Line, or (b)
pays more than ***** ******* of the expenses of operating and maintaining the
Line.

14. Except as amended hereby, the Agreement shall remain in full force and
effect.

15. This Amendment may be executed in one or more counterparts, each of which
shall be an original, and all of which shall constitute together the same
document.

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      IN WITNESS WHEREOF, the Parties have caused this Amendment to be executed.

ALGORX PHARMACEUTICALS, INC.           POWDERJECT TECHNOLOGIES LIMITED

By: /s/ Gordon M. Saul                 By: /s/ C. S. W. Swingland
   -------------------------              -----------------------------

Name: Gordon M. Saul                   Name: C. S. W. Swingland

Title: Vice President                  Title: Director

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