<PAGE>

                                                                    EXHIBIT 10.7
                                                   [With Acceleration Provisions
                                                         Upon Change of Control]

                          ALGORX PHARMACEUTICALS, INC.

                    EARLY EXERCISE STOCK PURCHASE AGREEMENT

      This EARLY EXERCISE STOCK PURCHASE AGREEMENT (the "Agreement") is made as
of the____day of_____________, 200___, by and between ALGORX PHARMACEUTICALS,
INC., a Delaware corporation (the "Company"), and ____________________________
("Purchaser").

      WHEREAS, the Company has previously granted to the Purchaser options (the
"Options") to purchase Common Stock of the Company;

      WHEREAS, the Stock Option Grant Notice (the "Grant Notice") and the Stock
Option Agreement related to such Options permit the early exercise of the
Options;

      WHEREAS, the Purchaser has elected to early exercise of all or a part of
such Options for a specified number of shares of Common Stock (the "Stock") set
forth on the signature page hereto, on the terms and conditions hereinafter set
forth;

      NOW, THEREFORE, IT IS AGREED between the parties as follows:

      1. VOTING OF STOCK. Purchaser hereby agrees that at every meeting of the
stockholders of the Company, and at every adjournment thereof, and on every
action or approval by written consent of the stockholders of the Company, the
Purchaser will vote its Stock on the same proportionate basis as the votes
actually made on account of all other shares of capital stock of the Company
voted.

      2. REPURCHASE OPTION.

            (a) In the event Purchaser's relationship with the Company (or a
parent or subsidiary of the Company) terminates for any reason (including death
or disability), or for no reason, with or without cause, such that after such
termination Purchaser is no longer an employee of, or consultant to, the Company
(and regardless of whether or not Purchaser is then serving as a director of the
Company), then the Company shall have an irrevocable option (the "Repurchase
Option"), for a period of ninety (90) days after said termination, or such
longer period as may be agreed to by the Company and the Purchaser, to
repurchase from Purchaser or Purchaser's personal representative, as the case
may be, at the original exercise price per share paid by Purchaser for such
Stock ("Option Price"), up to but not exceeding the number of shares of Stock
that have not vested in accordance with the provisions of Sections 2(b) below as
of such termination date.

            (b) One hundred percent (100%) of the Stock shall initially be
subject to the Repurchase Option. Subject to the provisions of Section 5 hereof,
on the date one (1) year from the Vesting Commencement Date (as set forth on the
Grant Notice) (the "Vesting Anniversary Date") twenty-five percent (25%) of the
Stock subject to the Repurchase Option shall vest and be released from the
Repurchase Option. Thereafter,

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1/48th of the Stock shall vest and be released from the Repurchase Option on a
monthly basis measured from the Vesting Anniversary Date, until all the Stock is
released from the Repurchase Option (provided in each case that Purchaser
remains an employee of, or a consultant to, the Company (or a parent or
subsidiary of the Company) as of the date of such release).

      3. EXERCISE OF REPURCHASE OPTION. The Repurchase Option shall be exercised
by written notice signed by an officer of the Company or by any assignee or
assignees of the Company and delivered or mailed as provided in Section 16(a).
Such notice shall identify the number of shares of Stock to be purchased and
shall notify Purchaser of the time, place and date for settlement of such
purchase, which shall be scheduled by the Company within the term of the
Repurchase Option set forth in Section 2(a) above. The Company shall be entitled
to pay for any shares of Stock purchased pursuant to its Repurchase Option at
the Company's option in cash or by offset against any indebtedness owing to the
Company by Purchaser (including without limitation any Note given in payment for
the Stock), or by a combination of both. Upon delivery of such notice and
payment of the purchase price in any of the ways described above, the Company
shall become the legal and beneficial owner of the Stock being repurchased and
all rights and interest therein or related thereto, and the Company shall have
the right to transfer to its own name the Stock being repurchased by the
Company, without further action by Purchaser.

      4. ADJUSTMENTS TO STOCK. If, from time to time, during the term of the
Repurchase Option there is any change affecting the Company's outstanding Common
Stock as a class that is effected without the receipt of consideration by the
Company (through merger, consolidation, reorganization, reincorporation, stock
dividend, dividend in property other than cash, stock split, liquidating
dividend, combination of shares, change in corporation structure or other
transaction not involving the receipt of consideration by the Company), then any
and all new, substituted or additional securities or other property to which
Purchaser is entitled by reason of Purchaser's ownership of Stock shall be
immediately subject to the Repurchase Option and be included in the word "Stock"
for all purposes of the Repurchase Option with the same force and effect as the
shares of the Stock presently subject to the Repurchase Option, but only to the
extent the Stock is, at the time, covered by such Repurchase Option. While the
total Option Price shall remain the same after each such event, the Option Price
per share of Stock upon exercise of the Repurchase Option shall be appropriately
adjusted.

      5. CORPORATE TRANSACTION. In the event of (a) a sale of substantially all
of the assets of the Company; (b) a merger or consolidation in which the Company
is not the surviving corporation (other than a merger or consolidation in which
shareholders immediately before the merger or consolidation have, immediately
after the merger or consolidation, greater stock voting power); or (c) a reverse
merger in which the Company is the surviving corporation but the shares of the
Company's common stock outstanding immediately preceding the merger are
converted by virtue of the merger into other property, whether in the form of
securities, cash or otherwise (other than a reverse merger in which shareholders
immediately before the merger have, immediately after the merger, greater stock
voting power); or (d) 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 the sale by the Company of stock in transactions the primary purpose
of

                                        2
<PAGE>

which is to raise capital for the Company's operations and activities, then the
Repurchase Option shall immediately terminate and all unvested Stock shall
immediately vest.

      6. TERMINATION OF REPURCHASE OPTION. Sections 2, 3 and 4 of this Agreement
shall terminate upon the exercise in full or expiration of the Repurchase
Option, whichever occurs first.

      7. ESCROW OF UNVESTED STOCK. As Security for Purchaser's faithful
performance of the terms of this Agreement and to insure the availability for
delivery of Purchaser's Stock upon exercise of the Repurchase Option herein
provided for, Purchaser agrees, at the closing hereunder, to deliver to and
deposit with the Secretary of the Company or the Secretary's designee ("Escrow
Agent"), as escrow agent in this transaction, three (3) stock assignments duly
endorsed (with date and number of shares blank) in the form attached hereto as
Exhibit A, together with a certificate or certificates evidencing all of the
Stock subject to the Repurchase Option; said documents are to be held by the
Escrow Agent and delivered by said Escrow Agent pursuant to the Joint Escrow
Instructions of the Company and Purchaser set forth in Exhibit B attached hereto
and incorporated by this reference, which instructions shall also be delivered
to the Escrow Agent at the closing hereunder. Purchaser hereby acknowledges that
the Secretary of the Company, or the Secretary's designee, is so appointed as
the escrow holder with the foregoing authorities as a material inducement to
make this Agreement and that said appointment is coupled with an interest and is
accordingly irrevocable. Purchaser agrees that Escrow Agent shall not be liable
to any party hereof (or to any other party). Escrow Agent may rely upon any
letter, notice or other document executed by any signature purported to be
genuine and may resign at any time. Purchaser agrees that if the Secretary of
the Company, or the Secretary's designee, resigns as Escrow Agent for any or no
reason, the Board of Directors of the Company shall have the power to appoint a
successor to serve as Escrow Agent pursuant to the terms of this Agreement.
Purchaser agrees that if the Secretary of the Company resigns as Secretary, the
successor Secretary shall serve as Escrow Agent pursuant to the terms of this
Agreement.

      8. RIGHTS OF PURCHASER. Subject to the provisions of Sections 1, 9, 12 and
14 herein, Purchaser shall exercise all rights and privileges of a shareholder
of the Company with respect to the Stock deposited in escrow. Purchaser shall be
deemed to be the holder for purposes of receiving any dividends that may be paid
with respect to such shares of Stock, even if some or all of such shares of
Stock have not yet vested and been released from the Repurchase Option.

      9. LIMITATIONS ON TRANSFER. In addition to any other limitation on
transfer created by applicable securities laws, Purchaser shall not assign,
hypothecate, donate, encumber or otherwise dispose of any interest in the Stock
while the Stock is subject to the Repurchase Option. After any Stock has been
released from the Repurchase Option, Purchaser shall not assign, hypothecate,
donate, encumber or otherwise dispose of any interest in the Stock except in
compliance with the provisions herein and applicable securities laws.
Furthermore, the Stock shall be subject to any right of first refusal in favor
of the Company or its assignees that may be contained in the Company's Bylaws.

                                        3
<PAGE>

      10. RESTRICTIVE LEGENDS. All certificates representing the Stock shall
have endorsed thereon legends in substantially the following forms (in addition
to any other legend which may be required by other agreements between the
parties hereto):

            (a) "THE SHARES REPRESENTED BY THIS CERTIFICATE ARE SUBJECT TO AN
OPTION SET FORTH IN AN AGREEMENT BETWEEN THE COMPANY AND THE REGISTERED HOLDER,
OR SUCH HOLDER'S PREDECESSOR IN INTEREST, A COPY OF WHICH IS ON FILE AT THE
PRINCIPAL OFFICE OF THE COMPANY. ANY TRANSFER OR ATTEMPTED TRANSFER OF ANY
SHARES SUBJECT TO SUCH OPTION IS VOID WITHOUT THE PRIOR EXPRESS WRITTEN CONSENT
OF THE COMPANY."

            (b) "THE SHARES REPRESENTED BY THIS CERTIFICATE HAVE NOT BEEN
REGISTERED UNDER THE SECURITIES ACT OF 1933 AS AMENDED. THEY MAY NOT BE SOLD,
OFFERED FOR SALE, PLEDGED OR HYPOTHECATED IN THE ABSENCE OF AN EFFECTIVE
REGISTRATION STATEMENT AS TO THE SECURITIES UNDER SAID ACT OR AN OPINION OF
COUNSEL SATISFACTORY TO THE COMPANY THAT SUCH REGISTRATION IS NOT REQUIRED."

            (c) "THE SHARES REPRESENTED BY THIS CERTIFICATE ARE SUBJECT TO A
RIGHT OF FIRST REFUSAL OPTION IN FAVOR OF THE COMPANY AND/OR ITS ASSIGNEE(S) AS
PROVIDED IN THE BYLAWS OF THE COMPANY."

            (d) Any legend required by appropriate blue sky officials.

      11. INVESTMENT REPRESENTATIONS. In connection with the purchase of the
Stock, Purchaser represents to the Company the following:

            (a) Purchaser is aware of the Company's business affairs and
financial condition and has acquired sufficient information about the Company to
reach an informed and knowledgeable decision to acquire the Stock. Purchaser is
purchasing the Stock for investment for Purchaser's own account only and not
with a view to, or for resale in connection with, any "distribution" thereof
within the meaning of the Act.

            (b) Purchaser understands that the Stock has not been registered
under the Act by reason of a specific exemption therefrom, which exemption
depends upon, among other things, the bona fide nature of Purchaser's investment
intent as expressed herein.

            (c) Purchaser further acknowledges and understands that the Stock
must be held indefinitely unless the Stock is subsequently registered under the
Act or an exemption from such registration is available. Purchaser further
acknowledges and understands that the Company is under no obligation to register
the Stock. Purchaser understands that the certificate evidencing the Stock will
be imprinted with a legend which prohibits the transfer of the Stock unless the
Stock is registered or such registration is not required in the opinion of
counsel for the Company.

                                        4
<PAGE>

            (d) Purchaser is familiar with the provisions of Rules 144, under
the Act, as in effect from time to time, which, in substance, permit limited
public resale of "restricted securities" acquired, directly or indirectly, from
the issuer thereof (or from an affiliate of such issuer), in a non-public
offering subject to the satisfaction of certain conditions.

      The Stock may be resold by Purchaser in certain limited circumstances
subject to the provisions of Rule 144, which requires, among other things: (i)
the availability of certain public information about the Company and (ii) the
resale occurring following the required holding period under Rule 144 after the
Purchaser has purchased, and made full payment of (within the meaning of Rule
144), the securities to be sold.

            (e) Purchaser further understands that at the time Purchaser wishes
to sell the Stock there may be no public market upon which to make such a sale,
and that, even if such a public market then exists, the Company may not be
satisfying the current public information requirements of Rule 144, and that, in
such event, Purchaser would be precluded from selling the Stock under Rule 144
even if the minimum holding period requirement had been satisfied.

            (f) Purchaser further warrants and represents that Purchaser has
either (i) preexisting personal or business relationships, with the Company or
any of its officers, directors or controlling persons, or (ii) the capacity to
protect his own interests in connection with the purchase of the Stock by virtue
of the business or financial expertise of himself or of professional advisors to
Purchaser who are unaffiliated with and who are not compensated by the Company
or any of its affiliates, directly or indirectly.

      12. MARKET STAND-OFF AGREEMENT. Purchaser shall not sell, dispose of,
transfer, make any short sale of, grant any option for the purchase of, or enter
into any hedging or similar transaction with the same economic effect as a sale,
any Common Stock or other securities of the Company held by Purchaser, including
the Stock (the "Restricted Securities"), for a period of time specified by the
managing underwriter (not to exceed one hundred eighty (180) days) following the
effective date of a registration statement of the Company filed under the Act.
Purchaser agrees to execute and deliver such other agreements as may be
reasonably requested by the Company and/or the managing underwriter which are
consistent with the foregoing or which are necessary to give further effect
thereto, provided that all similarly situated officers are similarly bound. In
order to enforce the foregoing covenant, the Company may impose stop transfer
instructions with respect to Purchaser's Restricted Securities until the end of
such period. The underwriters of the Company's stock are intended third party
beneficiaries of this Section 12 and shall have the right, power and authority
to enforce the provisions hereof as though they were a party hereto.

      13. SECTION 83(b) ELECTION. Purchaser understands that Section 83(a) of
the Internal Revenue Code of 1986, as amended (the "Code"), taxes as ordinary
income the difference between the amount paid for the Stock and the fair market
value of the Stock as of the date any restrictions on the Stock lapse. In this
context, "restriction" includes the right of the Company to buy back the Stock
pursuant to the Repurchase Option set forth in Section 2(a) above. Purchaser
understands that Purchaser may elect to be taxed at the time the Stock is

                                        5
<PAGE>

purchased, rather than when and as the Repurchase Option expires, by filing an
election under Section 83(b) (an "83(b) Election") of the Code with the Internal
Revenue Service within thirty (30) days from the date of purchase. Even if the
fair market value of the Stock at the time of the execution of this Agreement
equals the amount paid for the Stock, the 83(b) Election must be made to avoid
income under Section 83(a) in the future. Purchaser understands that failure to
file such an 83(b) Election in a timely manner may result in adverse tax
consequences for Purchaser. Purchaser further understands that an additional
copy of such 83(b) Election is required to be filed with his or her federal
income tax return for the calendar year in which the date of this Agreement
falls. Purchaser acknowledges that the foregoing is only a summary of the effect
of United States federal income taxation with respect to purchase of the Stock
hereunder, and does not purport to be complete. Purchaser further acknowledges
that the Company has directed Purchaser to seek independent advice regarding the
applicable provisions of the Code, the income tax laws of any municipality,
state or foreign country in which Purchaser may reside, and the tax consequences
of Purchaser's death. Purchaser assumes all responsibility for filing an 83(b)
Election and paying all taxes resulting from such election or the lapse of the
restrictions on the Stock.

      14. REFUSAL TO TRANSFER. The Company shall not be required (a) to transfer
on its books any shares of Stock of the Company which shall have been
transferred in violation of any of the provisions set forth in this Agreement or
(b) to treat as owner of such shares or to accord the right to vote as such
owner or to pay dividends to any transferee to whom such shares shall have been
so transferred.

      15. NO EMPLOYMENT RIGHTS. This Agreement is not an employment contract and
nothing in this Agreement shall affect in any manner whatsoever the right or
power of the Company (or a parent or subsidiary of the Company) to terminate
Purchaser's employment for any reason at any' time, with or without cause and
with or without notice.

      16. MISCELLANEOUS.

            (a) NOTICES. Any notice required or permitted hereunder shall be
given in writing and shall be deemed effectively given upon personal delivery or
sent by telegram or fax or upon deposit in the United States Post Office, by
registered or certified mail with postage and fees prepaid, addressed to the
other party hereto at his address hereinafter shown below its signature or at
such other address as such party may designate by advance written notice to the
other party hereto.

            (b) SUCCESSORS AND ASSIGNS. This Agreement shall inure to the
benefit of the successors and assigns of the Company and, subject to the
restrictions on transfer herein set forth, be binding upon Purchaser,
Purchaser's successors, and assigns. The Repurchase Option of the Company
hereunder shall be assignable by the Company at any time or from time to time,
in whole or in part.

            (c) ATTORNEYS' FEES; SPECIFIC PERFORMANCE. Purchaser shall reimburse
the Company for all costs incurred by the Company in enforcing the performance
of, or protecting its rights under, any part of this Agreement, including
reasonable costs of investigation and attorneys' fees. It is the intention of
the parties that the Company, upon

                                        6
<PAGE>

exercise of the Repurchase Option and payment of the Option Price, pursuant to
the terms of this Agreement, shall be entitled to receive the Stock, in specie,
in order to have such Stock available for future issuance without dilution of
the holdings of other shareholders. Furthermore, it is expressly agreed between
the parties that money damages are inadequate to compensate the Company for the
Stock and that the Company shall, upon proper exercise of the Repurchase Option,
be entitled to specific enforcement of its rights to purchase and receive said
Stock.

            (d) GOVERNING LAW; VENUE. This Agreement shall be governed by and
construed in accordance with the laws of the State of Delaware. The parties
agree that any action brought by either party to interpret or enforce any
provision of this Agreement shall be brought in, and each party agrees to, and
does hereby, submit to the jurisdiction and venue of, the appropriate state or
federal court for the district encompassing the Company's principal place of
business.

            (e) FURTHER EXECUTION. The parties agree to take all such further
action (s) as may reasonably be necessary to carry out and consummate this
Agreement as soon as practicable, and to take whatever steps may be necessary to
obtain any governmental approval in connection with or otherwise qualify the
issuance of the securities that are the subject of this Agreement.

            (f) INDEPENDENT COUNSEL. Purchaser acknowledges that this Agreement
has been prepared on behalf of the Company by Heller Ehrman White & McAuliffe
LLP, counsel to the Company and that Heller Ehrman White & McAuliffe LLP does
not represent, and is not acting on behalf of, Purchaser. Purchaser has been
provided with an opportunity to consult with Purchaser's own counsel with
respect to this Agreement.

            (g) ENTIRE AGREEMENT; AMENDMENT. This Agreement constitutes the
entire agreement between the parties with respect to the subject matter hereof
and supersedes and merges all prior agreements or understandings, whether
written or oral. This Agreement may not be amended, modified or revoked, in
whole or in part, except by an agreement in writing signed by each of the
parties hereto.

            (h) SEVERABILITY. If one or more provisions of this Agreement are
held to be unenforceable under applicable law, the parties agree to renegotiate
such provision in good faith. In the event that the parties cannot reach a
mutually agreeable and enforceable replacement for such provision, then (i) such
provision shall be excluded from this Agreement, (ii) the balance of the
Agreement shall be interpreted as if such provision were so excluded and (iii)
the balance of the Agreement shall be enforceable in accordance with its terms.

            (i) COUNTERPARTS. This Agreement may be executed in two or more
counterparts, each of which shall be deemed an original and all of which
together shall constitute one instrument.

                                        7
<PAGE>

      IN WITNESS WHEREOF, the parties hereto have executed this Agreement as of
the day and year first above written.

                                    ALGORX PHARMACEUTICALS, INC.

                                    By:________________________________________

                                    Title:_____________________________________

                                    Address: 101 Interchange Plaza
                                             Suite 102
                                             Cranberry, New Jersey 08512

PURCHASER ACKNOWLEDGES AND AGREES THAT THE VESTING OF SHARES PURSUANT TO SECTION
2 HEREOF IS EARNED ONLY BY CONTINUING SERVICE AS AN EMPLOYEE OR CONSULTANT AT
THE WILL OF THE COMPANY. PURCHASER FURTHER ACKNOWLEDGES AND AGREES THAT NOTHING
IN THIS AGREEMENT SHALL CONFER UPON PURCHASER ANY RIGHT WITH RESPECT TO
CONTINUATION OF SUCH EMPLOYMENT OR CONSULTING RELATIONSHIP WITH THE COMPANY, NOR
SHALL IT INTERFERE IN ANY WAY WITH PURCHASER'S RIGHT OR THE COMPANY'S RIGHT TO
TERMINATE PURCHASER'S EMPLOYMENT OR CONSULTING RELATIONSHIP AT ANY TIME, WITH OR
WITHOUT CAUSE.

                                    PURCHASER:

                                    ___________________________________________
                                    ___________________________________________

                                    Address: __________________________________
                                    ___________________________________________
                                    ___________________________________________

                                    NUMBER OF SHARES OF STOCK
                                    SUBJECT TO THE EARLY EXERCISE
                                    ___________________________________________

<PAGE>

                                    EXHIBIT A

                   STOCK ASSIGNMENT SEPARATE FROM CERTIFICATE

      FOR VALUE RECEIVED, ____________________________________ hereby sells,
assigns and transfers unto ALGORX PHARMACEUTICALS, INC., a Delaware corporation
(the "Company"), pursuant to the Repurchase Option under that certain Early
Exercise Stock Purchase Agreement, dated ______________ ____ , 200_, by and
between the undersigned and the Company (the "Agreement") ____________________
shares of Common Stock of the Company standing in the undersigned's name on the
books of the Company represented by Certificate No.______________________ and
does hereby irrevocably constitute and appoint the Company's Secretary attorney
to transfer said stock on the books of the Company with full power of
substitution in the premises. This Assignment may be used only in accordance
with and subject to the terms and conditions of the Agreement, in connection
with the repurchase of shares of Common Stock issued to the undersigned pursuant
to the Agreement, and only to the extent that such shares remain subject to the
Company's Repurchase Option under the Agreement.

Dated: _____________________

                                    ___________________________________________
                                    (Signature)

                                    ___________________________________________
                                    (Print Name)

[INSTRUCTION: Please do not fill in any blanks other than the signature line.
The purpose of this Assignment is to enable the Company to exercise its
repurchase option set forth in the Agreement without requiring additional
signatures on the part of Purchaser.]

<PAGE>

                                   EXHIBIT B

                           JOINT ESCROW INSTRUCTIONS

Escrow Agent
Stephen M. Davis, Esq.
Corporate Secretary
c/o Heller Ehrman White & McAuliffe LLP
120 West 45th Street
New York, NY 10036-4041

Ladies and Gentlemen:

      As Escrow Agent for both ALGORX PHARMACEUTICALS, INC., a Delaware
corporation ("Corporation") and ________________________________ ("Purchaser"),
you are hereby authorized and directed to hold the documents delivered to you
pursuant to the terms of that certain Early Exercise Stock Purchase Agreement
("Agreement") to which a copy of these Joint Escrow Instructions is attached as
Exhibit B, in accordance with the following instructions:

      1. In the event Corporation or an assignee shall elect to exercise the
Repurchase Option set forth in the Agreement, the Corporation or its assignee
will give to Purchaser and you a written notice specifying the number of shares
of stock to be purchased, the purchase price, and the time for a closing
thereunder at the principal office of the Corporation. Purchaser and the
Corporation hereby irrevocably authorize and direct you to close the transaction
contemplated by such notice in accordance with the terms of said notice.

      2. At the closing, you are directed (a) to date the stock assignments
necessary for the transfer in question, (b) to fill in the number of shares
being transferred, and (c) to deliver the same, together with the certificate
evidencing the shares of stock to be transferred, to the Corporation against the
simultaneous delivery to you of the purchase price (which may include suitable
acknowledgment of cancellation of indebtedness) for the number of shares of
stock being purchased pursuant to the exercise of the Repurchase Option.

      3. Purchaser irrevocably authorizes the Corporation to deposit with you
any certificates evidencing shares of stock to be held by you hereunder and any
additions and substitutions to said shares as specified in the Agreement.
Purchaser does hereby irrevocably constitute and appoint you as his
attorney-in-fact and agent for the term of this escrow to execute with respect
to such securities all documents necessary or appropriate to make such
securities negotiable and complete any transaction herein contemplated,
including but not limited to any appropriate filing with state or government
officials or bank officials. Subject to the provisions of this paragraph 3,
Purchaser shall exercise all rights and privileges of a shareholder of the
Corporation while the stock is held by you.

      4. This escrow shall terminate upon the exercise in full or expiration of
the Repurchase Option, whichever occurs first.

                                        1
<PAGE>

      5. If at the time of termination of this escrow you should have in your
possession any documents, securities, or other property belonging to Purchaser,
you shall deliver all of the same to Purchaser and shall be discharged of all
further obligations hereunder; provided, however, that if at the time of
termination of this escrow you are advised by the Corporation that any property
subject to this escrow is the subject of a pledge or other security agreement,
you shall deliver all such property to the pledgeholder or other person
designated by the Corporation.

      6. Except as otherwise provided in these Joint Escrow Instructions, your
duties hereunder may be altered, amended, modified or revoked only by a writing
signed by all of the parties hereto.

      7. You shall be obligated only for the performance of such duties as are
specifically set forth herein and may rely and shall be protected in relying or
refraining from acting on any instrument reasonably believed by you to be
genuine and to have been signed or presented by the proper party or parties. You
shall not be personally liable for any act you may do or omit to do hereunder as
Escrow Agent or as attorney-in-fact for Purchaser while acting in good faith and
in the exercise of your own good judgment, and any act done or omitted by you
pursuant to the advice of your own attorneys shall be conclusive evidence of
such good faith.

      8. You are hereby expressly authorized to disregard any and all warnings
given by any of the parties hereto or by any other person or corporation,
excepting only orders or process of courts of law, and are hereby expressly
authorized to comply with and obey orders, judgments or decrees of any court. In
case you obey or comply with any such order, judgment or decree of any court,
you shall not be liable to any of the parties hereto or to any other person,
firm or corporation by reason of such compliance, notwithstanding any such
order, judgment or decree being subsequently reversed, modified, annulled, set
aside, vacated or found to have been entered without jurisdiction.

      9. You shall not be liable in any respect on account of the identity,
authorities or rights of the parties executing or delivering or purporting to
execute or deliver the Agreement or any documents or papers deposited or called
for hereunder.

      10. You shall not be liable for the outlawing of any rights under any
statute of limitations with respect to these Joint Escrow Instructions or any
documents deposited with you.

      11. Your responsibilities as Escrow Agent hereunder shall terminate if you
shall cease to be Secretary of the Corporation or if you shall resign by written
notice to each party. In the event of any such termination, the Secretary of the
Corporation shall automatically become the successor Escrow Agent unless the
Corporation shall appoint another officer or assistant officer of the
Corporation as successor Escrow Agent, and Purchaser hereby confirms the
appointment of such successor as his attorney-in-fact and agent to the full
extent of your appointment.

      12. If you reasonably require other or further instruments in connection
with these Joint Escrow Instructions or obligations in respect hereto, the
necessary parties hereto shall join in furnishing such instruments.

                                        2
<PAGE>

      13. It is understood and agreed that should any dispute arise with respect
to the delivery and/or ownership or right of possession of the securities held
by you hereunder, you are authorized and directed to retain in your possession
without liability to anyone all or any part of said securities until such
dispute shall have been settled either by mutual written agreement of the
parties concerned or by a final order, decree or judgment of a court of
competent jurisdiction after the time for appeal has expired and no appeal has
been perfected, but you shall be under no duty whatsoever to institute or defend
any such proceedings.

      14. Any notice required or permitted hereunder shall be given in writing
and shall be deemed effectively given upon personal delivery, including delivery
by express courier, or five (5) days after deposit in the United States Post
Office, by registered or certified mail with postage and fees prepaid, addressed
to each of the other parties entitled to such notice at the following addresses,
or at such other addresses as a party may designate by ten days' advance written
notice to each of the other parties hereto.

      CORPORATION                   AlgoRx Pharmaceuticals, Inc.
                                    101 Interchange Plaza
                                    Suite 102
                                    Cranberry, NJ 08512

      PURCHASER:                    ____________________________
                                    ____________________________
                                    ____________________________

      ESCROW AGENT:                 Stephen M. Davis, Esq.
                                    Corporate Secretary
                                    c/o Heller Ehrman White & McAuliffe LLP
                                    120 West 45th Street
                                    New York, NY 10036-4041

      15. By signing these Joint Escrow Instructions, you become a party hereto
only for the purpose of said Joint Escrow Instructions; you do not become a
party to the Agreement.

      16. You shall be entitled to employ such legal counsel and other experts
(including, without limitation, the firm of Heller Ehrman White & McAuliffe LLP)
as you may deem necessary properly to advise you in connection with your
obligations hereunder. You may rely upon the advice of such counsel, and you may
pay such counsel reasonable compensation therefor. The Corporation shall be
responsible for all fees generated by such legal counsel in connection with your
obligations hereunder.

      17. This instrument shall be binding upon and inure to the benefit of the
parties hereto and their respective successors and permitted assigns. It is
understood and agreed that references to "you" and "your" herein refer to the
original Escrow Agents. It is understood and agreed that the Corporation may at
any time or from time to time assign its rights under the Agreement and these
Joint Escrow Instructions.

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<PAGE>

      18. This Agreement shall be governed by and interpreted and determined in
accordance with the laws of the State of Delaware, as such laws are applied by
State courts to contracts made and to be performed entirely in Delaware by
residents of that state.

                                    Very truly yours,

                                    ALGORX PHARMACEUTICALS, INC.

                                    By ________________________________________
                                       Name
                                       Title:

                                    PURCHASER

                                    By ________________________________________
                                       Name
                                       Title:

ESCROW AGENT:

Stephen M. Davis, Esq.
Heller Ehrman White & McAuliffe LLP

                                        4
<PAGE>

                                                      [For California Residents]

                                SPOUSAL CONSENT

      I am married to __________________________________ the Purchaser pursuant
to the attached Early Exercise Stock Purchase Agreement. I acknowledge that I
have read the foregoing Early Exercise Stock Purchase Agreement and that I know
its contents. I am aware that by its provisions my spouse agrees to sell all his
Shares of the Company, including my community property interest in them, if any,
on the occurrence of certain events and that I must agree to sell Shares
transferred to me in certain circumstances. I hereby consent to such sale,
approve of the provisions of the Agreement, and agree that those Shares and my
interest in them are subject to the provisions of the Agreement and that I will
take no action at any time to hinder operation of the Agreement on those Shares
or my interest in them.

Dated: _______________________

                                    ___________________________________________
                                    (SIGNATURE OF SPOUSE)

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