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                                                                  EXHIBIT 10.16


                               Neuromedica, Inc.

                             1997 Stock Option Plan
                    (reflects corrections approved in 2/98)


     1. DEFINITIONS. As used in this 1997 Stock Option Plan of Neuromedica,
Inc., the following terms shall have the following meanings:

          1.1. BOARD means the Company's Board of Directors.

          1.2. CODE means the federal Internal Revenue Code of 1986, as amended.

          1.3. COMMITTEE means a committee appointed by the Board or, if no such
     committee is appointed, the Board itself. Such committee or the Board, as
     the case may be, shall be responsible for the administration of the Plan,
     as provided in section 5 of the Plan.

          1.4. COMPANY means Neuromedica, Inc., a Delaware corporation.

          1.5. FAIR MARKET VALUE means (i) on any date prior to the Initial
     Public Offering Date, the value of a share of Stock on any such date as
     determined by the Committee, and (ii) on the Initial Public Offering Date
     or on any date thereafter, (A) the average of the closing bid and asked
     prices of a share of Common Stock on the over-the-counter market, as
     reported by the National Association of Securities Dealers, Inc. ("NASD")
     on such date, or (B) the closing price of a share of Common Stock on an
     exchange or the NASD's National Market System, as the case may be, on such
     date.

          1.6. GRANT DATE means the date as of which an Option is granted, as
     determined under Section 7.

          1.7. INCENTIVE OPTION means an Option which by its terms is to be
     treated as an "incentive stock option" within the meaning of Section 422 of
     the Code.

          1.8. INITIAL PUBLIC OFFERING DATE means the date of the closing of the
     Company's initial public offering of Common Stock.

          1.9. NON-STATUTORY OPTION means any Option that is not an Incentive
     Option.

          1.10. OPTION means an option to purchase shares of Stock granted under
     the Plan.

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          1.11. OPTION AGREEMENT means an agreement between the Company and an
     Optionee, setting forth the terms and conditions of an Option.

          1.12. OPTION PRICE means the price paid by an Optionee for a share of
     Stock upon exercise of an Option.

          1.13. OPTIONEE means a person eligible to receive an Option, as
     provided in Section 6, to whom an Option shall have been granted under the
     Plan.

          1.14. PLAN means this Stock Option Plan of the Company, as amended
     from time to time.

          1.15. STOCK means Common Stock, par value $.001 per share, of the
     Company.

          1.16. STOCK RESTRICTION AGREEMENT means an agreement, if any, between
     the Company and an Optionee setting forth INTER ALIA conditions and
     restrictions upon the transfer of shares of Stock.

          1.17. TEN PERCENT OWNER means a person who owns, or is deemed within
     the meaning of Section 422(b)(6) of the Code to own, stock possessing more
     than 10% of the total combined voting power of all classes of stock of the
     Company (or its parent or subsidiary corporations). Whether a person is a
     Ten Percent Owner shall be determined with respect to each Option based on
     the facts existing immediately prior to the Grant Date of such Option.

          1.18. VESTING YEAR for any portion of any Incentive Option means the
     calendar year in which that portion of the Option first becomes
     exercisable.

          1.19. CHANGE IN CORPORATE CONTROL means (i) the time of approval by
     the shareholders of the Company of (A) any consolidation or merger of the
     Company in which the Company is not the continuing or surviving corporation
     or pursuant to which Stock would be converted into cash, securities or
     other property, other than a merger in which the holders of Stock
     immediately prior to the merger will have the same proportionate ownership
     of common stock of the surviving corporation immediately after the merger
     as before the merger, (B) any sale, lease, exchange or other transfer (in
     one transaction or a series of related transactions) of all or
     substantially all the assets of the Company, or (C) adoption of any plan or
     proposal for the liquidation or dissolution of the Company, or (ii) the
     date on which any "person" (as defined in Section 13(d) of the Exchange
     Act), other


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     than the Company or a subsidiary or employee benefit plan or trust
     maintained by the Company or any of its subsidiaries shall become (together
     with its "affiliates" and "associates", as defined in Rule 12b-2 under the
     Exchange Act) the "beneficial owner" (as defined in Rule 13d-3 under the
     Exchange Act), directly or indirectly, of more than 25% of the Stock
     outstanding at the time, without the prior approval of the Board of
     Directors of the Company.

     2. PURPOSE. This Plan is intended to encourage ownership of Stock by
employees and consultants of the Company and its subsidiaries and to provide
additional incentives for them to promote the success of the Company's business.
The Plan is intended to be an incentive stock option plan within the meaning of
Section 422 of the Code but not all Options granted hereunder are required to be
Incentive Options.

     3. TERM OF THE PLAN. Options may be granted hereunder at any time in the
period commencing on the approval of the Plan by the Board and ending March 10,
2007.

     4. STOCK SUBJECT TO THE PLAN. Subject to the provisions of Section 17 of
the Plan, at no time shall the number of shares of Stock then outstanding which
are attributable to the exercise of Options granted under the Plan, plus the
number of shares then issuable upon exercise of outstanding Options granted
under the Plan, exceed 50,000 shares. Shares to be issued upon the exercise of
Options granted under the Plan may be either authorized but unissued shares or
shares held by the Company in its treasury. If any Option expires or terminates
for any reason without having been exercised in full, the shares not purchased
thereunder shall again be available for Options thereafter to be granted.

     5. ADMINISTRATION. The Plan shall be administered by the Committee. Subject
to the provisions of the Plan, the Committee shall have complete authority, in
its discretion, to make or to select the manner of making the following
determinations with respect to each Option to be granted by the Company: (a) the
employee or consultant to receive the Option; (b) whether the Option (if granted
to an employee) will be an Incentive Option or Non-statutory Option; (c) the
time of granting the Option; (d) the number of shares subject to the Option; (e)
the Option Price; (f) the Option period; (g) the Option exercise date or dates;
and (h) the effect of termination of employment, consulting or association with
the Company on the subsequent exercisability of the Option. In making such
determinations, the Committee may take into account the nature of the services
rendered by the respective employees and consultants, their present and
potential contributions to the success of the Company and its subsidiaries, and
such other factors as the Committee in its discretion shall deem relevant.
Subject to the provisions of the Plan, the Committee shall also have complete
authority to interpret the Plan, to prescribe, amend and rescind



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rules and regulations relating to it, to determine the terms and provisions
of the respective Option Agreements (which need not be identical), and to make
all other determinations necessary or advisable for the administration of the
Plan. The Committee's determinations on the matters referred to in this Section
5 shall be conclusive.

     6. ELIGIBILITY. An Option shall be granted only to an employee or
consultant of one or more of the Company or any subsidiary thereof. A director
of one or more of the Company and any subsidiary who is not also an employee or
consultant of one or more of the Company or a subsidiary shall not be eligible
to receive an Option.

     7. TIME OF GRANTING OPTIONS. The granting of an Option shall take place at
the time specified in the Option Agreement. Only if expressly so provided in the
Option Agreement, shall the Grant Date be the date on which an Option Agreement
shall have been duly executed and delivered by the Company and the Optionee.

     8. OPTION PRICE. The Option Price under each Incentive Option shall be not
less than 100% of the Fair Market Value of Stock on the Grant Date, or not less
than 110% of the Fair Market Value of Stock on the Grant Date if the Optionee is
a Ten Percent Owner. The Option Price under each Non-statutory Option shall not
be so limited solely by reason of this Section 8.

     9. OPTION PERIOD. No Incentive Option may be exercised later than the tenth
anniversary of the Grant Date, but in any case not later than the fifth
anniversary of the Grant Date, if the Optionee is a Ten Percent Owner. The
Option period under each Non-statutory Option shall not be so limited solely by
reason of this Section 9. An Option may become exercisable in such installments,
cumulative or non-cumulative, as the Committee may determine. In the case of an
Option not otherwise immediately exercisable in full, the Committee may
accelerate the exercisability of such Option in whole or in part at any time,
provided the acceleration of the exercisability of any Incentive Option would
not cause the Option to fail to comply with the provisions of Section 422 of the
Code.

     10. LIMIT ON INCENTIVE OPTION CHARACTERIZATION. No Incentive Option shall
be considered an Incentive Option to the extent that pursuant to its terms it
would permit the Optionee to purchase for the first time in any Vesting Year
under that Incentive Option more than the number of shares of Stock calculated
by dividing the current limit by the Option Price. The current limit for any
Optionee for any Vesting Year shall be $100,000 minus the aggregate Fair Market
Value at the date of grant of the number of shares of Stock available for
purchase for the first time in the Vesting Year under each other Incentive
Option granted to the Optionee under the Plan after December 31, 1986 and each
other incentive stock option granted to the Optionee after December



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31, 1986 under any other incentive stock option plan of the Company (and
any parent and subsidiary corporations).

     11. EXERCISE OF OPTION. An Option may be exercised by the Optionee giving
written notice, in the manner provided in Section 22, specifying the number of
shares with respect to which the Option is then being exercised. Such notice
shall be accompanied by payment in the form of cash, or certified or bank check
payable to the order of the Company, in an amount equal to the option price of
the shares to be purchased. In the event that notice of exercise is given prior
to the Initial Public Offering Date, such notice shall be accompanied by an
executed counterpart of a Stock Restriction Agreement, if any, if the exercising
Optionee is not already a party to a Stock Restriction Agreement. Payment may at
the election of the Optionee be made in whole or in part by the surrender of a
whole number of shares of previously issued Stock of the Company. Previously
issued shares of Stock shall be accepted in an amount equal to the then Fair
Market Value of the surrendered shares. In addition, the Optionee may surrender
a portion of his Option with respect to vested Shares as payment for other
Shares which have also vested, and in such case the portion of the Option
surrendered shall be considered a payment equal to the Fair Market Value of the
vested Option Shares which could be purchased with the surrendered portion of
the Option less the aggregate exercise price for such Option Shares. The Company
may, in the sole discretion of the Committee, make an advance to the Optionee of
his salary in an amount sufficient to cover any applicable withholding taxes
resulting from Option exercise. Receipt by the Company of notice, payment and,
if applicable, executed counterpart shall constitute the exercise of the Option.
Within 30 days thereafter but subject to the remaining provisions of the Plan,
the Company shall deliver or cause to be delivered to the Optionee or his agent
a certificate or certificates for the number of shares then being purchased.
Such shares shall be fully paid and nonassessable.

     12. RESTRICTIONS ON ISSUE OF SHARES.

     (a) Notwithstanding any other provision of the Plan, if, at any time, in
the reasonable opinion of the Company the issuance of shares of Stock covered by
the exercise of any Option may constitute a violation of law, then the Company
may delay such issuance and the delivery of a certificate for such shares until
(i) approval shall have been obtained from such governmental agencies, other
than the Securities and Exchange Commission, as may be required under any
applicable law, rule, or regulation; and (ii) in the case where such issuance
would constitute a violation of a law administered by or a regulation of the
Securities and Exchange Commission, one of the following conditions shall have
been satisfied:



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          (1) the shares with respect to which such Option has been exercised
     are at the time of the issue of such shares effectively registered under
     the Securities Act of 1933, as amended (the "Securities Act"); or

          (2) a no-action letter in form and substance reasonably satisfactory
     to the Company and its counsel with respect to the issuance of such shares
     shall have been obtained by the Company from the Securities and Exchange
     Commission.

The Company shall make all reasonable efforts to bring about the occurrence of
said events.

     (b) Each certificate representing shares issued upon the exercise of an
Option will bear restrictive legends which may refer to this Plan and to
applicable restrictions under a Stock Restriction Agreement.

     13. PURCHASE FOR INVESTMENT; SUBSEQUENT REGISTRATION.

     (a) Unless the shares to be issued upon exercise of an Option granted under
the Plan have been effectively registered under the Securities Act, the Company
shall be under no obligation to issue any shares covered by any Option unless
the person who exercises such Option, in whole or in part, shall give a written
representation to the Company which is satisfactory in form and substance to its
counsel and upon which the Company may reasonably rely, that he or she is
acquiring the shares issued pursuant to such exercise of the Option as an
investment and not with a view to, or for sale in connection with, the
distribution of any such shares.

     (b) Each share of Stock issued pursuant to the exercise of an Option
granted pursuant to this Plan may bear a reference to the investment
representation made in accordance with this Section 13 and to the fact that no
registration statement has been filed with the Securities and Exchange
Commission in respect to said Stock.

     (c) If the Company shall deem it necessary or desirable to register under
the Securities Act or other applicable statutes any shares with respect to which
an Option shall have been granted, or to qualify any such shares for exemption
from the Securities Act or other applicable statutes, then the Company shall
take such action at its own expense. The Company may require from each Option
holder, or each holder of shares of Stock acquired pursuant to the Plan, such
information in writing for use in any registration statement, prospectus,
preliminary prospectus or offering circular as is reasonably necessary for such
purpose and may require reasonable indemnity to the Company and its officers and
directors from such holder against all losses, claims, damage and liabilities
arising from such use of the information so furnished and



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caused by any untrue statement of any material fact therein or caused by
the omission to state a material fact required to be stated therein or necessary
to make the statements therein not misleading in the light of the circumstances
under which they were made.

     14. WITHHOLDING; NOTICE OF DISPOSITION OF STOCK PRIOR TO EXPIRATION OF
SPECIFIED HOLDING PERIOD.

     (a) Whenever shares are to be issued in satisfaction of an Option granted
hereunder, the Company shall have the right to require the Optionee to remit to
the Company an amount sufficient to satisfy federal, state, local or other
withholding tax requirements if and to the extent required by law (whether so
required to secure for the Company an otherwise available tax deduction or
otherwise) prior to the delivery of any certificate or certificates for such
shares.

     (b) The Company may require as a condition to the issuance of shares
covered by any Incentive Option that the party exercising such Option give a
written representation to the Company which is satisfactory in form and
substance to its counsel and upon which the Company may reasonably rely, that he
or she will report to the Company any disposition of such shares prior to the
expiration of the holding periods specified by Section 422(a)(1) of the Code. If
and to the extent that the realization of income in such a disposition imposes
upon the Company federal, state, local or other withholding tax requirements, or
any such withholding is required to secure for the Company an otherwise
available tax deduction, the Company shall have the right to require that the
recipient remit to the Company an amount sufficient to satisfy those
requirements; and the Company may require as a condition to the issuance of
shares covered by an Incentive Option that the party exercising such option give
a satisfactory written representation promising to make such a remittance.

     15. TERMINATION OF ASSOCIATION WITH THE COMPANY. If the Optionee's
employment or association with the Company is terminated, whether voluntarily or
otherwise, the Option, to the extent the Option is exercisable on the date of
termination, may be exercised by the Optionee, but only within 90 days after he
or she ceases to be an employee of or consultant to the Company, unless
terminated earlier by its terms. Notwithstanding the foregoing, in the event
that the applicable Option Agreement with respect to an Option shall contain
specific provisions governing the effect that any such termination shall have on
the exercisability of such Option, such provisions in the Option Agreement
shall, to the extent that they are inconsistent with the provisions of this
Section 15, control and deem to supersede the provisions of this Section 15. For
purposes of this Section 15, military or sick leave shall not be deemed a
termination of employment, PROVIDED that it does not exceed the longer of 120
days or the period during which the absent Optionee's reemployment rights, if
any, are guaranteed by statute or by contract.



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     16. TRANSFERABILITY OF OPTIONS. Options shall not be transferable,
otherwise than by will or the laws of descent and distribution, and may be
exercised during the life of the Optionee only by the Optionee.

     17. ADJUSTMENT OF NUMBER AND KIND OF OPTION SHARES.

     (a) In the event of any stock dividend payable in Stock or any split-up or
contraction in the number of shares of Stock after the date of an Option
Agreement and prior to the exercise in full of the Option, the number of shares
subject to such Option Agreement and the price to be paid for each share subject
to the Option shall be proportionately adjusted. In the event of any
reclassification, exchange, conversion or change of outstanding shares of Stock,
or in case of any consolidation or merger of the Company with or into another
company, or in case of any sale or conveyance to another company or entity of
the property of the Company as a whole or substantially as a whole, shares of
stock or other securities equivalent in kind and value to those shares an
Optionee would have received if he or she had held the full number of shares of
Stock subject to the Option immediately prior to such reclassification,
exchange, conversion, change, consolidation, merger, sale or conveyance and had
continued to hold those shares (together with all other shares, stock and
securities thereafter issued in respect thereof) to the time of the exercise of
the Option shall thereupon be subject to the Option. Upon dissolution or
liquidation of the Company, the Option shall terminate, but the Optionee (if at
the time in the employ of or retained as a consultant to the Company or any of
its subsidiaries) shall have the right, immediately prior to such dissolution or
liquidation, to exercise the Option to the extent exercisable on the date of
such dissolution or liquidation. No fraction of a share shall be purchasable or
deliverable upon exercise, but in the event any adjustment hereunder of the
number of shares covered by the Option shall cause such number to include a
fraction of a share, such number of shares shall be adjusted to the nearest
smaller whole number of shares. In the event of changes in the outstanding Stock
by reason of any stock dividend, split-up, contraction, reclassification, or
change of outstanding shares of Stock of the nature contemplated by this Section
17, the number of shares of Stock available for the purpose of the Plan as
stated in Section 4 shall be correspondingly adjusted.

     (b) Upon the close of business on the Initial Public Offering Date, each
Option then outstanding shall cease to be exercisable for shares of Stock and
shall become exercisable for shares of Common Stock of the Company. The number
of shares of Common Stock that shall become subject to each such Option upon the
close of business on the Initial Public Offering Date shall be equal to the
number of shares of Stock subject to each such Option on the date immediately
preceding such Initial Public Offering Date. From and after the Initial Public
Offering Date, each such Option shall be exercisable only in accordance with the
terms set forth in, and to the extent provided in, this Plan or any applicable
Option Agreement (including, without limitation,


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any vesting schedule set forth therein), all to the same extent as if each such
Option were still exercisable for shares of Stock. Without limiting the
generality of the preceding sentence, nothing in this Section 17(b) shall be
construed as accelerating the exercisability of any Option.

     18. CHANGE IN CORPORATE CONTROL. Upon a change in Corporate Control, each
outstanding Option shall immediately become fully exercisable.

     19. RESERVATION OF STOCK. The Company shall at all times during the term of
the Options reserve or otherwise keep available such number of shares of Stock
as will be sufficient to satisfy the requirements of the Plan and shall pay all
fees and expenses necessarily incurred by the Company in connection therewith.

     20. LIMITATION OF RIGHTS IN STOCK; NO SPECIAL EMPLOYMENT OR OTHER RIGHTS.
The Optionee shall not be deemed for any purpose to be a stockholder of the
Company with respect to any of the shares of Stock covered by an Option, except
to the extent that the Option shall have been exercised with respect thereto
and, in addition, a certificate shall have been issued therefor and delivered to
the Optionee or his agent. Any Stock issued pursuant to the Option shall be
subject to all restrictions upon the transfer thereof which may be now or
hereafter imposed by the Certificate of Incorporation, the By-laws of the
Company, and a Stock Restriction Agreement. Nothing contained in the Plan or in
any Option shall confer upon any Optionee any right with respect to the
continuation of his or her employment with, or retention as a consultant by, the
Company (or any subsidiary), or interfere in any way with the right of the
Company (or any subsidiary), subject to the terms of any separate employment or
consulting agreement or provision of law or corporate articles or by-laws to the
contrary, at any time to terminate such employment or consulting agreement or to
increase or decrease the compensation of the Optionee from the rate in existence
at the time of the grant of an Option.

     21. TERMINATION AND AMENDMENT OF THE PLAN. The Board may at any time
terminate the Plan or make such modifications of the Plan as it shall deem
advisable. No termination or amendment of the Plan may, without the consent of
the Optionee to whom any Option shall theretofore have been granted, adversely
affect the rights of such Optionee under such Option.

     22. NOTICES AND OTHER COMMUNICATIONS. All notices and other communications
required or permitted under the Plan shall be effective if in writing and if
delivered or sent by certified or registered mail, return receipt requested (a)
if to the Optionee, at his or her residence address last filed with the Company,
and (b) if to the Company, at 1100 E. Hector Street, Suite 450, Conshohocken, PA
19428, with a copy to its Chief Financial Officer at such address, or to



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such other persons or addresses as the Optionee or the Company may specify by
a written notice to the other from time to time.












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