<PAGE>
                                                                 EXHIBIT 4(a)(b)

                                 PHARMOS CORPORATION
                            STOCK PURCHASE AGREEMENT

          THIS STOCK PURCHASE AGREEMENT (this "Agreement") is made as of
December 12, 1996 by and between Pharmos Corporation (the "Company"), a Nevada
corporation having its principal offices at 2 Innovation Drive, Alachua, FL
32615, and Bausch & Lomb Pharmaceuticals, Inc., a Delaware corporation having
its principal offices at 8500 Hidden River Parkway, Tampa, FL 33637 ("BLP").

                                   BACKGROUND
                                   ----------

          A.  The Company has provided to BLP information regarding the Company
and the Company's Common Stock, par value $.03 per share ("Common Stock").

          B.  The Company has developed and is currently seeking approval of
certain drug products for the treatment of ophthalmic disorders.  BLP, in the
course of its association with the Company, has investigated such products as
well as other drug substances and products which may be offered by the Company,
and believes that the purchase of the Common Stock represents a sound investment
in the Company and its future growth apart from other business activities and
ventures between the Company and BLP.

          C.  Based upon BLP's review of the information provided by the
Company, BLP's discussions with representatives of the Company, BLP's
independent investigation of the Company and its reliance on the warranties and
representations made by the Company herein, BLP desires to purchase, and the
Company desires to sell, shares of Common Stock upon the terms and conditions
set forth herein.

          NOW THEREFORE, in consideration of the premises and for other good and
lawful considerations, the receipt and sufficiency of which is hereby
acknowledged, the parties, intending to be legally bound, do hereby agree:

                                   AGREEMENT
                                   ---------

          1.    Sale of Stock.
                -------------

          1.1   Authorization.  The Company has duly authorized the issuance and
                -------------
sale of the shares of Common Stock (the "Shares") which are being issued and
sold in accordance with the terms of this Agreement.

          1.2  Sale.  Subject to the terms and conditions of this Agreement, at
               ----
the Closing (as hereinafter defined) the Company shall sell and issue to BLP,
and BLP shall purchase, the Shares at a price per share equal to the lower of
(i) the average of the closing prices for a share of Common Stock as reported in
the East Coast edition of the Wall Street Journal for the fifteen (15) trading
days ending immediately prior to the date of this Agreement, and (ii) the
closing price for a share of Common Stock as reported in the East Coast edition
of the Wall Street Journal for the trading day immediately prior to the date of
this Agreement, in either case for
<PAGE>

an aggregate purchase price of $2,000,000.

          1.3  Closing.  The purchase and sale of the shares shall take place at
               -------
the offices of the Company's counsel, Eilenberg & Zivian, New York, NY, upon the
execution of this Agreement, or at such other time and place as the Company and
BLP shall mutually agree in writing (which time and place are referred to herein
as the "Closing").  At the Closing, the Company will deliver to BLP a copy of an
irrevocable letter of instructions to the registrar and transfer agent of the
Company's Common Stock directing the issuance of a certificate representing the
Shares, against payment by BLP to the Company of the purchase price therefor by
wire transfer of immediately available U.S. funds or other method acceptable to
the Company, with certificates representing the Shares to be delivered to BLP
within ten (10) days after the Closing.

     1.4  Legend.  The certificates representing the Shares to be issued at
          ------
 Closing will bear the following legend:
              ----

          THE SHARES REPRESENTED BY THIS CERTIFICATE HAVE NOT BEEN REGISTERED
          UNDER THE SECURITIES ACT OF 1933, AS AMENDED, AND MAY NOT BE OFFERED,
          SOLD OR OTHERWISE TRANSFERRED, PLEDGED, OR HYPOTHECATED EXCEPT
          PURSUANT TO (i) A REGISTRATION STATEMENT WITH RESPECT TO SUCH
          SECURITIES THAT IS EFFECTIVE UNDER SUCH ACT, (ii) RULE 144 OR RULE
          144A UNDER SUCH ACT, OR (iii) ANY OTHER EXEMPTION FROM REGISTRATION
          UNDER SUCH ACT RELATING TO THE DISPOSITION OF SECURITIES.

     2.   Representations and Warranties of the Company.  The Company does
          ---------------------------------------------
hereby represent and warrant to BLP that:

     2.1  Organization and Good Standing.  The Company is a corporation duly
          ------------------------------
organized, validly existing and in good standing under the laws of the State of
Nevada.  The Company has full power and authority to own or lease and to operate
its properties and to conduct its business as presently conducted.  The Company
is duly qualified to do business as a foreign corporation and is in good
standing in each jurisdiction in which the failure to so qualify would have a
material adverse effect on the operations or financial condition of the Company.

     2.2  Authority.  The execution, delivery and performance by the Company of
          ---------
this Agreement and the consummation by the Company of the transaction
contemplated hereby have been duly authorized by all necessary corporate action.
This Agreement has been duly executed and delivered by the Company and
constitutes a valid and binding obligation of the Company, enforceable in
accordance with its terms, except as may be limited by bankruptcy, insolvency,
reorganization, moratorium or other laws affecting the rights and remedies of
creditors generally and as may be limited by general equitable principles.

     2.3  Non-Contravention.  The execution of, performance under and compliance
          -----------------
with this Agreement by the Company will not violate any provision of law and
will not conflict with or result in any breach of any of the terms, conditions,
or provisions of, or constitute, with or without the passage of time or the
giving of notice, a default under, or give to any person the right to exercise
any remedy under, or to accelerate the maturity of, or to cancel, terminate or
<PAGE>

modify, or require a consent or waiver under, its Articles of Incorporation or
By-laws (each as amended and presently in effect) or any indenture, lease,
agreement or other instrument to which the Company is a party or by which it or
any of its properties is bound.

     2.4  Capitalization.  The authorized capital stock of the Company
          --------------
(immediately prior to the Closing) is 50,000,000 shares of Common Stock, par
value $.03 per share, of which 29,219,969 shares were issued and outstanding as
of September 30, 1996, and 1,250,000 shares of undesignated preferred stock, no
par value per share, of which 1,900 Series A Convertible Preferred shares are
issued and outstanding.  All of such outstanding common shares have been validly
issued and are fully paid and non-assessable.  No class of capital stock of the
Company is entitled to preemptive rights.  Since the date of the Company's most
recent '34 Act Filing (as hereinafter defined), the Company has not changed the
amount of its authorized capital stock or purchased any shares of its capital
stock, or subdivided or otherwise changed any shares of any class of its capital
stock, whether by way of reclassification, recapitalization, stock split or
otherwise, or issued or reissued, or agreed to issue or reissue any of its
capital stock, and has not since such date declared or paid any dividend in cash
or stock or made any other distribution of assets to its shareholders.  Except
as described in the Company's '34 Act Filings (as hereinafter defined) and
pursuant to this Agreement, at the date hereof, there are no shares of capital
stock or other equity securities of the Company's outstanding and no outstanding
options, warrants, scrip, rights to subscribe to, calls or commitments of any
character whatsoever relating to, or securities or rights convertible into,
shares of any capital stock of the Company or any of its subsidiaries, or
contracts, commitments, understandings, or arrangements by which the Company or
any of its subsidiaries is or may become bound to issue additional shares of its
capital stock or options, warrants or rights to purchase or acquire any shares
of its capital stock.

     2.5  Validity of Shares.  The Shares have been duly authorized and reserved
          ------------------
for issuance and, upon their issuance in accordance with the terms hereof, will
be validly issued, fully paid and non-assessable.  The Common Stock is traded on
NASDAQ SmallCap Market.

     2.6  Compliance with Law.  The Company is not in default with respect to
          -------------------
any judgment, order, writ, injunction, decree or award, and the Company is not
in violation of, and the business of the Company is presently being conducted so
as to comply in all material respects with, applicable Federal, state and local
governmental laws and regulations, including, without limitation, laws and
regulations relating to environmental requirements (such as requirements in
respect of air, water and noise pollution) drug testing, manufacturing and
distribution, and to employment practices (such as practices in respect of
discrimination, wage and hour and health and safety), all to the extent
necessary to avoid any material adverse effect on the business, properties or
financial condition of the Company.

     2.7  Governmental Consent, etc.  The Company is not required to obtain any
          -------------------------
consent, approval or authorization of, or to make any declaration or filing
with, any governmental authority as a condition to or in connection with the
valid execution, delivery and performance of this Agreement and the valid offer,
sale or delivery of the Shares, or the performance by the Company of its
obligations in respect thereof.

     2.8  Taxes.  The Company and its subsidiaries have filed or caused to be
          -----
filed, or will file within the time period prescribed by law, all federal and
state income tax returns which are
<PAGE>

required to be filed and have paid or caused to be paid all taxes to the extent
that such taxes have become due and payable, except taxes the validity or amount
of which is being contested in good faith by appropriate proceedings and with
respect to which adequate reserves have been set aside.  The Company has paid or
caused to be paid, or has established reserves adequate in all material
respects, for all Federal income tax liabilities and state income tax
liabilities applicable to the Company for all fiscal years which have not been
examined and reported on by the taxing authorities (or closed by applicable
statutes).

     2.9  Material Adverse Change.  Except as described in the Company's filings
          -----------------------
with the SEC under the Securities and Exchange Act of 1934, as amended (the "'34
Act") during the twelve (12) months prior to the date of this Agreement (the
"'34 Act Filings") or as otherwise previously disclosed in writing to BLP and
identified as an exception to this representation, there has been no material
adverse change in the business, financial condition, or results of operations of
the Company since the date of the most recent '34 Act Filing.

     2.10 ERISA.  No accumulated funding deficiency (as defined in Section 302
          -----
of ERISA and Section 412 of the Internal Revenue Code of 1986, as amended (the
"Code")), whether or not waived, exists with respect to any Plan (as defined
below) (other than a Multiemployer Plan (as defined below)).  No liability to
the Pension Benefit Guaranty Corporation has been incurred with respect to any
Plan (other than a Multiemployer Plan) by the Company which is or would be
materially adverse to the Company taken as a whole.  Neither the Company nor any
of its subsidiaries has incurred any withdrawal liability under Title IV of
ERISA with respect to any Multiemployer Plan which is or would be materially
adverse to the Company and its subsidiaries taken as a whole.  The execution and
delivery of this Agreement and the sale of the Shares will not involve any
transaction which is subject to the prohibitions of Section 406 of ERISA or in
connection with which a tax could be imposed pursuant to Section 4975 of the
Code.  As used in this Section 2.11, the term "Plan" shall mean an "employee
pension benefit plan" (as defined in Section 392 of ERISA) which is or has been
established or maintained, or to which contributions are or have been made, by
the Company or by any trade or business, whether or not incorporated, which,
together with the Company, is under common control, as described in Section
414(b) or (c) of the Code; and the term "Multiemployer Plan" shall mean any Plan
which is a "multiemployer plan" (as such term is defined in section 4001(a)(3)
of ERISA).

     2.11 Possession of Franchises, Licenses, etc.  To the Company's knowledge,
          ---------------------------------------
the Company possesses all franchises, certificates, licenses, permits and other
authorizations from governmental political subdivisions or regulatory
authorities that are necessary in any material respect for the ownership,
maintenance and operation of their respective properties and assets, and to
conduct the businesses now conducted or proposed to be conducted, and the
Company is not in violation of any thereof in any material respect.

     2.12 Trademarks, Patents, etc.  To the Company's knowledge, the Company
          ------------------------
owns, or possesses the right to use to the extent necessary in its businesses,
all trade secrets, trademarks, trade names, copyrights, patents, patent rights,
computer software, licenses and other assets considered to be "intangible
assets" in accordance with generally accepted accounting principles
(collectively, "Intangible Assets") that are used or are necessary in any
material respect in the conduct of its business as now operated.  No such
Intangible Asset, to the best knowledge of the Company, conflicts with the valid
trade secret, trademark, trade name, copyright, patent, patent
<PAGE>

right or other Intangible Asset of any other person.

     2.13 Employee Matters.  There is no strike, work stoppage or labor dispute
          ----------------
with any union or group of employees pending or, to the knowledge of the
Company, threatened involving the Company.

     2.14 Financial Statements.  The financial statements included in the '34
          --------------------
Act Filings, including in each case the related notes, fairly present the
financial position of the Company as of the respective dates of said balance
sheets and the results of the operations of the Company for the respective
periods covered by said statements of operations and retained earnings and
changes in financial position, and have been prepared in accordance with
generally accepted accounting principles consistently applied by the Company
throughout the periods involved and the Company has no knowledge of any material
liabilities contingent or otherwise, not reflected in said balance sheet as of
said date or in the '34 Act Filings.

     2.15 No Change of Control.  Consummation of the transactions contemplated
          --------------------
by this Agreement will not constitute a "change of control" or "change in
control" or any other event of similar import as defined in any agreement to
which the Company is a party, and will not subject BLP to the provisions of
Sections 78.378 through 78.3793 or Sections 78.411 through 78.444 of the Nevada
Corporate law.

     2.16 No General Solicitation.  The sale of the Shares hereunder is exempt
          -----------------------
from the registration and prospectus delivery requirements of the Securities Act
of 1933, as amended (the "Securities Act").  In connection with the issuance and
sale of the Shares, no form of general solicitation or general advertising was
used by the Company or any of its representatives including, but not limited to
advertisements, articles, notices or other communications published in any
newspaper, magazine or similar medium or broadcast over television or radio, or
any seminar or meeting whose attendees had been invited by any general
solicitation or general advertising.

     2.17 Litigation.  There is no action, suit, proceeding or, to the knowledge
          ----------
of the Company, investigation pending or, to the Company's knowledge, currently
threatened against the Company which might result, either individually or in the
aggregate, in any material adverse changes in the material assets, condition,
affairs or prospects of the Company, financially or otherwise, nor is the
Company aware that there is any basis for any of the foregoing.

     2.18 Filings.  The Company has timely filed all reports, registration
          -------
statements and other documents required to be filed by it with the SEC under the
Securities Act or the '34 Act, including without limitation the Company's
Quarterly Report on Form 10-Q for the fiscal quarter ended June 30, 1996, and
Annual Report on Form 10-K for the fiscal year ended December 31, 1995.  As of
its filing date, no such report or statement contained or contains any untrue
statement of a material fact or omits to state any material fact necessary in
order to make the statements made therein, in the light of the circumstances
under which they were made, not misleading as of the date made.

     2.19 Disclosure.  This Agreement, including schedules and exhibits, does
          ----------
not contain any untrue statement of a material fact or omit to state a material
fact necessary to make the
<PAGE>

statements made in this Agreement not misleading in light of the circumstances
under which they were made.

     3.   Representation of BLP.  BLP represents and warrants to the Company
          ---------------------
that:

     3.1  Investment.  BLP is acquiring the Shares for its own account for
          ----------
investment and not with a view to, or for sale in connection with, any
distribution thereof which would be in violation of the securities laws of the
United States, and any sale, transfer or other disposition of any Shares will be
made in compliance with all applicable provisions of the Securities Act and the
rules and regulations promulgated thereunder.

     3.2  Authority.  BLP has full power and authority to enter into, to perform
          ---------
under and comply with this Agreement and this Agreement constitutes the valid
and binding obligation of BLP enforceable in accordance with its terms, except
as may be limited by bankruptcy, insolvency, reorganization, moratorium or other
laws limiting the rights and remedies of  creditors generally and as may be
limited by general equitable principles.

     3.3  Independent Investigation.  BLP, in entering into this Agreement, has
          -------------------------
relied upon an independent investigation made by it and its representatives, if
any.  In making its investment decision to purchase the Shares, BLP is not
relying on any oral or written representations or assurances from the Company or
any of its employees, representatives or agents other than as set forth in this
Agreement.

     3.4  Accredited Investor.  BLP is an Accredited Investor as such term is
          -------------------
defined in the Securities Act, Rule 501(a).

     3.5  Non-Contravention.  The execution of, performance under and compliance
          -----------------
with this Agreement by BLP will not violate any provision of law and will not
conflict with or result in any breach of any of the terms, conditions, or
provisions of, or constitute, with or without the passage of time or the giving
of notice, a default under, or require a consent or waiver under, any indenture,
lease, agreement or other instrument to which BLP is a party or by which BLP or
any of its properties is bound except as would not have a material adverse
effect on the business, financial condition or results of operations of BLP.

     4.   Closing Conditions.  The obligations of each of the parties hereto
          ------------------
shall be subject to the satisfaction or waiver of each of the following
conditions:

     4.1  No Judgments or Actions.  There shall not be in effect a judgment,
          -----------------------
order or decree of a court of competent jurisdiction that prevents or delays the
consummation of the transactions contemplated hereby.  There shall not be any
actions, suits, investigations or proceedings pending or to the best knowledge
of the Company threatened against or affecting the Company or its properties
which, if adversely determined, would interfere with or adversely affect the
issuance of the Shares.

     4.2  Representations and Warranties.  The representations and warranties of
          ------------------------------
the other party hereto shall have been true when made and shall be true at and
as of the Closing as though made at and as of such date.
<PAGE>

     4.3  Approvals and Consents.  The Company shall have received all consents
          ----------------------
and approvals required in connection with the issuance of the Shares, including,
without limitation, those required by law, any contract or agreement to which
the Company is a party or any securities exchange on which the Company's
securities are listed or quoted.

     4.4  Officer's Certificate.  The Company shall have delivered the
          ---------------------
certificate of an executive officer of the Company to the effect that the
foregoing conditions to closing have, to such officer's best knowledge, been
satisfied.

     4.5  Legal Opinion.  A favorable written opinion of Eilenberg & Zivian,
          -------------
counsel to the Company, in a form satisfactory to BLP shall have been delivered
with respect to due authorization and valid issuance of the Shares, due
execution and enforceability of this Agreement, and good standing of the
Company.  Such counsel may rely as to matters of Nevada law on an opinion of
local counsel.

     4.6  Satisfactory Proceedings.  All proceedings taken in connection with
          ------------------------
the sale of the Shares and all documents relating thereto shall be satisfactory
in form and substance to BLP.  BLP shall have received copies of such documents
as it may request in connection with the Closing, or as a basis for the Closing
opinions, all in form and substance satisfactory to BLP.

     5.   Adjustment Upon Changes in Capitalization.  In the event of any change
          -----------------------------------------
in the Company's common stock prior to the Closing by reason of stock dividends,
split-ups, recapitalizations, combinations, exchanges of shares or the like, the
number of Shares and the purchase price per Share provided for hereunder shall
be adjusted proportionately.  In addition, the Company agrees that it shall not
issue shares of Common Stock at a price which is below fair value for such
shares as determined in good faith by, and the informed judgement of, the Board
of Directors of the Company.

     6.   BLP Covenants.  BLP covenants that:
          -------------

     6.1  Press Release.  BLP shall not issue any press release relating to the
          -------------
sale and acquisition of the Shares and related matters contemplated hereby
without the prior approval of the Company.

     6.2  Confidentiality.  BLP acknowledges and agrees that any information or
          ---------------
data it has acquired from the Company, not otherwise properly in the public
domain, was received in confidence.  BLP agrees (and agrees to cause his
officers, employees, agents, representatives and directors) not to, without the
Company's consent, divulge, communicate or disclose any confidential information
it has obtained prior to the date hereof with respect to the Company, except as
may be required by law, or as may be necessary to disclose to its attorneys,
accountants and other advisors (but only to the extent such individuals agree to
be bound by the confidentiality provisions hereof).  BLP's obligation under this
Section 6.2 shall cease as to any information or data which after its
acquisition from the Company became or becomes generally available to the public
otherwise than as a result of a disclosure by BLP or anyone to whom it, directly
or indirectly, transmits such information or data in violation of this Section
6.2.
<PAGE>

     7.   Registration Rights.  BLP shall have the following registration rights
          -------------------
with respect to the Shares:

     7.1  Certain Definitions.  As used in this Section 7, the following terms
          -------------------
shall have the following meanings:

     (a) The terms "Register", "Registered" and "Registration" refer to a
                    --------    ----------       ------------
registration effected by preparing and filing a registration statement in
compliance with the Securities Act ("Registration Statement") for the purpose of
effecting a public sale of securities, and the declaration or ordering of the
effectiveness of such Registration Statement.

     (b) "Registration Expenses" shall mean all expenses incurred by the Company
          ---------------------
in complying with this Section 7, including, without limitation, all federal and
state registration, qualification and filing fees, printing expenses, fees and
disbursements of counsel for the Company, Blue Sky fees and expenses, and the
expense of any special audits incident to or required by any such Registration.

     (c) "Selling Expenses" shall mean all underwriting discounts and selling
          ----------------
commissions applicable to the sale of Shares pursuant to a Registration and all
fees and disbursements of counsel for BLP.

     (d) "Shares" for purposes of this Section 7 shall include any securities of
          ------
the Company issued to BLP on account of the Shares, whether by way of stock
split or recapitalization or as a dividend on the Shares.

     7.2  Registration.
          ------------

     (a)   Piggyback Registration.  From and after the date of this Agreement,
           -----------------------
and subject to the applicable provisions of Section 7.3 below, BLP shall have
the right, at any time the Company shall commence the preparation and filing of
a Registration Statement to Register its securities to include in the offering
such amount of Shares as BLP shall request to be included by written notice to
the Company received within five (5) business days after receipt of the
Company's notice of such Registration.  The Company shall give BLP prompt notice
of the date on which it commences the preparation and filing of such a
Registration Statement.

     (b) Demand Registration. If upon the later to occur of (i) the first
         -------------------
commercial sale of a drug product containing Loteprednol Etabonate in any
country outside of the United States, or (ii) the second anniversary of this
Agreement, BLP cannot sell or otherwise transfer the Shares after exercising
diligent efforts for six (6) months, pursuant to Rule 144 promulgated under the
Securities Act, and a similar exemption under applicable state securities laws,
BLP shall have the right, at any time subsequent to the later of the dates set
forth above, to make one (1) request that the Company register any Shares
specified in the notice and not previously registered under the Securities Act
on any form which may be used for such Registration as determined in good faith
by the Company, and under other relevant securities laws, for disposition in
accordance with methods stated in the notice, and otherwise subject to the
applicable provisions of Section 7.3 below.
<PAGE>

     (c)  Notice of Registration.  Each request delivered by BLP pursuant to
          ----------------------
Section 7.2(a) or (b) above shall: (i) specify the amount of Shares intended to
be offered and sold by BLP; and (ii) contain the undertaking of BLP to provide
all such information and materials and take all such action as may be required
in order to permit the Company to comply with all applicable requirements of the
Securities Act, the SEC and state securities and "blue sky" laws and to obtain
acceleration of the effective date of the Registration Statement, and (iii) if
applicable, specify the intended method of disposition.

     7.3  Limitations on Registrations.  Notwithstanding anything contained
          ----------------------------
herein to the contrary, the obligations of the Company to cause Shares to be
registered pursuant to Sections 7.2(a) and 7.2(b) above are subject to each of
the following limitations, conditions and qualifications, as applicable:

     (a)  The Company shall not be required to give notice or include Shares in
any registration pursuant to Section 7.2(a) if the proposed Registration is
primarily:  (i) a registration of a stock option, thrift, employee benefit or
compensation plan or of securities issued or issuable pursuant to any such plan;
(ii) a registration of securities proposed to be issued in connection with a
dividend reinvestment and stock purchase plan or customer stock purchase plan;
(iii) a registration of securities proposed to be issued in exchange for
securities or assets of, or in connection with a merger or consolidation with,
another corporation or other entity; or (iv) a registration of securities which
is solely a combination of any of the above.

     (b)  The Company shall not be obligated to give notice or include Shares in
any registration pursuant to Section 7.2(b) during the period starting with the
date thirty (30) days prior to the Company's estimated date of filing of, and
ending on a date six months following the effective date of, a registration
pertaining to an underwritten public offering of securities for the account of
the Company, provided that the Company is actively employing in good faith all
reasonable efforts to cause such registration statement to become effective and
that the Company's estimates of the date of filing of such registration
statement is made in good faith.

     (c)  If (i) there is material non-public information regarding the Company
which the Board of Directors of the Company determines in good faith, based upon
an informed judgement, not to be in the Company's best interest to disclose and
which the Company is not otherwise required to disclose, or (ii) there is a
significant business opportunity available to the Company which the Board
determines in good faith, based upon an informed judgement, not to be in the
Company's best interest to disclose and which the Company is not otherwise
required to disclose, or (iii) there is a significant business opportunity
available to the Company and the Board determines in good faith, based upon an
informed judgement, that the Company's ability to pursue such opportunity would
be materially and adversely affected by a registered public offering of the
Common Stock, then the Company may postpone filing a registration statement
requested pursuant to Section 7.2(b) for a period not to exceed 150 days,
provided that the Company may not postpone its obligation under this subpart
more than once every 12 months.

     (d)  If (i) BLP requests inclusion of any Shares in a registration
statement pursuant to Section 7.2(a) of this Agreement, (ii) the offering
proposed to be made is to be an underwritten public offering, and (iii) the
managing underwriters of such public offering furnish a written opinion that the
total amount of Common Stock to be included in such offering would exceed
<PAGE>

the maximum amount of Common Stock (as specified in such opinion) which can be
marketed at a price reasonably related to the then current market value of the
Common Stock and without materially and adversely affecting such offering, then
in such case the rights of BLP, of the holders of other securities having the
right to include such securities in such registration and of the Company to
participate in such offering shall be in the following order of priority: First:
the Company; and then Second: the holders (including BLP) shall be entitled to
participate in such offering, pro rata among themselves in accordance with the
number of shares of Common Stock which each such holder has requested be
registered.

     (e) In connection with any offering involving an underwriting of Shares
pursuant to Section 7.2(a) of this Agreement, the Company shall not be required
to include any of the Shares of BLP in such offering unless BLP agrees to the
terms of the underwriting agreed to between the Company and the underwriter or
underwriters selected by the Company, provided that no such agreement shall add
to the indemnities or affect the priorities set forth in this Agreement.

     (f)  The Company may, in its sole discretion, without the consent of BLP
and without liability to BLP for such action, withdraw a Registration Statement
at any time described in Section 7.2(a).

     7.4  Blue Sky.  The Company will exercise its best efforts to Register and
          --------
qualify the Shares included in the Registration Statement under such other
securities or Blue Sky laws of such jurisdictions as shall be reasonably
requested by BLP for the distribution of such securities; provided, however,
that the Company shall not be required to qualify to do business, to file a
general consent to service of process, or to subject itself to taxation in any
state or jurisdiction in which it is not now so qualified or taxed.

     7.5  Expenses of Registration.  All Registration Expenses incurred in
          ------------------------
connection with the Registration Statement pursuant to Section 7.2 shall be
borne by the Company.  All Selling Expenses shall be borne by BLP.  Fees and
expenses of counsel engaged by BLP for purposes of any Registration shall be
borne by BLP.

     7.5  Registration Procedures.
          -----------------------

     (a) Advice By the Company.  The Company will keep BLP advised as to the
         ---------------------
initiation and completion of any Registration Statement.  At its expense the
Company will (i) furnish such number of prospectuses (including preliminary
prospectuses) and other documents as BLP from time to time may reasonably
request; and (ii) furnish to BLP, upon the effectiveness of the Registration
Statement and upon each change in facts set forth in such memorandum, a
memorandum of counsel advising as to the status of its registration and
qualification of its Shares under the securities or Blue Sky laws of those
jurisdictions reasonably requested by BLP pursuant to this Section 7.  In
addition, the obligation of the Company to maintain the effectiveness of any
Registration Statement shall be suspended with respect to any Shares held by BLP
at any time following the sale of such Shares pursuant to Rule 144(k) or through
the Registration Statement.

     (b) Amendments.  The Company will promptly prepare and file with the SEC
         ----------
such amendments and prospectus supplements, including post-effective amendments,
to the
<PAGE>

Registration Statement as the Company determines may be necessary or
appropriate, and use its best efforts to have such post-effective amendments
declared effective as promptly as practicable; cause the related prospectus to
be supplemented by any prospectus supplement, and as so supplemented, to be
filed with the SEC; and notify BLP promptly when a prospectus, any prospectus
supplement or post-effective amendment must be filed (because the Registration
Statement has become inaccurate or otherwise) or has been filed and, with
respect to any post-effective amendment, when the same has become effective.

     7.6  Information Furnished by BLP.  It shall be a condition precedent to
          ----------------------------
the Company's obligations to register the Shares under this Agreement that BLP
furnish to the Company in writing such information regarding BLP and the
distribution proposed by BLP as the Company may reasonably request.

     7.7  Indemnification.
          ---------------

     (a) The Company's Indemnification.  The Company will indemnify BLP and its
         -----------------------------
officers and directors, and each person controlling BLP, with respect to which
Registration, qualification or compliance has been effected pursuant to this
Agreement, against all claims, losses, damages or liabilities (or actions in
respect thereof) to the extent such claims, losses, damages or liabilities arise
out of or are based upon any untrue statement (or alleged untrue statement) of a
material fact contained in any prospectus or any related Registration Statement
incident to any such Registration, qualification or compliance, or any omission
(or alleged omission) to state therein a material fact required to be stated
therein or necessary to make the statements therein not misleading, or any
violation by the Company of any rule or regulation promulgated under the 1933
Act applicable to the Company and relating to action or inaction required of the
Company in connection with any such Registration; and the Company will reimburse
BLP, and each person who controls BLP, for any legal and any other expenses
reasonably incurred in connection with investigating or defending any such
claim, loss, damage, liability or action; provided, however, that the indemnity
contained in this Section shall not apply to amounts paid in settlement of any
such claim, loss, damage, liability or action if settlement is effected without
the consent of the Company (which consent shall not unreasonably be withheld and
may not be withheld unless the Company has acknowledged in writing BLP's right
to indemnity under such claim); and provided, further, that the Company will not
be liable in any such case to the extent that any such claim, loss, damage,
liability or expense arises out of or is based upon any untrue statement or
omission based upon written information furnished to the Company by BLP, or
controlling person and stated in writing to be for use in connection with the
offering of securities of the Company.  Notwithstanding the above, the foregoing
indemnity is subject to the condition that, insofar as it relates to any such
untrue statement, alleged untrue statement, omission or alleged omission made in
a preliminary prospectus on file with the SEC at the time the Registration
Statement becomes effective or a prospectus filed with the SEC pursuant to Rule
424(b) (the "Final Prospectus"), such indemnity agreement shall not inure to the
benefit of BLP, if (i) a copy of the Final Prospectus was not furnished to the
person asserting the loss, liability, claim or damage at or prior to the time
such action is required by the 1933 Act, (ii) the Final Prospectus corrected the
untrue statement or omission or alleged untrue statement or omission, and (iii)
BLP or an agent of BLP had an affirmative obligation under applicable laws,
rules or regulations to deliver the Final Prospectus to the person asserting the
loss, liability, claim or damage.
<PAGE>

     (b) BLP's Indemnification.  BLP will indemnify the Company, each of its
         ---------------------
directors and officers, each person who controls the Company within the meaning
of the 1933 Act, against all claims, losses, damages and liabilities (or actions
in respect thereof) arising out of or based upon (i) any untrue statement (or
alleged untrue statement) of a material fact contained in such Registration
Statement or related prospectus, or any omission (or alleged omission) to state
therein a material fact required to be stated therein or necessary to make the
statements therein not misleading, or (ii) the failure by BLP to deliver a Final
Prospectus to any person as required by any rule or regulation promulgated under
the 1933 Act, and will reimburse the Company, such directors, officers, or
control persons for any legal and any other expenses reasonably incurred in
connection with investigating or defending any such claim, loss, damage,
liability or action, in each case to the extent, but only to the extent, that
such untrue statement (or alleged untrue statement) or omission (or alleged
omission) is made in the Registration Statement or prospectus in reliance upon
and in conformity with written information furnished to the Company by BLP and
stated to be specifically for use in connection with the offering of the
Company; provided, however, that BLP's liability under this Section shall not
         --------
exceed BLP's proceeds from the offering of its Shares made in connection with
such Registration.

     (c) Indemnification Procedure.  Promptly after receipt by an indemnified
         -------------------------
party under this Section 7 of notice of the commencement of any action, such
indemnified party will, if a claim in respect thereof is to be made against an
indemnifying party under this Section 7, notify the indemnifying party in
writing of the commencement thereof and generally summarize such action.  The
indemnifying party shall have the right to participate in and to assume the
defense of such claim, and shall be entitled to select counsel for the defense
of such claim with the approval of the party entitled to indemnification, which
approval shall not be unreasonably withheld.  Notwithstanding the foregoing, the
party entitled to indemnification shall have the right to employ separate
counsel (reasonably satisfactory to the indemnifying party) to participate in
the defense thereof, but the fees and expenses of such counsel shall be the
expense of such indemnified party unless the named parties to such action or
proceedings include both the indemnifying party and the indemnified party and
the indemnifying party or the indemnified party shall have been advised by
counsel that there are one or more legal defenses available to it which are
different from or additional to those available to the indemnifying party (in
which case, if the indemnified party notifies the indemnifying party in writing
that it elects to employ separate counsel at the reasonable expense of the
indemnifying party, the indemnifying party shall not have the right to assume
the defense of such action or proceeding on behalf of the indemnified party).

     (d) Contribution.  If the indemnification provided for in this Section 7.7
         ------------
from an indemnifying party is unavailable to an indemnified party hereunder in
respect to any losses, claims, damages, liabilities or expenses referred to
herein, then the indemnifying party, in lieu of indemnifying such indemnified
party, shall contribute to the amount paid or payable by such indemnified party
as a result of such losses, claims, damages, liabilities or expenses in such
proportion as is appropriate to reflect the relative fault of the indemnifying
party and indemnified party in connection with the statements or omissions which
result in such losses, claims, damages, liabilities or expenses, as well as any
other relevant equitable considerations.  The relative fault of such
indemnifying party and indemnified party shall be determined by reference to,
among other things, whether the untrue or alleged untrue statement of a material
fact or the omission or alleged omission to state a material fact relates to
information supplied by such
<PAGE>

indemnifying party or indemnified party and the parties' relative intent,
knowledge, access to information supplied by such indemnifying party or
indemnified party and opportunity to correct or prevent such statement or
omission.  The amount paid or payable by a party as a result of the losses,
claims, damages, liabilities and expenses referred to above shall be deemed to
include any legal or other fees or expenses reasonably incurred by such party in
connection with investigating or defending any action, suit, proceeding or
claim.

     7.8  No-Action Letter or Opinion of Counsel in Lieu of Registration.
          --------------------------------------------------------------
Notwithstanding anything else in this Agreement, if the Company shall have
obtained from the SEC a "no-action" letter in which the SEC has indicated that
it will take no action if, without Registration under the 1933 Act, BLP disposes
of Shares covered by any request for Registration made under this Section 7 in
the specific manner in BLP proposes to dispose of the Shares included in such
request (such as including, without limitation, inclusion of such Shares in an
underwriting initiated by the Company), or if in the opinion of counsel for the
Company concurred in by counsel for BLP, which concurrence shall not be
unreasonably withheld, no Registration under the 1933 Act is required in
connection with such disposition, due to the applicability of Rule 144(k) as
promulgated under the 1933 Act (or any successor provision), the Shares included
in such request shall not be eligible for Registration under this Agreement;
provided, however, that any Shares not so disposed of shall be eligible for
Registration in accordance with the terms of this Agreement with respect to
other proposed dispositions to which this Section 7.8 does not apply.  In
addition, the obligation of the Company to file or maintain the effectiveness of
any Registration Statement shall be suspended with respect to any Shares held by
BLP following such time.

     8.   Miscellaneous.
          -------------

     8.1  Amendments.  This Agreement may not be modified, amended, altered or
          ----------
supplemented except upon the execution and delivery of a written agreement
executed by the parties hereto.

     8.2  Termination.  This Agreement may be terminated by mutual consent of
          -----------
the parties hereto or by either party if the other party breaches this
Agreement.

     8.3  Notices.  All notices, requests, claims, demands and other
          -------
communications hereunder shall be in writing and shall be given (and shall be
deemed to have been duly received if so given) by hand delivery, by cable,
telegraph or telex, Federal Express or other recognized overnight courier by
mail (registered or certified mail, postage prepaid, return receipt requested)
or by facsimile transmission to the respective parties as follows:

          If to BLP to:

          Bausch & Lomb Pharmaceuticals, Inc.
          8500 Hidden River Parkway
          Tampa, FL 33637
          Attn: Mark Tomaino, Esq.
          Fax No. 716-338-8706
<PAGE>

          If to the Company, to:

          Pharmos Corporation
          2 Innovation Drive
          Alachua, FL 32615
          Fax No. 904-462-5401

          With a copy to:

          Adam D. Eilenberg, Esquire
          Eilenberg & Zivian
          666 3rd Avenue, 30th Floor
          New York, NY 10017
          Fax No. 212-986-2399

or to such other address as either party may have furnished to the other in
writing in accordance herewith, except that notices of change of address shall
only be effective upon receipt.

     8.4  Survival of Representations and Warranties.  All representations and
          ------------------------------------------
warranties contained herein or made in writing by the Company or BLP in
connection herewith shall survive the execution and delivery of this Agreement,
the sale and purchase of the Shares and any disposition thereof, regardless of
any investigation made by or on behalf of BLP or the Company, as the case may
be.

     8.5  Indemnification.  Each of the Company and BLP agrees to indemnify and
          ---------------
to hold the other harmless against and in respect of any and all losses,
damages, costs and expenses, including, without limitation, reasonable
attorneys' fees, as incurred by the indemnified party, by reasons of a breach of
any of the express representations, warranties or covenants and agreements of
the other made in this Agreement, or otherwise on account of the transactions
contemplated herein except that BLP shall only be liable to the Company for
breaches of representations and warranties with respect to itself only.

     8.6  Governing Law.  This Agreement shall be governed by and construed in
          -------------
accordance with the substantive law of the State of New York without giving
effect to the principles of conflict of laws thereof.

     8.7  Counterparts.  This Agreement may be executed in several counterparts,
          ------------
each of which shall be an original, but all of which together shall constitute
one and the same agreement.

     8.8  Trading Market; Reports.  The Company shall use best efforts to ensure
          -----------------------
that its Common Stock is listed and eligible for trading on the NASDAQ stock
market or a national securities exchange until such time as BLP has resold all
of the Shares purchased hereunder.



                             *****END OF TEXT*****
<PAGE>

     IN WITNESS WHEREOF, the parties have caused this Stock Purchase Agreement
to be duly executed on the day and year first above written.



                              BAUSCH & LOMB PHARMACEUTICALS, INC


                              By:  /s/  Alan P. Damper
                                 ----------------------------------------------

                              Title:    President
                                    -------------------------------------------


                              PHARMOS CORPORATION


                              By: /s/  Gad Riesenfeld
                                 ----------------------------------------------

                              Title:   Exec. V.P. and C.O.O.
                                    -------------------------------------------