1
                                                                     EXHIBIT 4.3


THIS WARRANT AND THE SHARES ISSUABLE HEREUNDER HAVE NOT BEEN REGISTERED UNDER 
THE SECURITIES ACT OF 1933, AS AMENDED, AND MAY NOT BE SOLD, PLEDGED, OR 
OTHERWISE TRANSFERRED WITHOUT AN EFFECTIVE REGISTRATION THEREOF UNDER SUCH ACT 
OR PURSUANT TO RULE 144 OR AN OPINION OF COUNSEL REASONABLY SATISFACTORY TO THE 
CORPORATION AND ITS COUNSEL, THAT SUCH REGISTRATION IS NOT REQUIRED.

                           WARRANT TO PURCHASE STOCK

Corporation: ADVANCED POLYMER SYSTEMS, INC., a Delaware corporation
Number of Shares:       32,500
Class of Stock:         Common
Initial Exercise Price: $7.00 per share
Issue Date:             September 27, 1995
Expiration Date:        March 27, 2000

      THIS WARRANT CERTIFIES THAT, for the agreed upon value of $1.00 and for 
other good and valuable consideration, VENTURE LENDING ("Holder") is entitled to
purchase the number of fully paid and nonassessable shares of the class of
securities (the "Shares") of the corporation (the "Company") at the initial
exercise price per Share (the "Warrant Price") all as set forth above and as
adjusted pursuant to Article 2 of this Warrant, subject to the provisions and
upon the terms and conditions set forth of this Warrant.

ARTICLE 1.  EXERCISE

        1.1     Method of Exercise. Holder may exercise this Warrant by 
delivering a duly executed Notice of Exercise in substantially the form attached
as Appendix 1 to the principal office of the Company. Unless Holder is
exercising the conversion right set forth in Section 1.2, Holder shall also
deliver to the Company a check for the aggregate Warrant Price for the Shares
being purchased.

        1.2    Conversion Right. In lieu of exercising this Warrant as 
specified in Section 1.1, Holder may from time to time convert this Warrant, in
whole or in part, into a number of Shares determined by dividing (a) the
aggregate fair market value of the Shares or other securities otherwise issuable
upon exercise of this Warrant minus the aggregate Warrant Price of such Shares
by (b) the fair market value of one Share. The fair market value of the Shares
shall be determined pursuant Section 1.4.

        1.3    Fair Market Value. If the Shares are traded in a public market,
the fair market value of the Shares shall be the closing price of the Shares (or
the closing price of the Company's stock into which the Shares are convertible)
reported for the business day immediately before Holder delivers its Notice of
Exercise to the Company. If the Shares are not traded in a public market, the
Board of Directors of the Company shall determine fair market value in its
reasonable good faith judgment. The foregoing notwithstanding, if Holder advises
the Board of Directors in writing that Holder disagrees with such determination,
then the Company and Holder shall promptly agree upon a reputable investment
banking firm to undertake such valuation. If the valuation of such investment
banking firm is greater than that determined by the Board of Directors, then all
fees and
 
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expenses of such investment banking firm shall be paid by the Company. In all 
other circumstances, such fees and expenses shall be paid by Holder.

        1.4    Delivery of Certificate and New Warrant. Promptly after Holder 
exercises or converts this Warrant, the Company shall deliver to Holder 
certificates for the Shares acquired and, if this Warrant has not been fully 
exercised or converted and has not expired, a new Warrant representing the 
Shares not so acquired.

        1.5    Replacement of Warrants. On receipt of evidence reasonably 
satisfactory to the Company of the loss, theft, destruction or mutilation of 
this Warrant and, in the case of loss, theft or destruction, on delivery of an
indemnity agreement reasonably satisfactory in form and amount to the Company
or, in case of mutilation, or surrender and cancellation of this Warrant, the
Company at its expense shall execute and deliver, in lieu of this Warrant, a 
new warrant of like tenor.

        1.6    Repurchase on Sale, Merger, or Consolidation of the Company.

               1.6.1  "Acquisition". For the purpose of this Warrant,
"Acquisition" means any sale, license, or other disposition of all or 
substantially all of the assets of the Company, or any reorganization,
consolidation, or merger of the Company where the holders of the Company's 
securities before the transaction beneficially own less than 50% of the
outstanding voting securities of the surviving entity after the transaction.

        1.6.2  Assumption of Warrant. If upon the closing of any Acquisition 
the successor entity assumes the obligations of this Warrant, then this Warrant 
shall be exercisable for the same securities, cash, and property as would be
payable for the Shares issuable upon exercise of the unexercised portion of 
this Warrant as if such Shares were outstanding on the record date for the
Acquisition and subsequent closing. The Warrant Price shall be adjusted
accordingly.

        1.6.3  Nonassumption. If upon the closing of any Acquisition the 
successor entity does not assume the obligations of his Warrant and Holder has 
not otherwise exercised this Warrant in full, then the unexercised portion of 
this Warrant shall be deemed to have been automatically converted pursuant to 
Section 1.2 and thereafter Holder shall participate in the acquisition on the 
same terms as other holders of the same class of securities of the Company.

        1.6.4  Purchase Right. Notwithstanding the foregoing, at the election 
of Holder, the Company shall purchase the unexercised portion of this Warrant 
for cash upon the closing of any Acquisition for an amount equal to (a) the 
fair market value of any consideration that would have been received by Holder 
in consideration of the Shares had Holder exercised the unexercised portion of 
this Warrant immediately before the record date for determining the 
shareholders entitled to participate in the proceeds of the Acquisition, less 
(b) the aggregate Warrant Price of the Shares, but in no event less than zero.

ARTICLE 2.  ADJUSTMENTS TO THE SHARES

        2.1    Stock Dividends, Splits, Etc. If the Company declares or pays a 
dividend on its common stock (or the Shares if the Shares are securities other 
than common stock) payable in common stock, or other securities, subdivides the 
outstanding common


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stock into a greater amount of common stock, or, if the Shares are securities 
other than common stock, subdivides the Shares in a transaction that increases 
the amount of common stock into which the Shares are convertible, then upon 
exercise of this Warrant, for each Share acquired, Holder shall receive, 
without cost to Holder, the total number and kind of securities to which Holder 
would have been entitled had Holder owned the Shares of record as of the date 
the dividend or subdivision occurred.

        2.2    Reclassification, Exchange or Substitution. Upon any 
reclassification, exchange, substitution, or other event that results in a 
change of the number and/or class of the securities issuable upon exercise or 
conversion of this Warrant, Holder shall be entitled to receive, upon exercise 
or conversion of this Warrant, the number and kind of securities and property 
that Holder would have received for the Shares if this Warrant had been 
exercised immediately before such reclassification, exchange, substitution, or 
other event. Such an event shall include any automatic conversion of the 
outstanding or issuable securities of the Company of the same class or series 
as the Shares to common stock pursuant to the terms of the Company's Articles 
of Incorporation upon the closing of a registered public offering of the
Company's common stock. The Company or its successor shall promptly issue to
Holder a new Warrant for such new securities or other property. The new Warrant
shall provide for adjustments which shall be as nearly equivalent as may be
practicable to the adjustments provided for in this Article 2 including, without
limitation, adjustments to the Warrant Price and to the number of securities or
property issuable upon exercise of the new Warrant. The provisions of this
Section 2.2 shall similarly apply to successive reclassifications, exchanges,
substitutions, or other events.

        2.3    Adjustments for Combinations, Etc. If the outstanding Shares are 
combined or consolidated, by reclassification or otherwise, into a lesser 
number of shares, the Warrant Price shall be proportionately increased.

        2.4    Adjustments for Diluting Issuances. The Warrant Price and the 
number of Shares issuable upon exercise of this Warrant or, if the Shares are 
Preferred Stock, the number of shares of common stock issuable upon conversion 
of the Shares, shall be subject to adjustment, from time to time in the manner 
set forth on Exhibit A in the event of Diluting Issuances (as defined on 
Exhibit A).

        2.5    No Impairment. The Company shall not, by amendment of its 
Articles of Incorporation or through a reorganization, transfer of assets, 
consolidation, merger, dissolution, issue, or sale of securities or any other 
voluntary action, avoid or seek to avoid the observance or performance of any 
of the terms to be observed or performed under this Warrant by the Company, but 
shall at all times in good faith assist in carrying out of all the provisions 
of this Article 2 and in taking all such action as may be necessary or 
appropriate to protect Holder's rights under this Article against impairment. 
If the Company takes any action affecting the Shares or its common stock other 
than as described above that adversely affects Holder's rights under this 
Warrant, the Warrant Price shall be adjusted downward and the number of Shares 
issuable upon exercise of this Warrant shall be adjusted upward in such a 
manner that the aggregate Warrant Price of this Warrant is unchanged.

        2.6    Fractional Shares. No fractional Shares shall be issuable upon 
exercise or conversion of the Warrant and the number of Shares to be issued 
shall be rounded down to the nearest whole Share. If a fractional share 
interest arises upon any exercise or conversion of the Warrant, the Company 
shall eliminate such fractional share interest by


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paying Holder amount computed by multiplying the factional interest by the fair 
market value of a full share.

            2.7        Certificate as to Adjustments. Upon each adjustment of
the Warrant Price, the Company at its expense shall promptly compute such
adjustment, and furnish Holder with a certificate of its Chief Financial Officer
setting forth such adjustment and the facts upon which such adjustment is based.
The Company shall, upon written request, furnish Holder a certificate setting
forth the Warrant Price in effect upon the date thereof and the series of
adjustments leading to such Warrant Price.

ARTICLE 3.  REPRESENTATIONS AND COVENANTS OF THE COMPANY.

            3.1  Representations and Warranties. The Company hereby represents 
and warrants to the Holder as follows:

                 (a)  All Shares which may be issued upon the exercise of the 
purchase right represented by this Warrant, and all securities, if any, 
issuable upon conversion of the Shares, shall, upon issuance, be duly 
authorized, validly issued, fully paid and nonassessable, and free of any liens 
and encumbrances except for restrictions on transfer provided for herein or 
under applicable federal and state securities laws.

            3.2  Notice of Certain Events. If the Company proposes at any time 
(a) to declare any dividend or distribution upon its common stock, whether in 
cash, property, stock, or other securities and whether or not a regular cash 
dividend; (b) to offer for subscription pro rata to the holders of any class or 
series of its stock any additional shares of stock of any class or series or 
other rights; (c) to effect any reclassification or recapitalization of common 
stock; (d) to merge or consolidate with or into any other corporation, or sell, 
lease, license, or convey all or substantially all of its assets, or to 
liquidate, dissolve or wind up; or (e) offer holders of registration rights the 
opportunity to participate in an underwritten public offering of the company's 
securities for cash, then, in connection with each such event, the Company 
shall give Holder (1) at least 20 days prior written notice of the date on 
which a record will be taken for such dividend, distribution or subscription 
rights (and specifying the date on which the holders of common stock will be 
entitled thereto) or for determining rights to vote, if any, in respect of the 
matters referred to in (c) and (d) above; (2) in the case of the matters 
referred to in (c) and (d) above at lease 20 days prior written notice of the 
date when the same will take place (and specifying the date on which the 
holders of common stock will be entitled to exchange their common stock for 
securities or other property deliverable upon the occurrence of such event); 
and (3) in the case of the matter referred to in (e) above, the same notice as 
is given to the holders of such registration rights.

            3.3  Information Rights. So long as the Holder holds this Warrant 
and/or any of the Shares, the Company shall deliver to the Holder (a) promptly 
after mailing, copies of all notices or other written communications to the 
shareholders of the Company, (b) within ninety (90) days after the end of each 
fiscal year of the Company, the annual audited financial statements of the 
Company certified by independent public accountants of


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recognized standing and (c) within forty-five (45) days after the end of each 
of the first three quarters of each fiscal year, the Company's quarterly, 
unaudited financial statements.

        3.4 Registration Under Securities Act of 1933, as amended. The Company 
agrees that the Shares or, if the Shares are convertible into common stock of 
the Company, such common stock, shall be subject to the registration rights set 
forth on Exhibit B, if attached.

ARTICLE 4. MISCELLANEOUS

        4.1 Term; Notice of Expiration. This Warrant is exercisable, in whole 
or in part, at any time and from time to time on or before the Expiration Date 
set forth above. The Company shall give Holder written notice of Holder's right 
to exercise this Warrant in the form attached as Appendix 2 not more than 90 
days and not less than 30 days before the Expiration Date. If the notice is not 
so given, the Expiration Date shall automatically be extended until 30 days 
after the date the Company delivers the notice to Holder.

        4.2 Legends. This Warrant and the Shares (and the securities issuable, 
directly or indirectly, upon conversion of the Shares, if any) shall be 
imprinted with a legend in substantially the following form:

        THIS SECURITY HAS NOT BEEN REGISTERED UNDER THE SECURITIES
        ACT OF 1933, AS AMENDED, AND MAY NOT BE SOLD, PLEDGED OR
        OTHERWISE TRANSFERRED WITHOUT AN EFFECTIVE REGISTRATION
        THEREOF UNDER SUCH ACT OR PURSUANT TO RULE 144 OR AN
        OPINION OF COUNSEL REASONABLY SATISFACTORY TO THE
        CORPORATION AND ITS COUNSEL THAT SUCH REGISTRATION IS NOT
        REQUIRED.

        4.3 Compliance with Securities Laws on Transfer. This Warrant and the 
Shares issuable upon exercise this Warrant (and the securities issuable, 
directly or indirectly, upon conversion of the Shares, if any) may not be 
transferred or assigned in whole or in part without compliance with applicable 
federal and state securities laws by the transferor and the transferee 
(including, without limitation, the delivery of investment representation 
letters and legal opinions reasonably satisfactory to the Company, as 
reasonably requested by the Company). The Company shall not require Holder to 
provide an opinion of counsel if the transfer is to an affiliate of Holder or 
if there is no material question as to the availability of current information
as referenced in Rule 144(c), Holder represents that it has complied with Rule
144(d) and (e) in reasonable detail, the selling broker represents that it has
complied with Rule 144(f), and the Company is provided with a copy of Holder's
notice of proposed sale.

        4.4 Transfer Procedure. Subject to the provisions of Section 4.2, 
Holder may transfer all or part of this Warrant or the Shares issuable upon 
exercise of this Warrant (or the securities issuable, directly or indirectly, 
upon conversion of the Shares, if any) by giving the Company notice of the 
portion of the Warrant being transferred setting forth the name, address and 
taxpayer identification number of the transferee and surrendering this Warrant 
to the Company for reissuance to the transferee(s) (and Holder if applicable). 
Unless the Company is filing financial information with the SEC pursuant to the 
Securities Exchange

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Act of 1934, the Company shall have the right to refuse to transfer any portion 
of this Warrant to any person who directly competes with the Company.

        4.5 Notices. All notices and other communications from the Company to 
the Holder, or vice versa, shall be deemed delivered and effective when given 
personally or mailed by first-class registered or certified mail, postage 
prepaid, at such address as may have been furnished to the Company or the 
Holder, as the case may be, in writing by the Company or such holder from time 
to time.

        4.6 Waiver. This Warrant and any term hereof may be changed, waived, 
discharged or terminated only by an instrument in writing signed by the party 
against which enforcement of such change, waiver, discharge or termination 
is sought.

        4.7 Attorneys Fees. In the event of any dispute between the parties 
concerning the terms and provisions of this Warrant, the party prevailing in 
such dispute shall be entitled to collect from the other party all costs 
incurred in such dispute, including reasonable attorneys' fees.

        4.8 Governing Law. This Warrant shall be governed by and construed in 
accordance with the laws of the State of California, wihout giving effect to 
its principles regarding conflicts of law.

                                       "COMPANY"
                                       ADVANCED POLYMER SYSTEMS, INC.


                                          
                                       By /s/  JOHN J. MEAKEM, JR.

                                       Name   John J. Meakem, Jr.
                                                     (Print)

                                       Title: Chairman of the Board, President,
                                              or Vice President


                                       By /s/  MICHAEL P.J. O'CONNELL

                                       Name   Michael P.J. O'Connell
                                                      (Print)

                                       Title: Chief Financial Officer, Secretary
                                              Assistant Treasurer, or Assistant
                                              Secretary

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                                   APPENDIX 1

                               NOTICE OF EXERCISE


        1.  The undersigned hereby elects to purchase _________ shares of the 
Common Stock of ADVANCED POLYMER SYSTEMS, INC. pursuant to the terms of the 
attached Warrant, and tenders herewith payment of the purchase price of such 
shares in full.

        1.  The undersigned hereby elects to convert the attached Warrant into 
Shares/cash [strike one] in the manner specified in the Warrant. This 
conversion is exercised with respect to _________________________ of the Shares 
covered by the Warrant.

        [Strike paragraph that does not apply.]

        2.  Please issue a certificate or certificates representing said shares 
in the name of the undersigned or in such other name as is specified below:

                                Venture Lending
                                Three Palo Alto Square, Suite 150
                                Palo Alto, CA 94306

        3.  The undersigned represents it is acquiring the shares solely for 
its own account and not as a nominee for any other party and not with a view 
toward the resale or distribution thereof except in compliance with applicable 
securities laws.


                                _______________________________________________
                                (Signature)


___________________
   (Date)

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                                   APPENDIX 2

                     Notice that Warrant Is About to Expire

                            __________________, ____


Venture Lending
Three Palo Alto Square, Suite 150
Palo Alto, CA 94306

Attn: Chief Financial Officer


Dear: ______________________

        This is to advise you that the Warrant issued to you described below 
will expire on __________________, 19__.

        Issuer: ADVANCED POLYMER SYSTEMS, INC.

        Issue Date: September 27, 1995

        Class of Security Issuable: Common
        
        Exercise Price per Share: $7.00

        Number of Shares Issuable: 32,500

        Procedure for Exercise:


        Please contact [name of contact person at (phone number)] with any 
questions you may have concerning exercise of the Warrant. This is your only 
notice of pending expiration.

                                        _____________________________________
                                        (Name of Issuer)


                                        By __________________________________

                                        Its _________________________________

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                                   EXHIBIT A

                            Anti-Dilution Provisions

        In the event of the issuance (a "Diluting Issuance") by the Company, 
after the Issue Date of the Warrant, of securities at a price per share less 
than the Warrant Price, then the number of shares of common stock issuable 
upon conversion of the Shares, or if the Shares are common stock, the number
of Shares issuable upon exercise of the Warrant, shall be adjusted as a result
of Diluting Issuances in accordance with the Holder's standard form of Anti-
Dilution Agreement in effect on the Issue Date.

        Under no circumstances shall the aggregate Warrant Price payable
by the Holder upon exercise of the Warrant increase as a result of any
adjustment arising from a Diluting Issuance.

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                                   EXHIBIT B

                              Registration Rights

                                VENTURE LENDING

                         REGISTRATION RIGHTS AGREEMENT


        THIS REGISTRATION RIGHTS AGREEMENT is entered into as of September 27,
1995, by and between Venture Lending ("Purchaser") and the Company whose name
appears on the last page of this Agreement.


                                    RECITALS

        A.      Concurrently with the execution of this Agreement, the
Purchaser is purchasing from the Company a Warrant to Purchase Stock and
Warrant to Purchase Additional Stock (the "Warrants") pursuant to which
Purchaser has the right to acquire from the Company the Shares (as defined
in the Warrants).

        B.      By this Agreement, the Purchaser and the Company desire to
set forth the registration rights of the Shares all as provided herein.

                NOW, THEREFORE, in consideration of the mutual promises,
covenants and conditions hereinafter set forth, the parties hereto
mutually agree as follows:

        1.      Registration Rights.  The Company covenants and agrees
as follows:

                1.1     Definitions.  For purposes of this Section 1:

                        (a)  The term "register," "registered," and
"registration" refer to a registration effected by preparing and filing a 
registration statement or similar document in compliance with the Securities
Act of 1933, as amended (the "Securities Act"), and the declaration or
ordering of effectiveness of such registration statement or document;

                        (b)  the term "Registrable Securities" means 
(i) the Shares (if Common Stock) or all shares of Common Stock of the Company
issuable or issued upon conversion of the Shares and (ii) any Common Stock
of the Company issued as (or issuable upon the conversion or exercise of
any warrants, right or other security which is issued as) a dividend or 
other distribution with respect to, or in exchange for or in replacement of, 
any stock referred to in (i).

                        (c)  The terms "Holder" or "Holders" means the 
Purchaser or qualifying transferees under subsection 1.8 hereof who hold
Registrable Securities.

                        (d)  The term "SEC" means the Securities and
Exchange Commission.

                1.2     Company Registration.

                        (a)  Registration.  If at any time or from time to
time, the Company shall determine to register any of its securities, for
its own account or the account of any of its shareholders, other than a
registration on Form S-1 or S-8 relating solely to employee stock option or
purchase plans, or a registration on Form S-4 relating solely to an SEC
Rule 145 transaction, or a registration on any other form (other than Form
S-1, S-2, S-3 or S-18, or their successor forms) or any successor to

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such forms, which does not include substantially the same information as would
be required to be included in a registration statement covering the sale of
Registrable Securities, the Company will:

                        (i)     promptly give to each Holder written notice 
thereof (which shall include a list of the jurisdictions in which the Company 
intends to attempt to qualify such securities under the applicable blue sky or 
other state securities laws); and

                        (ii)    include in such registration (and compliance), 
and in any underwriting involved therein, all the Registrable Securities 
specified in a written request or requests, made within 30 days after receipt 
of such written notice from the Company, by any Holder or Holders, except as 
set forth in subsection 1.2(b) below.

                (b)     Underwriting.  If the registration of which the 
Company gives notice is for a registered public offering involving an 
underwriting, the Company shall so advise the Holders as a part of the written 
notice given pursuant to subsection 1.2(a)(i). In such event the right of any 
Holder to registration pursuant to this subsection 1.2 shall be conditioned 
upon such Holder's participation in such underwriting and the inclusion of such 
Holder's Registrable Securities in the underwriting to the extent provided 
herein. All Holders proposing to distribute their securities through such 
underwriting shall (together with the Company and the other shareholders 
distributing their securities through such underwriting) enter into an 
underwriting agreement in customary form with the underwriter or underwriters 
selected for such underwriting by the Company.

        1.3     Expenses of Registration.  All expenses incurred in connection 
with any registration, qualification or compliance pursuant to this Section 1 
including without limitation, all registration, filing and qualification fees, 
printing expenses, fees and disbursements of counsel for the Company and 
expenses of any special audits incidental to or required by such registration, 
shall be borne by the Company except the Company shall not be required to pay 
underwriters' fees, discounts or commissions relating to Registrable 
Securities. All expenses of any registered offering not otherwise borne by the 
Company shall be borne pro rata among the Holders participating in the offering 
and the Company.

        1.4     Registration Procedures.  In the case of each registration, 
qualification or compliance effected by the Company pursuant to this 
Registration Rights Agreement, the Company will keep each Holder participating 
therein advised in writing as to the initiation of each registration, 
qualification and compliance and as to the completion thereof. Except as 
otherwise provided in subsection 1.3, at its expense the Company will:

                (a)     Prepare and file with the SEC a registration statement 
with respect to such Registrable Securities and use its best efforts to cause 
such registration statement to become effective, and, upon the request of the 
Holders of a majority of the Registrable Securities registered thereunder, keep 
such registration statement effective for up to 120 days.

                (b)     Prepare and file with the SEC such amendments and 
supplements to such registration statement and the prospectus used in 
connection with such registration statement as may be necessary to comply with 
the provisions of the Securities Act with respect to the disposition of all 
securities covered by such registration statement.

                (c)     Furnish to the Holders such numbers of copies of a 
prospectus, including a preliminary prospectus, in conformity with the 
requirements of the Securities Act, and such other documents as they may 
reasonably request in order to facilitate the disposition of Registrable 
Securities owned by them.

                (d)     Use its best efforts to register and qualify the 
securities covered by such registration statement under such other securities 
or Blue Sky laws of such jurisdictions as shall be reasonably requested by the 
Holders, provided that the Company shall not be required in


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connection therewith or as a condition thereto to qualify to do business or to 
file a general consent to service of process in any such states or
jurisdictions.

                (e)  In the event of any underwritten public offering, enter 
into and perform its obligations under an underwriting agreement, in usual and 
customary form, with the managing underwriter of such offering. Each Holder 
participating in such underwriting shall also enter into and perform its 
obligations under such an agreement.

                (f)  Notify each Holder of Registrable Securities covered by 
such registration statement at any time when a prospectus relating thereto is 
required to be delivered under the Securities Act or the happening of any event 
as a result of which the prospectus included in such registration statement, as 
then in effect, includes an untrue statement of a material fact or omits 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 then
existing.

        1.5  Indemnification.

                (a)  The Company will indemnify each Holder of Registrable 
Securities and each of its officers, directors and partners, and each person 
controlling such Holder, with respect to which such registration, qualification 
or compliance has been effected pursuant to this Rights Agreement, and each 
underwriter, if any, and each person who controls any underwriter of the 
Registrable Securities held by or issuable to such Holder, against all claims, 
losses, expenses, damages and liabilities (or actions in respect thereto) 
arising out of or based on any untrue statement (or alleged untrue statement) 
of a material fact contained in any prospectus, offering circular or other 
document (including any related registration statement, notification or the 
like) incident to any such registration, qualification or compliance, or based 
on any omission (or alleged omission) to state therein a material fact 
required to be stated therein or necessary to make the statement therein not 
misleading, or any violation or alleged violation by the Company of the 
Securities Act, the Securities Exchange Act of 1934, as amended, ("Exchange 
Act") or any state securities law applicable to the Company or any rule or 
regulation promulgated under the Securities Act, the Exchange Act or any such 
state law and relating to action or inaction required of the Company in 
connection with any such registration, qualification of compliance, and will 
reimburse each such Holder, each of its officers, directors and partners, and 
each person controlling such Holder, each such underwriter and each person who 
controls any such underwriter, within a reasonable amount of time after 
incurred for any reasonable legal and any other expenses incurred in connection 
with investigating, defending or settling any such claim, loss, damage, 
liability or action; provided, however, that the indemnity agreement contained 
in this subsection 1.5(a) shall not apply to amounts paid in settlement of any 
such claim, loss, damage, liability, or action if such settlement is effected 
without the consent of the Company (which consent shall not be unreasonably 
withheld); and provided further, that the Company will not be liable in any 
such case to the extent that any such claim, loss, damage or liability arises 
out of or is based on any untrue statement or omission based upon written 
information furnished to the Company by an instrument duly executed by such 
Holder or underwriter specifically for use therein.

                (b)  Each Holder will, if Registrable Securities held by or 
issuable to such Holder are included in the securities as to which such 
registration, qualification or compliance is being effected, indemnify the 
Company, each of its directors and officers, each underwriter, if any, of the 
Company's securities covered by such a registration statement, each person who 
controls the Company within the meaning of the Securities Act, and each other 
such Holder, each of its officers, directors and partners and each person 
controlling such Holder, against all claims, losses, expenses, damages and 
liabilities (or actions in respect thereof) arising out of or based on any 
untrue statement (or alleged untrue statement) of a material fact contained in 
any such registration statement, prospectus, offering circular or other 
document, 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, and will reimburse the Company, such Holders, such directors, 
officers, partners, persons

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or underwriters for any reasonable legal or any other expenses incurred in 
connection with investigating, defending or settling 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 such registration statement, prospectus, offering
circular or other document in reliance upon and in conformity with written
information furnished to the Company by an instrument duly executed by such
Holder specifically for use therein; provided, however, that the indemnity
agreement contained in this subsection 1.5(b) shall not apply to amounts paid in
settlement of any such claim, loss, damage, liability or action if such 
settlement is effected without the consent of the Holder, (which consent shall
not be unreasonably withheld); and provided further, that the total amount for
which any Holder shall be liable under this subsection 1.5(b) shall not in any
event exceed the aggregate proceeds received by such Holder from the sale of
Registrable Securities held by such Holder in such registration.

                (c) Each party entitled to indemnification under this 
subsection 1.5 (the "Indemnified Party") shall give notice to the party 
required to provide indemnification (the "Indemnifying Party") promptly after 
such Indemnified Party has actual knowledge of any claim as to which indemnity 
may be sought, and shall permit the Indemnifying Party to assume the defense of 
any such claim or any litigation resulting therefrom; provided that counsel for 
the Indemnifying Party, who shall conduct the defense of such claim or 
litigation, shall be approved by the Indemnified Party (whose approval shall 
not be unreasonably withheld), and the Indemnified Party may participate in 
such defense at such party's expense; and provided further, that the failure of 
any Indemnified Party to give notice as provided herein shall not relieve the 
Indemnifying Party of its obligations hereunder, unless such failure resulted 
in prejudice to the Indemnifying Party; and provided further, than an 
Indemnified Party (together with all other Indemnified Parties which may be 
represented without conflict by one counsel) shall have the right to retain one 
separate counsel, with the fees and expenses to be paid by the Indemnifying 
Party, if representation of such Indemnified Party by the counsel retained by 
the Indemnifying Party would be inappropriate due to actual or potential 
differing interests between such Indemnified Party and any other party 
represented by such counsel in such proceeding. No Indemnifying Party, in the 
defense of any such claim or litigation, shall, except with the consent of each 
Indemnified Party, consent to entry of any judgment or enter into any 
settlement which does not include as an unconditional term thereof the giving 
by the claimant or plaintiff to such Indemnified Party of a release from all 
liability in respect to such claim or litigation.

        1.6  Information by Holder. Any Holder or Holders of Registrable 
Securities included in any registration shall promptly furnish to the Company 
such information regarding such Holder or Holders and the distribution proposed 
by such Holder or Holders as the Company may request in writing and as shall be 
required in connection with any registration, qualification or compliance 
referred to herein.

        1.7  Rule 144 Reporting. With a view to making available to Holders the 
benefits of certain rules and regulations of the SEC which may permit the sale 
of the Registrable Securities to the public without registration, the Company 
agrees at all times to:

                (a) make and keep public information available, as those terms 
are understood and defined in SEC Rule 144, after 90 days after the effective 
date of the first registration filed by the Company for an offering of its 
securities to the general public;

                (b) file with the SEC in a timely manner all reports and other 
documents required of the Company under the Securities Act and the Exchange Act 
(at any time after it has become subject to such reporting requirements); and

                (c) so long as a Holder owns any Registrable Securities, to 
furnish to such Holder forthwith upon request a written statement by the 
Company as to its compliance with the reporting requirements of said Rule 144 
(at any time after 90 days after the effective date of the first registration 
statement filed by the Company for an offering of its securities to the general 
public) and 

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of the Securities Act and the Exchange Act (at any time after it has become 
subject to such reporting requirements), a copy of the most recent annual or 
quarterly report of the Company, and such other reports and documents so filed 
by the Company as the Holder may reasonably request in complying with any rule 
or regulation of the SEC allowing the Holder to sell any such securities 
without registration.

        1.8     Transfer of Registration Rights.  Holders' rights to cause the 
Company to register their securities and keep information available, granted to 
them by the Company under subsections 1.2 and 1.7 may be assigned to a 
transferee or assignee of a Holder's Registrable Securities not sold to the 
public, provided, that the Company is given written notice by such Holder at 
the time of or within a reasonable time after said transfer, stating the name 
and address of said transferee or assignee and identifying the securities with 
respect to which such registration rights are being assigned. The Company may 
prohibit the transfer of any Holders' rights under this subsection 1.8 to any 
proposed transferee or assignee who the Company reasonably believes is a 
competitor of the Company.

   2.   General.

        2.1     Waivers and Amendments.  With the written consent of the record 
or beneficial holders of at least a majority of the Registrable Securities, the 
obligations of the Company and the rights of the Holders of the Registrable 
Securities under this agreement may be waived (either generally or in a 
particular instance, either retroactively or prospectively, and either for a 
specified period of time or indefinitely), and with the same consent the 
Company, when authorized by resolution of its Board of Directors, may enter 
into a supplementary agreement for the purpose of adding any provisions to or 
changing in any manner or eliminating any of the provisions of this Agreement; 
provided, however, that no such modification, amendment or waiver shall reduce 
the aforesaid percentage of Registrable Securities without the consent of all 
of the Holders of the Registrable Securities. Upon the effectuation of each 
such waiver, consent, agreement of amendment or modification, the Company shall 
promptly give written notice thereof to the record holders of the Registrable 
Securities who have not previously consented thereto in writing. This Agreement 
or any provision hereof may be changed, waived, discharged or terminated only 
by a statement in writing signed by the party against which enforcement of the 
change, waiver, discharge or termination is sought, except to the extent 
provided in this subsection 2.1.

        2.2     Governing Law.  This Agreement shall be governed in all 
respects by the laws of the State of California as such laws are applied to 
agreements between California residents entered into and to be performed 
entirely within California.

        2.3     Successors and Assigns.  Except as otherwise expressly provided 
herein, the provisions hereof shall inure to the benefit of, and be binding 
upon, the successors, assigns, heirs, executors and administrators of the 
parties hereto.

        2.4     Entire Agreement.  Except as set forth below, this Agreement 
and the other documents delivered pursuant hereto constitute the full and 
entire understanding and agreement between the parties with regard to the 
subjects hereof and thereof.

        2.5     Notices, etc.  All notices and other communications required or 
permitted hereunder shall be in writing and shall be mailed by first class 
mail, postage prepaid, certified or registered mail, return receipt requested, 
addressed (a) if to Holder, at such Holder's address as set forth below, or at 
such other address as such Holder shall have furnished to the Company in 
writing, or (b) if to the Company, at the Company's address set forth below, or 
at such other address as the Company shall have furnished to the Holder in 
writing.

        2.6     Severability.  In case any provision of this Agreement shall be 
invalid, illegal, or unenforceable, the validity, legality and enforceability 
of the remaining provisions of this 

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Agreement or any provision of the other Agreements shall not in any way be 
affected or impaired thereby.

        2.7     Titles and Subtitles.  The titles of the sections and 
subsections of this Agreement are for convenience of reference only and are not 
to be considered in construing this Agreement.

        2.8     Counterparts.  This Agreement may be executed in any number of 
counterparts, each of which shall be an original, but all of which together 
shall constitute one instrument.



                                     
PURCHASER                               COMPANY

VENTURE LENDING, a Division of
CUPERTINO NATIONAL BANK & TRUST         ADVANCED POLYMER SYSTEMS, INC.

By: _______________________________     By: _______________________________

Name: _____________________________     Name: _____________________________
              (Print)                                 (Print)

Title: ____________________________     Title:  Chairman of the Board, 
                                                President or Vice President

Address: __________________________     Address: __________________________
         __________________________              __________________________
         __________________________              __________________________



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