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                                 April 24, 1995



                                                                      10008-0029



Advanced Polymer Systems, Inc.
3696 Haven Avenue
Redwood City, California 94063

                       Registration Statement on Form S-3
                       ----------------------------------

Ladies and Gentlemen:

         We have acted as counsel to Advanced Polymer Systems, Inc., a Delaware
corporation (the "Company"), in connection with the Registration Statement on
Form S-3 (No. 33-88972) (the "Registration Statement") which the Company filed
with the Securities and Exchange Commission on January 31, 1995, and an
amendment thereto filed herewith, for the purpose of registering under the
Securities Act of 1933, as amended, an aggregate of 1,284,112 Shares of its
Common Stock, $.01 par value (the "Shares"), 642,056 of which are currently
issued and outstanding and are to be sold by certain of the Company's
stockholders and 642,056 of which are issuable upon exercise of currently
outstanding warrants to purchase Company Common Stock (the "Warrants").  Of the
issued and outstanding Shares, 321,028 were issued to GDK, Inc. (the "GDK
Shares") pursuant to the Unit Purchase Agreement dated June 6, 1994 (the "Unit
Purchase Agreement") and 321,028 were issued to Ortelius L. P. (the "Ortelius
Shares") pursuant to the Unit Purchase Agreement.  Of the Shares issuable upon
exercise of Warrants, 321,028 (the "Ortelius Warrant Shares") are issuable upon
upon exercise of two warrants by Ortelius L. P. (the "Ortelius Warrant"); and
321,028 (the "GDK Warrant Shares") are issuable upon exercise of two warrants
issued to GDK, Inc. (the "GDK Warrant").

         In connection with this opinion, we have assumed the authenticity of
all records, documents and instruments submitted to us as originals, the
genuineness of all signatures, the legal capacity of natural persons and the
conformity to the originals of all records, documents and instruments submitted
to us as

                                   EXHIBIT 5

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April 24, 1995
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copies.  We have based our opinion upon our review of the following records,
documents, instruments and certificates:

           (a)  The Certificate of Incorporation of the Company certified by the
                Secretary of State of the State of Delaware as of March 27,
                1995, and certified to us by an officer of the Company as being
                complete and in full force and effect as of the date of this
                opinion;

           (b)  The Bylaws of the Company certified to us by an officer of the
                Company as being complete and in full force and effect as of the
                date of this opinion;

           (c)  Records certified to us by an officer of the Company as
                constituting all records of proceedings and actions of the Board
                of Directors of the Company relating to the Shares;

           (d)  A certificate of the Chief Financial Officer of the Company as
                to certain factual matters;

           (e)  The Registration Statement;

           (f)  The Unit Purchase Agreement;

           (g)  The Ortelius Warrant;

           (h)  The GDK Warrant; and

           (i)  A letter from First National Bank of Boston, the Company's
                transfer agent, dated March 29, 1995, as to the number of
                Company's Common Stock that were outstanding on March 29, 1995.

         This opinion is limited to the Delaware General Corporation Law.  We
disclaim any opinion as to any other statute, rule, regulation, ordinance, order
or other promulgation of any other jurisdiction or any regional or local
governmental body.

         Our opinion expressed herein assumes that the Unit Purchase Agreement
has been duly authorized, executed and delivered by the parties thereto in the
form that we have reviewed as of the date of this opinion, and that the full
purchase price stated in the Unit Purchase Agreement and the


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April 24, 1995
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Board of Directors minutes authorizing the Unit Purchase Agreement is paid.

         Based upon the foregoing and our examination of such questions of law
as we have deemed necessary or appropriate for the purpose of this opinion, and
assuming that:  (i)  the Registration Statement becomes and remains effective
during the period when the Shares are offered, issued and sold; (ii) all
applicable securities laws are complied with; and (iii) the Shares issuable on
exercise of the Ortelius Warrant and the GDK Warrant are issued in accordance
with the terms of each such warrant, it is our opinion that:

         1.  The Ortelius Shares were validly issued, fully paid and
non-assessable.

         2.  The GDK Shares were validly issued, fully paid and non-assessable.

         3.  The Ortelius Warrant Shares, when issued in accordance with the
terms of Ortelius Warrant, will be validly issued, fully paid and
non-assessable.

         4.  The GDK Warrant Shares, when issued in accordance with the terms of
the GDK Warrant, will be validly issued, fully paid and non-assessable.

         This opinion is rendered to you in connection with the Registration
Statement and is solely for your benefit.  This opinion may not be relied upon
by you for any other purpose, or relied upon by any other person, firm,
corporation or other entity for any purpose, without our prior written consent.
We disclaim any obligation to advise you of any developments that occur after
the date of this opinion.

         We hereby consent to the filing of this opinion as an exhibit to the
Registration Statement.

                                   Very truly yours,



                                   /s/  Heller, Ehrman, White & McAuliffe
                                   -------------------------------------
                                   Heller, Ehrman, White & McAuliffe