1
      Portions of this Exhibit 10.33 have been redacted and are the subject of a
confidential treatment request filed with the Secretary of the Securities and
Exchange Commission.
   2
                                  EXHIBIT A TO
                             SUBSCRIPTION AGREEMENT

                         LICENSE AND SERVICES AGREEMENT


         This LICENSE AND SERVICES AGREEMENT, made the 17th day of July, 1997,
by and between Oncogene Science, Inc. ("OSI"), a Delaware corporation having its
principal place of business at 106 Charles Lindbergh Boulevard, Uniondale, New
York 11553, and Helicon Therapeutics, Inc. ("Company"), a Delaware corporation,
having its principal place of business at 106 Charles Lindbergh Boulevard,
Uniondale, New York 11553.


         WHEREAS, the Company was organized to discover, develop and market
pharmaceutical products; and

         WHEREAS, OSI is engaged in research relating to molecular screening and
modulation transcription; and

         WHEREAS, the Company wishes to obtain the use of certain proprietary
technology controlled by OSI for identifying the effect of compounds on genes
and gene expression which is useful in the process of developing products for
the treatment and prevention of human disease; and

         WHEREAS, the Company wishes to obtain the services of OSI in molecular
screening;


         NOW, THEREFORE, in consideration of the agreements and covenants herein
and for other valuable consideration, receipt of which is hereby acknowledged,
it is mutually agreed and covenanted by and among the parties to this Agreement
that:


1.       Licenses.

         a.       OSI hereby grants to the Company a world-wide, ** ,
                  non-exclusive license for a period of ten years, beginning as
                  of the date of the issuance of Preferred Stock, $.01 par value
                  per share, of the Company ("Preferred Stock") to OSI pursuant
                  to paragraph 6 of this Agreement, in the Field ("long term
                  memory and modulation of CREB** activity in synaptic
                  plasticity"), to use the technology and to commercialize the
                  products which are the subject of patent 

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**    This portion has been redacted pursuant to a confidential treatment
      request.
   3
                  applications with numbers as set forth in Exhibit 1 hereto
                  ("Applications") [and certain other technology, all] covering
                  a method of screening and modulation transcription. However,
                  if any patent or patents ("Patents") are issued as the result
                  of the Applications, the rights granted under this paragraph
                  1(a) will terminate as to the territory within the scope of
                  the Patents and the provisions of paragraph 1(b) below shall
                  apply.

         b.       OSI hereby grants to the Company a ** , non-exclusive license,
                  for a period beginning on the date of the first issuance of
                  the Patents and terminating on the date of the last expiration
                  of the Patents, in the Field, to use and commercialize the
                  "Patent Rights," which are (i) all Patents issued from the
                  Applications or from divisionals or continuations of the
                  Applications, (ii) all claims of United States and foreign
                  continuation-in-part applications and patents which are
                  directed to subject matter specifically described in the
                  Applications, (iii) all claims of all foreign patent
                  applications and patents which are directed to subject matter
                  specifically described in the United States patents and/or
                  patent applications described in (i) or (ii), and (iv) any
                  reissues or reexaminations or United States patents described
                  in (i), (ii) or (iii).

         c.       The licenses granted in paragraphs 1(a) and 1(b) may by mutual
                  agreement be extended on a case by case basis.

2.       The Company recognizes that the Applications contain highly valuable
         proprietary, confidential information ("Confidential Information") and
         agrees that, until the Applications have been finally processed by the
         applicable governmental entity, it will (i) keep confidential, and
         cause its employees to keep confidential, all Confidential Information,
         and (ii) not use Confidential Information except as expressly permitted
         in this Agreement. The Company also agrees that disclosure of the
         Confidential Information to any officer, employee, agent or consultant
         shall be made only if and to the extent necessary to carry out the
         Company's responsibilities under, first, the Collaborative Research and
         License Agreement ("Collaboration Agreement") by and between
         Hoffmann-La Roche Inc. and the Company, to be entered, and, second, the
         Funded Research and License Agreement ("Research Agreement") by and
         between CSHL and the Company, heretofore or hereafter entered, and
         shall be limited to the maximum extent possible consistent with such
         responsibilities. The Company agrees not to disclose Confidential
         Information to any third party under any circumstance without written
         permission. The Company shall take such action to preserve the
         confidentiality of the Confidential Information as it would customarily
         take to preserve the confidentiality of its own confidential
         information. The Company represents that all of its employees which
         shall have access to the Confidential Information are bound by
         agreement to maintain such information in confidence. Confidential
         Information will be so designated by OSI in writing at the time of
         disclosure 

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**    This portion has been redacted pursuant to a confidential treatment
      request.


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      to the Company, and will include that information which as of the date of
      disclosure to the Company is not (a) known to the Company other than by
      virtue of a prior confidential disclosure to the Company by OSI, or (b)
      disclosed in the published literature, or otherwise generally known to the
      public, or (c) obtained from a third party that has no obligation of
      confidentiality to OSI.

3.    OSI represents and warrants to the Company that (a) it is the holder of
      the Applications, (b) it has the right to grant the licenses granted in
      this Agreement, (c) there are no claims made against the Applications, and
      that (d) the licenses granted do not conflict with or violate the terms of
      any agreement between CSHL and any third party.

4.     Protection of Rights.

      a.    Each party shall promptly notify the other party in writing of
            any alleged or threatened infringement of the Patents of which it
            becomes aware.  OSI shall have the right but not the obligation
            to bring, at its own expense and in its sole control, an
            appropriate action against any person or entity infringing the
            Patents.  The Company shall be entitled to separate
            representation in the matter by counsel of its own choice and at
            its own expense, and shall fully cooperate with OSI in
            prosecuting the action.

      b.    If OSI or the Company is sued by a third party for infringement
            of a patent because of the Company's exercise of the rights
            granted in this Agreement, the party which has been sued shall
            promptly notify the other party in writing of the institution of
            the suit.  The Company shall give to OSI all authority (including
            the right to exclusive control of the defense of any such suit,
            action, or proceeding and the exclusive right to compromise,
            litigate, settle or otherwise dispose of any such suit, action or
            proceeding), information and assistance necessary to defend or
            settle any such suit, action or proceeding.  OSI shall bear the
            expenses for defending against any alleged infringement due to
            the exercise of the rights granted in this Agreement.  OSI agrees
            to defend, protect, indemnify and hold harmless the Company from
            and against any loss or expense arising from any claim of a third
            party that it has been granted rights by OSI and that the Company
            in exercising its rights granted to it by OSI pursuant to this
            Agreement, has infringed upon the rights granted to such third
            party by OSI.

5.    OSI will provide, during a one year period beginning as of the date of the
      issuance of the Preferred Stock by the Company to OSI pursuant to
      paragraph 6 of this Agreement, ** . OSI's collaborative rate is based
      upon**, allocated in the same manner as OSI does in its other
      collaborative research programs; an

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**    This portion has been redacted pursuant to a confidential treatment
      request.


                                      -3-
   5
         example of OSI's collaborative rate calculations is set forth in the
         initial budget for the Company. Initially, the collaborative rate for
         the Services is as set forth in Schedule A to this Agreement. The
         Services will be provided according to a Work Plan which will be
         established by the parties on a quarterly basis. For the first three
         month period, beginning as of the date of the issuance of the Preferred
         Stock by the Company to OSI pursuant to paragraph 6 of this Agreement,
         the Work Plan is set forth in Schedule B to this Agreement.

6.       In consideration for the rights granted herein, the Company will issue
         to OSI ** shares of its Preferred Stock within two days of the date of
         this Agreement as more fully set forth in the Subscription Agreement.

7.       Should ownership or control of the Company change due to a transaction
         or related series of transactions which result in more than fifty
         percent of the Company's voting stock being transferred to a single
         entity or related group of entities within a six month period, or in
         the sale of all or substantially all of the assets of its business, the
         Company shall inform OSI in writing of the relevant event within thirty
         days of its occurrence. If the acquiring entity does not agree in
         writing to assume and be bound by the obligations of this Agreement by
         providing written notice thereof to OSI within thirty days of the date
         the written notice of the occurrence of the event is provided to OSI,
         OSI may, at any subsequent time but not later than ninety days
         following receipt of notice of occurrence of the event, terminate the
         licenses and the Services provided pursuant to this Agreement upon
         giving three months prior written notice.

8.       OSI may terminate the licenses and the Services provided pursuant to
         this Agreement upon thirty days written notice if, at any time, the
         Company files a petition in bankruptcy or insolvency before the courts
         or applies for the appointment of a receiver or trustee for all of its
         assets or any part thereof, or if the Company proposes a written
         agreement of consolidation or extension of debts, or if the Company is
         served with an involuntary petition against it, filed in any insolvency
         proceeding, and such petition is not dismissed within sixty days after
         its filing, or if the Company proposes or is a party to any dissolution
         or liquidation, or if the Company makes an assignment for the benefit
         of creditors.

9.       The parties each represents and warrants that:

         a.       It is an entity duly organized, validly existing and is in
                  good standing under the laws of its domicile, is qualified to
                  do business and is in good standing as a corporation in each
                  jurisdiction in which the conduct of its business or the
                  ownership of its properties requires such qualification and
                  has all requisite power and authority to conduct its business
                  as now being conducted, to own, lease and operate its
                  properties and to execute, deliver and perform this Agreement.

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**    This portion has been redacted pursuant to a confidential treatment
      request.


                                      -4-
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      b.    The execution, delivery and performance by it of this Agreement
            have been duly authorized by all necessary action and do not and
            will not (i) require any consent or approval of its stockholders
            (other than that which has been obtained), (ii) violate any
            provision of any law, rule, regulation, writ, judgment,
            injunction, decree, determination or award presently in effect
            having applicability to it or any provision of its charter,
            organization agreement or by-laws or (iii) result in a breach of
            or constitute a default under any material agreement, mortgage,
            lease, license, permit or other instrument or obligation to which
            it is a party or by which it or its properties may be bound or
            affected.

      c.    This Agreement is a legal, valid and binding obligation of it
            enforceable against it in accordance with its terms and conditions,
            except as such enforceability may be limited by applicable
            bankruptcy, insolvency, moratorium, reorganization or similar laws,
            from time to time in effect, affecting creditor's rights generally.

10.   All notices shall be mailed via certified mail, return receipt requested,
      or courier addressed as follows, or to such other address as may be
      designated from time to time:


             If to OSI:                At its address as set forth at the
                                       beginning of this Agreement

                                       Attn.: Arthur Bruskin, Ph.D.
                                              Oncogene Science, Inc.
                                              106 Charles Lindbergh Boulevard
                                              Uniondale, NY 11553

             If to the Company:        At its address as set forth at the
                                       beginning of this Agreement

                                       Attn.: Walter Lovenberg, Ph.D.
                                              Helicon Therapeutics, Inc.
                                              106 Charles Lindbergh Boulevard
                                              Uniondale, NY 11553



      Notices shall be deemed given as of the date of receipt.

11.   This Agreement shall be construed in accordance with the laws of the
      State of New York.

12.   This Agreement shall be binding upon and inure to the benefit of the
      parties and their respective legal representatives, successors and
      permitted assigns.  This Agreement may not be assigned by either party,
      except that the parties may assign this Agreement and their rights and
      interest, in whole or in part, to any of their affiliates, any
      purchaser of all 


                                      -5-
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      or substantially all of its assets or to any successor corporation
      resulting from any merger or consolidation with or into such corporation.

13.   This Agreement may be amended, modified, superseded or canceled, and any
      of its terms may be waived, only by a written instrument executed by each
      party or, in the case of waiver, by the party or parties waiving
      compliance. The delay or failure of any party at any time or times to
      require performance of any provision shall in no manner affect the rights
      at a later time to enforce the same.

14.   No person not a party to this Agreement shall have or acquire any rights
      by reason of this Agreement. Nothing contained in this Agreement shall be
      deemed to constitute the parties partners with each other or any other
      person or entity.


      IN WITNESS WHEREOF, the parties have caused this Agreement to be executed
by their duly authorized representatives.


                                        Oncogene Science, Inc.


                                        By:__________________________________

                                        Title:_______________________________


                                        Helicon Therapeutics, Inc.


                                        By:__________________________________

                                        Title:_______________________________


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