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                                                                   EXHIBIT 10.45


                          STOCK SUBSCRIPTION AGREEMENT


       THIS STOCK SUBSCRIPTION AGREEMENT ("Agreement") is made and entered into
as of this 20th day of November, 1996, by and among Ribozyme Pharmaceuticals,
Inc., a Delaware corporation (the "Company"), and United States Biochemical
Corporation, an Ohio corporation (the "Purchaser").

                                    RECITALS

       A.     The Company is a publicly-held company engaged in the business of
developing and commercializing its ribozyme technology.

       B.     The Company and the Purchaser have entered into that certain
Sublicense Agreement and that certain Assignment of License and Restated
License Agreement, both of  even date herewith, granting certain rights to the
Company with respect to certain Licensed Patents identified therein (the
"Licenses").

       C.     As consideration for such Licenses, the Purchaser desires to
acquire and the Company has agreed to issue to the Purchaser an additional
equity investment in the Company on the terms and conditions set forth in this
Agreement.

       IN CONSIDERATION OF the mutual promises, representations, warranties and
covenants contained herein, the parties hereto agree as follows:




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                    ARTICLE  I.  PURCHASE AND SALE OF SHARES

       Subject to the terms and conditions set forth in this Agreement, the
Purchaser hereby purchases and the Company hereby sells 22,500 shares
("Shares") of the Company's Common Stock ($.01 par value) ("Common Stock"), in
consideration for the rights granted to the Company under the Licenses, the
receipt and sufficiency of which is hereby acknowledged by the Company.  The
certificate or certificates representing such Shares will be issued by the
Company in the name of Amersham Holdings, Inc., as nominee for the Purchaser.

                        ARTICLE II.  REGISTRATION RIGHTS

       2.1    At any time on or after April 11, 1997 Purchaser may make written
request to the Company to register the Shares under the Securities Act of 1933
(the "Act") and any applicable state securities laws (or to qualify or exempt
the Shares thereunder).  As soon as reasonably practicable following the
receipt of such request, the Company will use its commercially reasonable best
efforts to (i) file with the Securities and Exchange Commission (the
"Commission") a Registration Statement on Form S-3 (or any alternative or
successor form adopted by the Commission that is appropriate therefor)
registering the Shares under the Act and Rule 415 (or any successor Rule
adopted by the Commission) thereunder, (ii) cause such Registration Statement
to be declared effective as soon thereafter as is practicable and (iii) cause
such Registration Statement to remain effective for a period of not less than
120 days thereafter.  Each such request shall be made by delivery of written
notice to the Company by Purchaser, which notice shall (i) request the
preparation of the Registration Statement pursuant to the terms of this Section
2.1, (ii) include the number of shares of Common Stock to be offered by
Purchaser pursuant to such Registration Statement, and (iii) be sent by the
Company to any other Shareholders as provided in Section 2.2 below.

       2.2    Within 30 calendar days after receipt of notice of any
registration requested hereunder, the Company shall have the right to send a
copy of such notice to any other shareholder that the Company, in its sole
discretion, deems appropriate (collectively,





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"Shareholders"), which notice shall be accompanied by an offer by the Company
to include all or part of the Common Stock held by such Shareholder in such
registration.

       2.3    In the event that the Company is or becomes obligated to file a
Registration Statement for any other reason other than this Article II on or
after April 11, 1997, the Company shall give Purchaser notice of such pending
registration accompanied by an offer by the Company  to include the Shares in
such Registration Statement.

       2.4    Notwithstanding anything contained herein to the contrary, the
Company will not be obligated to effect, or take any further action to effect,
any registration pursuant to this Article II after the Company has effected two
(2) registrations on Form S-3 (or any alternative or successor form adopted by
the Commission that is appropriate for the registration for the Shares) on or
after April 11, 1997, which Registration Statements have been declared or
ordered effective.  Purchaser shall not initiate any request for registration
pursuant to Section 2.1 during such time as the Company is using its
commercially reasonable best efforts to cause any Registration Statement
referenced in Section 2.3 to be declared or ordered effective.

                 ARTICLE  III.  REPRESENTATIONS OF THE COMPANY

              The following are representations and warranties made by the
Company as of the date hereof.

       3.1    ORGANIZATION AND STANDING.  The Company is a corporation duly
organized, validly existing and in good standing under the laws of the State of
Delaware and has full corporate power and authority to conduct its business as
presently conducted and as proposed to be conducted by it and to enter into and
perform this Agreement and to carry out the transactions contemplated herein.
The Company is duly qualified to do business as a foreign corporation and is in
good standing under the laws of the State of Colorado and under the laws of any
other state in which qualification by the Company to do business is required.
The Company has furnished to the Purchaser true and complete copies of its
Amended and Restated Certificate of





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Incorporation (the "Certificate of Incorporation") and By-Laws, each as amended
to date and as currently in effect.

       3.2    CAPITALIZATION.  The authorized capital stock of the Company
consists of: (i) 20,000,000 shares of Common Stock, of which 6,856,054 are
issued and outstanding, 348,057 are issuable upon exercise of certain stock
options granted under the Stock Option Plans of the Company, and 487,458 are
reserved for issuance upon exercise of warrants issued by the Company; and (ii)
5,000,000 shares of Preferred Stock, $.01 par value per share, none of which
are issued or outstanding.  The issued and outstanding shares of Common Stock
are duly and validly issued, fully-paid and non-assessable.  Except as set
forth above, (i) no subscription, warrant, option, convertible security or
other right (contingent or otherwise) to purchase or acquire any shares of
capital stock of the Company is authorized or outstanding, and (ii) there is
not any commitment of the Company to issue any subscription, warrant, option,
convertible security or other such right or to issue or distribute to holders
of any shares of its capital stock any evidences of indebtedness or assets of
the Company.

       3.3    ISSUANCE OF SHARES.  The issuance, sale and delivery of the
Shares in accordance with this Agreement has been duly authorized by all
necessary corporate action on the part of the Company, and the Shares when so
issued, sold and delivered against payment therefor in accordance with the
provisions of this Agreement will be duly and validly issued, fully paid and
nonassessable.

       3.4    AUTHORITY FOR AGREEMENT.  The execution, delivery and performance
by the Company of this Agreement have been duly authorized by all necessary
corporate action, including actions of the Board of Directors of the Company,
and this Agreement has been duly executed and delivered by the Company.  This
Agreement constitutes a valid and binding obligation of the Company enforceable
in accordance with its terms, subject as to enforcement of remedies to
applicable bankruptcy, insolvency, reorganization or similar laws affecting
generally the enforcement of creditors' rights and subject to a court's
discretionary authority with respect to the granting of a decree ordering
specific performance or other equitable remedies.  The execution of, and the
Company's performance of the transactions contemplated by, this Agreement and
compliance with its provisions 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





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of, or constitute a default under, its Certificate of Incorporation or By-Laws
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, or any decree,
judgment, order, statute, rule or regulation applicable to the Company and will
not constitute an event which with the lapse of time or notice by a third party
could result in any default under any of the foregoing or result in the
creation of any lien, charge or encumbrance upon the assets or properties of
the Company or upon its stock.

       3.5    GOVERNMENTAL CONSENTS.  No consent, approval, order or
authorization of, or registration, qualification, designation, declaration or
filing with, any governmental authority is required on the part of the Company
in connection with the execution and delivery of this Agreement or the offer,
issue, sale and delivery of the Shares.

       3.6    DISCLOSURES.  As of the date of this Agreement, neither this
Agreement nor any exhibit hereto, nor any report, other written statement or
certificate delivered or to be furnished to Purchaser in connection with the
transactions contemplated by this Agreement, when read together, contains or
will contain any material misstatement of fact or omits or will omit to state a
material fact necessary to make the statements contained herein or therein not
misleading.

                 ARTICLE IV.  REPRESENTATIONS OF THE PURCHASER

       Purchaser represents and warrants to the Company as follows:

       Section 4.1   INVESTMENT.  Purchaser is acquiring the Shares, for its
own account, for investment and not with a view to, or for sale in connection
with, any public distribution thereof and, except as contemplated by this
Agreement, Purchaser has no present or contemplated agreement, undertaking,
arrangement, obligation, indebtedness or commitment providing for the
disposition thereof.

       Section 4.2   AUTHORITY.  Purchaser has full power and authority to
enter into and to perform this Agreement in accordance with its terms.
Purchaser has not been organized, reorganized or recapitalized specifically for
the purpose of investing in the Company.

       Section 4.3   EXPERIENCE.  Purchaser has made detailed inquiry
concerning the Company, its business and its personnel; Purchaser has received
any and all written information which it has requested and all questions and
inquiries have been answered to Purchaser's





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satisfaction; and Purchaser has sufficient business and financial experience to
be able to evaluate the merits and risks of an investment in the Company.

       Section 4.4   ACCREDITED INVESTOR.  Purchaser is an "accredited
investor" within the definition set forth in Rule 501(a) under the Securities
Act.

       Section 4.5   BINDING EFFECT.  This Agreement has been duly executed and
delivered by Purchaser, constitutes a valid and binding obligation of
Purchaser, and is enforceable in accordance with its terms, subject as to
enforcement of remedies to applicable bankruptcy, insolvency, reorganization or
similar laws affecting generally the enforcement of creditors' rights and
subject to a court's discretionary authority with respect to the granting of a
decree ordering specific performance or other equitable remedies.

       Section 4.6   RESTRICTED SECURITIES.  Purchaser acknowledges that (i)
the Shares have not been registered under the Securities Act and are
"restricted securities" within the meaning of Rule 144 under the Securities
Act; and (ii) the Shares cannot be sold, transferred or otherwise disposed of
unless they are subsequently registered under the Securities Act or an
exemption from registration is then available.  The certificates representing
the shares may contain a legend noting these restrictions.

       Section 4.7   PURCHASER AGREEMENTS.  There are no agreements, written or
oral, to which Purchaser is a party relating to the acquisition, disposition or
voting of the capital stock of the Company.  In the event any such agreement is
entered into by the Purchaser, Purchaser shall be obligated to deliver a copy
thereof to the Company or notify the Company of any such oral agreement.

                           ARTICLE V.  MISCELLANEOUS

       Section 5.1   SURVIVAL OF REPRESENTATIONS, WARRANTIES AND COVENANTS.
All agreements, representations, warranties and covenants contained herein
shall survive the execution and delivery of this Agreement and the closing of
the transactions contemplated hereby.

       Section 5.2   EXPENSES.  Each party shall pay its own expenses in
connection with the investment contemplated herein.





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       Section 5.3   NOTICES.  All notices, requests, consents, and other
communications when deemed given under this Agreement shall be in writing and
shall be delivered by hand, which shall include delivery by express courier
service, or mailed by first class certified or registered mail, return receipt
requested, postage prepaid and notice shall be deemed given when actually
received by the intended recipient:

       If to the Company:

              Ribozyme Pharmaceuticals, Inc.
              2950 Wilderness Place
              Boulder, CO  80301

              Attention:  President

       With a copy to:

              Herbert H. Davis III
              Rothgerber, Appel, Powers & Johnson LLP
              1200 17th Street, Suite 3000
              Denver, CO  80202-5839

       If to Purchaser:

              United States Biochemical Corporation
              26111 Miles Road
              Cleveland, OH 44128

              Attention: President

or at such other address or addresses as may have been furnished in writing
pursuant to the provision of this Section 4.3.

       Section 5.4   BROKERS.  The Company and Purchaser (i) represent and
warrant to the other that it has retained no finder or broker in connection
with the transactions contemplated by this Agreement, and (ii) will indemnify
and save the other party harmless from and against any and all claims,
liabilities or obligations with respect to brokerage or finders' fees or
commissions or consulting fees in connection with the transactions contemplated
by this Agreement asserted by any person on the basis of any statement or
representation alleged to have been made by such indemnifying party.





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       Section 5.5   ENTIRE AGREEMENT.  This Agreement together with the other
agreements referred to herein embody the entire agreement and understanding
between the parties hereto with respect to the subject matter hereof and
supersedes all prior agreements and understandings relating to such subject
matter.

       Section 5.6   AMENDMENTS AND WAIVERS.  Except as otherwise expressly set
forth in this Agreement, any term of this Agreement may be amended and the
observance of any term of this Agreement may be waived (either generally or in
a particular instance and either retroactively or prospectively), with the
written consent of the Company as to any provision that is for the benefit of
the Company and by the Purchaser.

       Section 5.7   COUNTERPARTS.  This Agreement may be executed in several
counterparts, each of which shall be deemed an original, but all of which
together shall constitute one and the same instrument.

       Section 5.8   HEADINGS.  The headings of the sections, Articles, and
paragraphs of this Agreement have been added for convenience only and shall not
be deemed to be a part of this Agreement.

       Section 5.9   SEVERABILITY.  The invalidity or unenforceability of any
provision of this Agreement shall not affect the validity or enforceability of
any other provision.

       Section 5.10  GOVERNING LAW.  This Agreement shall be governed by and
construed in accordance with the laws of the State of Delaware.

       Section 5.11  SUCCESSORS AND ASSIGNS.  The provisions of this Agreement
shall be binding upon, and inure to the benefit of, the respective successors,
assigns, heirs, executors and administrators of the parties hereto.





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       IN WITNESS WHEREOF, the undersigned have hereunto set their hands as of
the day and year first above written.



RIBOZYME PHARMACEUTICALS, INC.           UNITED STATES BIOCHEMICAL CORPORATION


By:    /s/ Ralph E. Christoffersen       By:     /s/ Tom Mann

Title: President/CEO                     Title:  President

Date:  November 20, 1996                 Date:   November 20, 1996





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