EXHIBIT 4

                                                                  Execution Copy

THIS WARRANT CERTIFICATE AND THE SECURITIES REPRESENTED BY THIS WARRANT
CERTIFICATE AND THE SHARES OF STOCK ISSUABLE UPON EXERCISE HEREOF HAVE BEEN
ACQUIRED FOR INVESTMENT AND HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF
1933, AS AMENDED, OR ANY SECURITIES LAWS OF A STATE OR OTHER JURISDICTION AND
MAY NOT UNDER ANY CIRCUMSTANCES BE SOLD, TRANSFERRED OR OTHERWISE DISPOSED OF
(OTHER THAN TO AN AFFILIATE OR AS OTHERWISE PERMITTED BY THIS WARRANT
CERTIFICATE PURSUANT TO WHICH THEY WERE ISSUED) EXCEPT PURSUANT TO (i) AN
EFFECTIVE REGISTRATION STATEMENT UNDER THE SECURITIES ACT AND ANY APPLICABLE
STATE SECURITIES OR BLUE SKYLAWS, OR (ii) TO THE EXTENT APPLICABLE, RULE 144
UNDER THE SECURITIES ACT (OR ANY SIMILAR RULE UNDER THE SECURITIES ACT RELATING
TO THE DISPOSITION OF SECURITIES) TOGETHER WITH AN OPINION OF COUNSEL
SATISFACTORY TO THE COMPANY THAT REGISTRATION IS NOT REQUIRED UNDER SUCH ACT OR
APPLICABLE STATE SECURITIES LAWS.

                        RIBOZYME PHARMACEUTICALS, INC.

                          WARRANT TO PURCHASE SHARES
                                OF COMMON STOCK

          THIS CERTIFIES THAT, for value received, Elan International Services,
Ltd., a Bermuda exempted limited liability company, or its permitted transferees
and successors as provided herein (each, a "Holder"), is entitled to subscribe
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for and purchase up to 200,000 shares, as adjusted pursuant to Section 4 (the
"Shares"), of the fully paid and nonassessable common stock, par value $.01 (the
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"Common Stock"), of Ribozyme Pharmaceuticals, Inc., a Delaware corporation (the
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"Company"), at the price of U.S.$15.00 per share (such price, and such other
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prices that shall result from time to time, from the adjustments specified in
Section 4, the "Warrant Price"), subject to the provisions and upon the terms
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and conditions hereinafter set forth.

          1. Term.  Subject to the limitations set forth in Sections 3 and 4,
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the purchase right represented by this Warrant is exercisable, in whole or in
part, at any time, and from time to time, from and after the date hereof and
until 5:00 p.m. Eastern Standard Time, January 7/th/, 2002.  To the extent not
exercised at 5:00 p.m. Eastern Standard Time on January 7/th/, 2002, this
Warrant shall terminate and expire, and thereafter it shall be of no force or
effect.


          2.  Method of Exercise; Payment; Issuance of New Warrant. (a) The
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purchase right represented by this Warrant may be exercised by the Holder, in
whole or in part and from time to time, by the surrender of this Warrant (with
the notice of exercise form attached hereto as Annex A duly executed) at the
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principal office of the Company and by the payment to the Company of an amount,
in cash or other immediately available funds, equal to the then-applicable
Warrant Price per Share multiplied by the number of Shares then being purchased.

          (b)  The persons or entities in whose name(s) any certificate(s)
representing Shares shall be issuable upon exercise of this Warrant shall be
deemed to have become the holder(s) of record of, and shall be treated for all
purposes as the record holder(s) of, the Shares represented thereby (and such
Shares shall be deemed to have been issued) immediately prior to the close of
business on the date or dates upon which this Warrant is properly exercised and
full payment for the Shares acquired pursuant to such exercise is made.  Upon
any exercise of the rights represented by this Warrant, certificates for the
Shares purchased shall be delivered to the holder hereof as soon as possible and
in any event within 30 days of receipt of such notice and payment, and unless
this Warrant has been fully exercised or expired, a new Warrant representing the
portion of Shares, if any, with respect to which this Warrant shall not then
have been exercised shall also be issued to the holder hereof as soon as
possible and in any event within such 30-day period.

          3.  Stock Fully Paid, Reservation of Shares.  All Shares that may be
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issued upon the exercise of this Warrant shall, upon issuance, be duly and
validly authorized and issued, fully paid and nonassessable, and will be free
from all transfer taxes, liens and charges with respect to the issue thereof and
assuming payment of the Warrant Price for all Shares so purchased, legally and
validly owned by the Holder.  During the period within which this Warrant may be
exercised, the Company will at all times have authorized, and reserved for the
purpose of the issue upon the exercise of the purchase rights evidenced by this
Warrant, a sufficient number of shares of its Common Stock to provide for the
exercise of the rights represented by this Warrant.

          4.  Adjustment of Warrant Price and Number of Shares.  The number and
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kind of securities purchasable upon the exercise of this Warrant and the Warrant
Price shall be subject to the adjustment from time to time upon the occurrence
of certain events, as follows:

          (a)  Reclassification, Etc.  In case of any reclassification,
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reorganization, change or conversion of securities of the class issuable upon
exercise of this Warrant (other than a change in par value, or from par value to
no par value) of other shares or securities of the Company, or (ii) any
consolidation of  the Company with or into another entity (other than a merger
or consolidation with another entity in which the Company is the acquiring and
the surviving entity and that does not result in any reclassification or change
of outstanding securities issuable upon exercise of this Warrant), or (iii) any
sale of all or substantially all the assets of the Company, then, in any such
event, (x) the Company, or such successor or purchasing entity, as the case may
be, shall duly execute and deliver to the holder of this Warrant a new Warrant
or a supplement hereto (in form and substance reasonably satisfactory to the
holder of this Warrant), and (y) the Holder shall have the right to receive, at
a total purchase price not to exceed that payable upon the exercise of the
unexercised portion of this Warrant, and in lieu of

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the shares of Common Stock theretofore issuable upon the exercise of this
Warrant, the kind and amount of shares of stock and other securities, receivable
upon such reclassification, reorganization, change or conversion by a holder of
the number of shares of Common Stock then purchasable under this Warrant. Such
new Warrant shall provide for adjustments that shall be as nearly equivalent as
may be practicable to the adjustments provided for in this Section 4. The
provisions of this Section 4(a) shall similarly attach to successive
reclassifications, reorganizations, changes, and conversions.

          (b)   Subdivision or Combination of Shares.  If the Company at any
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time during which this Warrant remains outstanding and unexpired shall subdivide
or combine its Common Stock, (i) in the case of a subdivision, the Warrant Price
shall be proportionately and appropriately decreased and the number of Shares
purchasable hereunder shall be proportionately and appropriately increased, and
(ii) in the case of a combination, the Warrant Price shall be proportionately
and appropriately increased and the number of Shares purchasable hereunder shall
be proportionately and appropriately decreased.

          (c)   No Impairment.  The Company will not, by amendment of its
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Articles of Incorporation or bylaws or through any reorganization,
recapitalization, 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
hereunder by the Company, but will at all times in good faith assist in the
carrying out of all the provisions of this Section 4 and in the taking of all
such action as may be necessary or appropriate in order to protect the rights of
the Holder against impairment.

          (d)   Notice of Adjustments.  Whenever the Warrant Price or the number
                ---------------------
of Shares purchasable hereunder shall be adjusted pursuant to this Section 4,
the Company shall prepare a certificate setting forth, in reasonable detail, the
event requiring the adjustment, the amount of the adjustment, the method by
which such adjustment was calculated.  Such certificate shall be signed by its
chief financial officer and shall be delivered to the Holder.

          (e)   Fractional Shares.  No fractional Shares will be issued in
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connection with any exercise hereunder, but in lieu of such fractional shares
the Company shall make a cash payment therefor based on the fair market value of
the Common Stock on the date of exercise as reasonably determined in good faith
by the Company's Board of Directors.

          (f)   Cumulative Adjustments. No adjustment in the Warrant Price shall
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be required under this Section 4 until cumulative adjustments result in a
concomitant change of 1% or more of the Warrant Price or in the number of shares
of Common Stock purchasable upon exercise of this Warrant as in effect prior to
the last such adjustment; provided, however, that any adjustment that by reason
of this Section 4 are not required to be made shall be carried forward and taken
into account in any subsequent adjustment.  All calculations under this Section
4 shall be made to the nearest cent or to the nearest one-hundredth of a share,
as the case may be.

          5.  Compliance with Securities Act; Disposition of Warrant or Shares
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of Common Stock.  (a)  The Holder, by acceptance hereof, agrees that this
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Warrant and the Shares to be

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issued upon exercise hereof are being acquired for investment and that such
holder will not offer, sell or otherwise dispose of this Warrant or any Shares
to be issued upon exercise hereof except under circumstances which will not
result in a violation of applicable securities laws. Upon exercise of this
Warrant, unless the Shares being acquired are registered under the Securities
Act of 1933, as amended (the "Act"), or an exemption from the registration
                              ---
requirements of such Act is available, the Holder shall confirm in writing, by
executing an instrument in form reasonably satisfactory to the Company, that the
Shares so purchased are being acquired for investment and not with a view toward
distribution or resale. This Warrant and all Shares issued upon exercise of this
Warrant (unless registered under the Act) shall be stamped or imprinted with a
legend in substantially the following form:

THIS WARRANT CERTIFICATE AND THE SECURITIES REPRESENTED BY THIS WARRANT
CERTIFICATE AND THE SHARES OF STOCK ISSUABLE UPON EXERCISE HEREOF HAVE BEEN
ACQUIRED FOR INVESTMENT AND HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF
1933, AS AMENDED, OR ANY SECURITIES LAWS OF A STATE OR OTHER JURISDICTION AND
MAY NOT UNDER ANY CIRCUMSTANCES BE SOLD, TRANSFERRED OR OTHERWISE DISPOSED OF
(OTHER THAN TO AN AFFILIATE OR AS OTHERWISE PERMITTED BY THIS WARRANT
CERTIFICATE PURSUANT TO WHICH THEY WERE ISSUED) EXCEPT PURSUANT TO (i) AN
EFFECTIVE REGISTRATION STATEMENT UNDER THE SECURITIES ACT AND ANY APPLICABLE
STATE SECURITIES OR BLUE SKYLAWS, OR (ii) TO THE EXTENT APPLICABLE, RULE 144
UNDER THE SECURITIES ACT (OR ANY SIMILAR RULE UNDER THE SECURITIES ACT RELATING
TO THE DISPOSITION OF SECURITIES) TOGETHER WITH AN OPINION OF COUNSEL
SATISFACTORY TO THE COMPANY THAT REGISTRATION IS NOT REQUIRED UNDER SUCH ACT OR
APPLICABLE STATE SECURITIES LAWS.

          (b)(i) This Warrant may be transferred or assigned, in whole or in
part, (a) by EIS to its affiliates and subsidiaries, as well as any special
purpose financing or similar vehicle established by EIS or its affiliates.
Other than as set forth above, this Warrant may not be transferred or assigned
by either party without the prior written consent of the other.  Subject to the
foregoing, this Warrant and all of the provisions hereof shall be binding upon
and inure to the benefit of the parties hereto and their respective successors
and permitted assigns; provided, however that the transferor and the Company
shall continue to be liable and obligated for their respective obligations
hereunder after any such assignment.

          (ii) With respect to any offer, sale or other disposition of this
Warrant or any Shares acquired pursuant to the exercise of this Warrant prior to
registration of such Shares, the Holder shall give written notice to the Company
prior thereto, describing briefly the manner thereof, together with a written
opinion of such holders counsel, if requested by the Company, to the effect that
such offer, sale or other disposition may be effected without registration or
qualification (under the Act as then in effect or any federal or state law then
in effect) of this Warrant or such Shares and indicating whether or not under
the Act certificates for this Warrant or such Shares to be sold or otherwise
disposed of require any restrictive legend as to applicable

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restrictions on transferability in order to ensure compliance with the Act.
Promptly upon receiving such written notice and reasonably satisfactory opinion,
if so requested, the Company, as promptly as practicable, shall notify such
Holder that such Holder may sell or otherwise dispose of this Warrant or such
Shares, all in accordance with the terms of the notice delivered to the Company.
Each certificate representing this Warrant or the Shares thus transferred shall
bear a legend as to the applicable restrictions on transferability in order to
insure compliance with the Securities Act, unless in the aforesaid opinion of
counsel for the Holder such legend is not required in order to insure compliance
with the Securities Act. The Company may issue stop transfer instructions to its
transfer agent in connection with such restrictions.

          (iii) The shares of Common Stock underlying this Warrant are entitled
to the benefit of certain registration rights as set forth in a Registration
Rights Agreement dated as of the date hereof between the Company and the initial
Holder named herein.

          6.  Rights as Shareholders.  No Holder, as such, shall be entitled to
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vote or receive dividends or be deemed the holder of Shares or any other
securities of the Company which may at any time be issuable on the exercise
hereof for any purpose, nor shall anything contained herein be construed to
confer upon the Holder, as such, any right to vote for the election of directors
or upon any matter submitted to shareholders at any meeting thereof, or to
receive notice of meetings, or to receive dividends or subscription rights or
otherwise until this Warrant is exercised and the Shares purchasable upon the
exercise hereof shall have become deliverable, as provided herein.

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

          (a)   The Company has all requisite corporate power and authority to
authorize and execute this Warrant and the certificates evidencing the Shares
and to perform all obligations and undertakings under this Warrant and the
certificates evidencing the Shares;

          (b)   This Warrant has been duly authorized and executed by the
Company and is a valid and binding obligation of the Company enforceable in
accordance with its terms;

          (c)   The Shares have been duly authorized and reserved for issuance
by the Company and, when issued in accordance with the terms hereof, will be
validly issued, fully paid and nonassessable; and

          (d)   The execution and delivery of this Warrant are not, and the
issuance of the Shares upon exercise of this Warrant in accordance with the
terms hereof will not be, inconsistent with the Company's Certificate of
Incorporation or bylaws, as amended, and do not and will not constitute a
default under, any indenture, mortgage, contract or other instrument of which
the Company is a party or by which it is bound.

          8.  Miscellaneous.  (a) This Warrant may not be modified or amended,
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or any provisions hereof waived, except by written agreement of the Company and
the Holder.

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          (b)  Any notice, request or other document required or permitted to be
given or delivered to the Holder or the Company shall (i) be in writing, (ii) be
delivered personally or sent by mail or overnight courier to the intended
recipient to Holder at its address as shown on the books of the Company or to
the Company at the address indicated therefor on the signature page of this
Warrant, unless the recipient has given notice of another address, and (iii) be
effective on receipt if delivered personally, two business days after dispatch
if mailed, and one business day after dispatch if sent by overnight courier
service.

          (c)  The Company covenants to the Holder that upon receipt of evidence
reasonably satisfactory to the Company of the loss, theft, destruction or
mutilation of this Warrant and, in the case of any such loss, theft or
destruction, upon receipt of a bond or indemnity reasonably satisfactory to the
Company, or in the case of any such mutilation upon surrender and cancellation
of such Warrant, the Company will make and deliver a new Warrant, of like tenor,
in lieu of the lost, stolen, destroyed or mutilated Warrant.

          (d)  The descriptive headings of the several sections and paragraphs
of this Warrant are inserted for convenience only and do not constitute a part
of this Warrant.

          (e)  This Warrant shall be governed by and construed in accordance
with the substantive (as opposed to procedural) laws of the State of Delaware,
without giving effect to the principles thereof relating to conflicts of laws.

          (f)  This Warrant may be executed in any number of counterparts, and
each such counterpart hereof shall be deemed to be an original instrument, but
all such counterparts together shall constitute one Warrant.  This Warrant may
be signed and delivered to the other party by a facsimile transmission; such
transmission shall be deemed a valid signature.

          (g)  Each of the parties shall be responsible for its own costs and
expenses incurred in connection with the transactions contemplated hereby.


                           [Signature page follows]

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          IN WITNESS WHEREOF, the Company has executed this Warrant as of the
7/th/  day of January, 2000.


                                    RIBOZYME PHARMACEUTICALS, INC.


                                    By:_________________________________
                                         Name:
                                         Title:  Chief Executive Officer

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Annex A
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NOTICE OF EXERCISE


To:    Ribozyme Pharmaceuticals, Inc.

1.  The undersigned hereby elects to purchase _____ shares of Common Stock of
Ribozyme Pharmaceuticals, Inc. pursuant to the terms of the attached Warrant,
and tenders herewith full payment of the purchase price of such shares, in cash
or other immediately available funds.

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


_____________________________________(Name)


_____________________________________
_____________________________________(Address)


3.  The undersigned represents that the aforesaid shares are being acquired for
the account of the undersigned for investment and not with a view to, or for
resale in connection with, the distribution thereof and that the undersigned has
no present intention of distributing or reselling such shares.

Signature:__________________________________

Name:_______________________________________

Address:____________________________________

        ____________________________________

        ____________________________________


Social Security or taxpayer identification
number:

__________________________________

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