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                                                                  EXHIBIT 10.15

                                                                      NO. PHW-2

     THE SECURITIES REPRESENTED HEREBY HAVE NOT BEEN REGISTERED UNDER THE
SECURITIES ACT OF 1933, AS AMENDED (THE "ACT"), OR UNDER THE SECURITIES LAWS
OF ANY STATE.  THESE SECURITIES ARE SUBJECT TO RESTRICTIONS ON
TRANSFERABILITY AND RESALE AND MAY NOT BE TRANSFERRED OR RESOLD EXCEPT AS
PERMITTED UNDER THE ACT AND APPLICABLE STATE SECURITIES LAWS, PURSUANT TO
REGISTRATION OR EXEMPTION THEREFROM.  THE ISSUER OF THESE SECURITIES MAY
REQUIRE AN OPINION OF COUNSEL IN FORM AND SUBSTANCE REASONABLY SATISFACTORY
TO THE ISSUER TO THE EFFECT THAT ANY PROPOSED TRANSFER OR RESALE IS IN
COMPLIANCE WITH THE ACT AND ANY APPLICABLE STATE SECURITIES LAWS.

                         WARRANT TO PURCHASE 100,000 SHARES

                          OF SERIES H PREFERRED STOCK OF
                         INTRABIOTICS PHARMACEUTICALS, INC.
                           (VOID AFTER DECEMBER 31, 2001)

     This certifies that Vulcan Ventures, Inc. or its permitted assigns (the
"Holder"), for value received, is entitled to purchase from INTRABIOTICS
PHARMACEUTICALS, INC., a Delaware corporation (the "Company"), having a place
of business 1255 Terra Bella, Mountain View, California, a maximum of One
Hundred Thousand (100,000) fully paid and nonassessable shares of the
Company's Series H Preferred Stock ("Preferred Stock") for cash at a price
equal to $5.00 per share (the "Stock Purchase Price") at any time or from
time to time up to and including 5:00 p.m. (Pacific time) on December 31,
2001 (the "Expiration Date") upon surrender to the Company at its principal
office (or at such other location as the Company may advise the Holder in
writing) of this Warrant properly endorsed with the Form of Subscription
attached hereto duly filled in and signed and upon payment in cash or wire
transfer of the aggregate Stock Purchase Price for the number of shares for
which this Warrant is being exercised determined in accordance with the
provisions hereof. The Stock Purchase Price and the number of shares
purchasable hereunder are subject to adjustment as provided in Section 3 of
this Warrant.

     This Warrant is subject to the following terms and conditions:

     1.   EXERCISE; ISSUANCE OF CERTIFICATES; PAYMENT FOR SHARES.  This
Warrant is exercisable at the option of the holder of record hereof, at any
time or from time to time, up to the Expiration Date for all or any part of
the shares of Preferred Stock (but not for a fraction of a share) which may
be purchased hereunder.  The Company agrees that the shares of Preferred
Stock purchased under this Warrant shall be and are deemed to be issued to
the Holder hereof as the record owner of such shares as of the close of
business on the date on which this Warrant shall have been surrendered,
properly endorsed, the completed, executed Form of Subscription delivered and
payment made for such shares. Certificates for the shares of Preferred Stock
so purchased, together with any other securities or property to which the
Holder hereof is entitled upon such exercise, shall be delivered to the
Holder hereof by the Company at the Company's

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expense within a reasonable time after the rights represented by this Warrant
have been so exercised.  In case of a purchase of less than all the shares
which may be purchased under this Warrant, the Company shall cancel this
Warrant and execute and deliver a new Warrant or Warrants of like tenor for
the balance of the shares purchasable under the Warrant surrendered upon such
purchase to the Holder hereof within a reasonable time.  Each stock
certificate so delivered shall be in such denominations of Preferred Stock as
may be requested by the Holder hereof and shall be registered in the name of
such Holder.

     2.   SHARES TO BE FULLY PAID; RESERVATION OF SHARES.  The Company
covenants and agrees that all shares of Preferred Stock which may be issued
upon the exercise of the rights represented by this Warrant will, upon
issuance, be duly authorized, validly issued, fully paid and nonassessable
and free from all preemptive rights of any shareholder and free of all taxes,
liens and charges with respect to the issue thereof.  The Company further
covenants and agrees that, during the period within which the rights
represented by this Warrant may be exercised, the Company will at all times
have authorized and reserved, for the purpose of issue or transfer upon
exercise of the subscription rights evidenced by this Warrant, a sufficient
number of shares of authorized but unissued Preferred Stock, or other
securities and property, when and as required to provide for the exercise of
the rights represented by this Warrant.  The Company will take all such
action as may be necessary to assure that such shares of Preferred Stock may
be issued as provided herein without violation of any applicable law or
regulation, or of any requirements of any domestic securities exchange upon
which the Preferred Stock may be listed; PROVIDED, HOWEVER, that the Company
shall not be required to effect a registration under federal or state
securities laws with respect to such exercise.  The Company will not take any
action which would result in any adjustment of the Stock Purchase Price (as
set forth in Section 3 hereof) (i) if the total number of shares of Preferred
Stock issuable after such action upon exercise of all outstanding warrants,
together with all shares of Preferred Stock then outstanding and all shares
of Preferred Stock then issuable upon exercise of all options and upon the
conversion of all convertible securities then outstanding, would exceed the
total number of shares of Preferred Stock then authorized by the Company's
Certificate of Incorporation, or (ii) if the total number of shares of Common
Stock issuable after such action upon the conversion of all such shares of
Preferred Stock, together with all shares of Common Stock then issuable upon
exercise of all options and upon the conversion of all such shares of
Preferred Stock, together with all shares of Common Stock then outstanding
and all shares of Common Stock then issuable upon exercise of all options and
upon the conversion of all convertible securities then outstanding would
exceed the total number of shares of Common Stock then authorized by the
Company's Certificate of Incorporation.

     3.   ADJUSTMENT OF STOCK PURCHASE PRICE AND NUMBER OF SHARES.  The Stock
Purchase Price and the number of shares purchasable upon the exercise of this
Warrant shall be subject to adjustment from time to time upon the occurrence
of certain events described in this Section 3.  Upon each adjustment of the
Stock Purchase Price, the Holder of this Warrant shall thereafter be entitled
to purchase, at the Stock Purchase Price resulting from such adjustment, the
number of shares obtained by multiplying the Stock Purchase Price in effect
immediately prior to such adjustment by the number of shares purchasable
pursuant hereto immediately prior to such

                                       2.

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adjustment, and dividing the product thereof by the Stock Purchase Price
resulting from such adjustment.

          3.1  SUBDIVISION OR COMBINATION OF STOCK.  In case the Company
shall at any time subdivide its outstanding shares of Preferred Stock into a
greater number of shares, the Stock Purchase Price in effect immediately
prior to such subdivision shall be proportionately reduced, and conversely,
in case the outstanding shares of Preferred Stock of the Company shall be
combined into a smaller number of shares, the Stock Purchase Price in effect
immediately prior to such combination shall be proportionately increased.

          3.2  DIVIDENDS IN PREFERRED STOCK, OTHER STOCK, PROPERTY,
RECLASSIFICATION.  If at any time or from time to time the Holders of
Preferred Stock (or any shares of stock or other securities at the time
receivable upon the exercise of this Warrant) shall have received or become
entitled to receive, without payment therefor,

               (a)  Preferred Stock or any shares of stock or other
securities which are at any time directly or indirectly convertible into or
exchangeable for Preferred Stock, or any rights or options to subscribe for,
purchase or otherwise acquire any of the foregoing by way of dividend or
other distribution,

               (b)  any cash paid or payable otherwise than as a cash
dividend, or

               (c)  Preferred Stock or additional stock or other securities
or property (including cash) by way of spinoff, split-up, reclassification,
combination of shares or similar corporate rearrangement, (other than shares
of Preferred Stock issued as a stock split or adjustments in respect of which
shall be covered by the terms of Section 3.1 above), then and in each such
case, the Holder hereof shall, upon the exercise of this Warrant, be entitled
to receive, in addition to the number of shares of Preferred Stock receivable
thereupon, and without payment of any additional consideration therefor, the
amount of stock and other securities and property (including cash in the
cases referred to in clause (b) above and this clause (c)) which such Holder
would hold on the date of such exercise had he been the holder of record of
such Preferred Stock as of the date on which holders of Preferred Stock
received or became entitled to receive such shares or all other additional
stock and other securities and property.

          3.3  REORGANIZATION, RECLASSIFICATION, CONSOLIDATION, MERGER OR
SALE. If any recapitalization, reclassification or reorganization of the
capital stock of the Company, or any consolidation or merger of the Company
with another corporation, or the sale of all or substantially all of its
assets or other transaction shall be effected in such a way that holders of
Preferred Stock shall be entitled to receive stock, securities, or other
assets or property (an "Organic Change"), then, as a condition of such
Organic Change, lawful and adequate provisions shall be made by the Company
whereby the Holder hereof shall thereafter have the right to purchase and
receive (in lieu of the shares of the Preferred Stock of the Company
immediately theretofore purchasable and receivable upon the exercise of the
rights represented hereby) such shares of stock, securities or other assets
or property as may be issued or payable with respect to

                                       3.

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or in exchange for a number of outstanding shares of such Preferred Stock
equal to the number of shares of such stock immediately theretofore
purchasable and receivable upon the exercise of the rights represented
hereby; PROVIDED, HOWEVER, that in the event the value of the stock,
securities or other assets or property (determined in good faith by the Board
of Directors of the Company) issuable or payable with respect to one share of
the Preferred Stock of the Company immediately theretofore purchasable and
receivable upon the exercise of the rights represented hereby is in excess of
the Stock Purchase Price hereof effective at the time of a merger and
securities received in such reorganization, if any, are publicly traded, then
this Warrant shall expire unless exercised prior to such Organic Change.  In
the event of any Organic Change, appropriate provision shall be made by the
Company with respect to the rights and interests of the Holder of this
Warrant to the end that the provisions hereof (including, without limitation,
provisions for adjustments of the Stock Purchase Price and of the number of
shares purchasable and receivable upon the exercise of this Warrant) shall
thereafter be applicable, in relation to any shares of stock, securities or
assets thereafter deliverable upon the exercise hereof.  The Company will not
effect any such consolidation, merger or sale unless, prior to the
consummation thereof, the successor corporation (if other than the Company)
resulting from such consolidation or the corporation purchasing such assets
shall assume by written instrument the obligation to deliver to such Holder
such shares of stock, securities or assets as, in accordance with the
foregoing provisions, such Holder may be entitled to purchase.

          3.4  CERTAIN EVENTS.  If any change in the outstanding Preferred
Stock of the Company or any other event occurs as to which the other
provisions of this Section 3 are not strictly applicable or if strictly
applicable would not fairly protect the purchase rights of the Holder of the
Warrant in accordance with such provisions, then the Board of Directors of
the Company shall make an adjustment in the number and class of shares
available under the Warrant, the Stock Purchase Price or the application of
such provisions, so as to protect such purchase rights as aforesaid.  The
adjustment shall be such as will give the Holder of the Warrant upon exercise
for the same aggregate Stock Purchase Price the total number, class and kind
of shares as he would have owned had the Warrant been exercised prior to the
event and had he continued to hold such shares until after the event
requiring adjustment.

          3.5  NOTICES OF CHANGE.

               (a)  Immediately upon any adjustment in the number or class of
shares subject to this Warrant and of the Stock Purchase Price, the Company
shall give written notice thereof to the Holder, setting forth in reasonable
detail and certifying the calculation of such adjustment.

               (b)  The Company shall give written notice to the Holder at
least 10 calendar days prior to the date on which the Company closes its
books or takes a record for determining rights to receive any dividends or
distributions.

               (c)  The Company shall give written notice to the Holder at
least 20 calendar days prior to the date on which an Organic Change shall
take place.

                                       4.

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               (d)  The Company shall give written notice to the Holder at
least 20 calendar days prior to the Closing of the Initial Public Offering.

     4.   ISSUE TAX.  The issuance of certificates for shares of Preferred
Stock upon the exercise of the Warrant shall be made without charge to the
Holder of the Warrant for any issue tax (other than any applicable income
taxes) in respect thereof; PROVIDED, HOWEVER, that the Company shall not be
required to pay any tax which may be payable in respect of any transfer
involved in the issuance and delivery of any certificate in a name other than
that of the then Holder of the Warrant being exercised.

     5.   CLOSING OF BOOKS.  The Company will at no time close its transfer
books against the transfer of any warrant or of any shares of Preferred Stock
issued or issuable upon the exercise of any warrant in any manner which
interferes with the timely exercise of this Warrant.

     6.   NO VOTING OR DIVIDEND RIGHTS; LIMITATION OF LIABILITY.  Nothing
contained in this Warrant shall be construed as conferring upon the Holder
hereof the right to vote or to consent or to receive notice as a shareholder
of the Company or any other matters or any rights whatsoever as a shareholder
of the Company.  No dividends or interest shall be payable or accrued in
respect of this Warrant or the interest represented hereby or the shares
purchasable hereunder until, and only to the extent that, this Warrant shall
have been exercised.  No provisions hereof, in the absence of affirmative
action by the holder to purchase shares of Preferred Stock, and no mere
enumeration herein of the rights or privileges of the holder hereof, shall
give rise to any liability of such Holder for the Stock Purchase Price or as
a shareholder of the Company, whether such liability is asserted by the
Company or by its creditors.

     7.   WARRANTS TRANSFERABLE.  This Warrant is not transferable except to
an affiliate of Holder; PROVIDED that Holder provides written notice of such
transfer to the Company, such transferee agrees to be bound by the
obligations hereunder, and the Company may treat such transferee as the
absolute owner hereof for any purpose and as the person entitled to exercise
the rights represented by this Warrant.

     8.   "MARKET-STAND-OFF" AGREEMENT. If requested by the Company, or the
representative of the underwriters of the Initial Public Offering, Holder
agrees not to sell or otherwise transfer or dispose of the shares of
Preferred Stock issuable upon exercise of this Warrant, or the shares of
Common Stock issuable upon conversion thereof, for a period specified by such
representative of the underwriters not to exceed one hundred eighty (180)
days following the date of the final prospectus forming part of the
registration statement filed pursuant to the Initial Public Offering.

     9.   RIGHTS AND OBLIGATIONS SURVIVE EXERCISE OF WARRANT.  The rights and
obligations of the Company, of the holder of this Warrant and of the holder
of shares of Preferred Stock issued upon exercise of this Warrant, shall
survive the exercise of this Warrant.

                                       5.

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     10.  MODIFICATION AND WAIVER.  This Warrant and any provision hereof may
be changed, waived, discharged or terminated only by an instrument in writing
signed by the party against which enforcement of the same is sought.

     11.  NOTICES.  Any notice, request or other document required or
permitted to be given or delivered to the holder hereof or the Company shall
be delivered or shall be sent by certified mail, postage prepaid, to each
such holder at its address as shown on the books of the Company or to the
Company at the address indicated therefor in the first paragraph of this
Warrant or such other address as either may from time to time provide to the
other.

     12.  BINDING EFFECT ON SUCCESSORS.  This Warrant shall be binding upon
any corporation succeeding the Company by merger, consolidation or
acquisition of all or substantially all of the Company's assets.  All of the
obligations of the Company relating to the Preferred Stock issuable upon the
exercise of this Warrant shall survive the exercise and termination of this
Warrant.  All of the covenants and agreements of the Company shall inure to
the benefit of the successors and assigns of the holder hereof.

     13.  DESCRIPTIVE HEADINGS AND GOVERNING LAW.  The description headings
of the several sections and paragraphs of this Warrant are inserted for
convenience only and do not constitute a part of this Warrant.  This Warrant
shall be construed and enforced in accordance with, and the rights of the
parties shall be governed by, the laws of the State of California.

     14.  LOST WARRANTS.  The Company represents and warrants to the Holder
hereof 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 an indemnity
reasonably satisfactory to the Company, or in the case of any such mutilation
upon surrender and cancellation of such Warrant, the Company, at its expense,
will make and deliver a new Warrant, of like tenor, in lieu of the lost,
stolen, destroyed or mutilated Warrant.

     15.  FRACTIONAL SHARES.  No fractional shares shall be issued upon
exercise of this Warrant.  The Company shall, in lieu of issuing any
fractional share, pay the holder entitled to such fraction a sum in cash
equal to such fraction multiplied by the then effective Stock Purchase Price.

                       [This Space Intentionally Left Blank]


                                       6.

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     IN WITNESS WHEREOF, the Company has caused this Warrant to be duly
executed by its officers, thereunto duly authorized this 15th day of
October, 1999.


                                      INTRABIOTICS PHARMACEUTICALS, INC.,
                                      a Delaware corporation

                                      By: /s/ Kenneth J. Kelley
                                         ----------------------------------
                                          Kenneth J. Kelley, President and CEO



HOLDER:


By: /s/ William D. Savoy
    -----------------------------

    Vice President
    -----------------------------
    Printed Name and Title


Address:  _______________________
          _______________________
          _______________________