<PAGE>
                                                                   EXHIBIT 10.21

                       INTRABIOTICS PHARMACEUTICALS, INC.

                     SENIOR EXECUTIVE SEVERANCE BENEFIT PLAN

                  AMENDED AND RESTATED EFFECTIVE AUGUST 1, 2002


SECTION 1. INTRODUCTION.

           This IntraBiotics Pharmaceuticals, Inc. Senior Executive Severance
Benefit Plan was established effective July 1, 2001 and amended and restated
effective August 1, 2002 (the "Plan"). The purpose of the Plan is to provide for
the payment of severance benefits to certain eligible employees of IntraBiotics
Pharmaceuticals, Inc. (the "Company") whose employment with the Company is
terminated pursuant to a Covered Termination (as defined below). This Plan shall
supersede any other severance benefit plan (other than the Executive Severance
Benefit Plan, the Director Severance Benefit Plan and the Employee Severance
Benefit Plan), policy or practice previously maintained by the Company. This
Plan document also is the Summary Plan Description for the Plan.

SECTION 2. DEFINITIONS.

           For purposes of the Plan, the following terms are defined as follows:

           (a) "BASE SALARY" means the Eligible Employee's annual base salary as
in effect during the last regularly scheduled payroll period immediately
preceding the effective date of the Covered Termination.

           (b) "BOARD" means the Board of Directors of the Company.

           (c) "COMPANY" means IntraBiotics Pharmaceuticals, Inc.

           (d) "CONSTRUCTIVE TERMINATION" means that the Eligible Employee
voluntarily terminates employment with the Company within thirty (30) days after
any of the following is undertaken without the Eligible Employee's express
written consent:

               (i) a reduction in the Eligible Employee's salary grade;

               (ii) a reduction by the Company in the Eligible Employee's Base
Salary by five percent (5%) or more; provided, however, that a reduction by the
Company of the Eligible Employee's Base Salary by up to ten percent (10%) shall
not constitute a Constructive Termination for purposes of this Plan if it is
made in connection with an across-the-board reduction by the Company of all
Eligible Employees' annual base salaries by a percentage at least equal to the
percentage by which the Eligible Employee's Base Salary is reduced;

               (iii) a relocation of the Eligible Employee's business office to
a location more than fifty (50) miles from the location at which the Eligible
Employee performs his or her duties, except for required travel by the Eligible
Employee on the Company's business to an extent substantially consistent with
the Eligible Employee's business travel obligations;


                                       1.

<PAGE>


provided, however, that no relocation of the Eligible Employee's business office
shall constitute a Constructive Termination for purposes of this Plan if the
Eligible Employee provides services to the Company from a remote location (e.g.,
through telecommuting) at the time of the relocation;

               (iv) a material breach by the Company of any provision of this
Plan; or

               (v) any failure by the Company to obtain the assumption of this
Plan by any successor or assign of the Company.

           (e) "CONTINUATION PERIOD" means the period for which an Eligible
Employee is entitled to receive the salary continuation benefits described in
Section 4(a). The maximum Continuation Period for Eligible Employees, with the
exception of the Chief Executive Officer, shall be fifteen (15) months. The
maximum Continuation Period for the Chief Executive Officer shall be twenty (20)
months.

           (f) "COVERED TERMINATION" means an Involuntary Termination Without
Cause or a Constructive Termination, notice of either of which is given on or
after the Effective Date.

           (g) "EFFECTIVE DATE" means July 1, 2001, the effective date of the
Plan.

           (h) "ELIGIBLE EMPLOYEE" means any full-time, regular hire employee of
the Company who is an Officer of the Company and whose employment with the
Company terminates due to a Covered Termination.

           (i) "ERISA" means the Employee Retirement Income Security Act of
1974, as amended.

           (j) "INVOLUNTARY TERMINATION WITHOUT CAUSE" means the Eligible
Employee's dismissal or discharge for reasons other than Cause. For this
purpose, "Cause" means that, in the reasonable determination of the Company, the
Eligible Employee has

               (i) been indicted for or convicted of or pleaded guilty or no
contest to any felony or any crime involving dishonesty that is likely to
inflict or has inflicted demonstrable and material injury on the business of the
Company;

               (ii) participated in any fraud against the Company;

               (iii) willfully and materially breached a Company policy;

               (iv) intentionally damaged any property of the Company thereby
causing demonstrable and material injury to the business of the Company;

               (v) willfully and materially breached the Eligible Employee's
Proprietary Information and Inventions Agreement with the Company; or



                                       2.

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               (vi) engaged in conduct that, in the reasonable determination of
the Company, demonstrates gross unfitness to serve.

           Notwithstanding the foregoing, Cause shall not exist based on conduct
described in clause (iii) or (vi) above unless the conduct described in such
clause has not been cured within fifteen (15) days following the Eligible
Employee's receipt of written notice from the Company specifying the particulars
of the conduct constituting Cause.

           (k) "OFFICER" means a person who is an officer of the Company within
the meaning of Section 16 of the Securities Exchange Act of 1934, as amended,
and the rules and regulations promulgated thereunder.

           (l) "YEAR OF SERVICE" means any twelve (12) consecutive months of
service with the Company.

SECTION 3. ELIGIBILITY FOR BENEFITS.

           (a) GENERAL RULES. Subject to the requirements set forth in this
Section, the Company shall provide the severance benefits described in Section 4
of the Plan to Eligible Employees.

               (i) In order to be eligible to receive benefits under the Plan,
an Eligible Employee whose employment is terminated pursuant to a Covered
Termination that is an Involuntary Termination Without Cause must continue to
provide services to the Company, at the Company's request, through such date as
determined by the Company; provided, however, that such date shall not be more
than ninety (90) days from the date the Eligible Employee is notified by the
Company, in writing, of his or her Involuntary Termination Without Cause.

               (ii) In order to be eligible to receive benefits under the Plan,
an Eligible Employee also must execute a general waiver and release in
substantially the form attached hereto as Exhibit A, Exhibit B or Exhibit C, as
appropriate, and such release must become effective in accordance with its
terms. The Company, in its sole discretion, may modify the form of the required
release to comply with applicable state law and shall determine the form of the
required release.

           (b) EXCEPTIONS TO BENEFIT ENTITLEMENT. An employee who otherwise is
an Eligible Employee shall not receive benefits under the Plan in any of the
following circumstances, as determined by the Company in its sole discretion:

               (i) The employee has executed an individually negotiated
employment contract or agreement with the Company relating to severance benefits
that is in effect on his or her termination date, in which case such employee's
severance benefit, if any, shall be governed by the terms of such individually
negotiated employment contract or agreement and shall be governed by this Plan
only to the extent that the reduction pursuant to Section 5(a) below does not
entirely eliminate benefits under this Plan.

               (ii) The Company involuntarily terminates the employee's
employment with the Company, and such termination does not constitute a Covered


                                       3.

<PAGE>


Termination. Involuntary terminations include, but are not limited to, a
termination for Cause, as such term is defined in Section 2(j).

               (iii) The employee voluntarily terminates employment with the
Company, and such termination does not constitute a Constructive Termination.
Voluntary terminations include, but are not limited to, resignation, retirement
or failure to return from a leave of absence on the scheduled date.

               (iv) The employee voluntarily terminates employment with the
Company in order to accept employment with another entity that is wholly or
partly owned (directly or indirectly) by the Company or an affiliate of the
Company.

               (v) The employee is offered employment, with the same title and
reporting responsibilities and no diminution in duties and responsibilities,
with the Company, an affiliate of the Company, or a successor to the Company.

               (vi) The employee is rehired by the Company or an affiliate of
the Company prior to the date benefits under the Plan are scheduled to commence.

SECTION 4. AMOUNT OF BENEFIT.

           (a) SALARY CONTINUATION. Each Eligible Employee, with the exception
of the Chief Executive Officer, shall continue to receive Base Salary for a
Continuation Period of nine (9) months plus one (1) month of additional salary
continuation for each complete Year of Service performed by the Eligible
Employee in excess of two (2) Years of Service up to a maximum of fifteen (15)
months. The Chief Executive Officer shall continue to receive Base Salary for a
Continuation Period of twelve (12) months plus one (1) month of additional
salary continuation for each complete Year of Service performed by the Chief
Executive Officer in excess of two (2) Years of Service up to a maximum of
twenty (20) months. Salary continuation shall be paid in regular installments on
the normal payroll dates of the Company and shall be subject to all required tax
withholding. Notwithstanding the foregoing, no salary continuation shall be paid
following the effective date of an Eligible Employee's employment by a
subsequent employer, and Each Eligible Employee shall be required to notify the
Company immediately in writing if the Eligible Employee becomes employed by a
subsequent employer.

           (b) CONTINUED INSURANCE BENEFITS. Provided that the Eligible Employee
elects continued coverage under the Consolidated Omnibus Budget Reconciliation
Act of 1985 ("COBRA"), the Company shall pay the portion of premiums of each
Eligible Employee's group medical, dental and vision coverage, including
coverage for the Eligible Employee's eligible dependents, that the Company paid
prior to the Covered Termination for the Continuation Period described in
Section 4(a) or, if shorter, for the duration of the COBRA continuation period.
Such premium payments shall continue for the duration of the Continuation
Period; provided, however, that no such premium payments shall be made following
the effective date of the Eligible Employee's coverage by a medical, dental or
vision insurance plan of a subsequent employer. Each Eligible Employee shall be
required to notify the Company immediately if the Eligible Employee becomes
covered by a medical, dental or vision insurance plan of a subsequent employer.


                                       4.

<PAGE>


           No provision of this Plan will affect the continuation coverage rules
under COBRA, except that the Company's payment of any applicable insurance
premiums during the Continuation Period will be credited as payment by the
Eligible Employee for purposes of the Eligible Employee's payments required
under COBRA. Therefore, the period during which an Eligible Employee may elect
to continue the Company's group medical coverage at his or her own expense under
COBRA, the length of time during which COBRA coverage will be made available to
the Eligible Employee, and all other rights and obligations of the Eligible
Employee under COBRA (except the obligation to pay insurance premiums that the
Company pays during the Continuation Period) will be applied in the same manner
that such rules would apply in the absence of this Plan. At the conclusion of
the Continuation Period, the Eligible Employee shall be responsible for the
entire payment of premiums required under COBRA for the duration of the COBRA
continuation period. For purposes of this Section 4(b), applicable premiums that
will be paid by the Company during the Continuation Period shall not include any
amounts payable by the Eligible Employee under a Section 125 health care
reimbursement plan, which amounts, if any, are the sole responsibility of the
Eligible Employee.

SECTION 5. LIMITATIONS ON BENEFITS.

           (a) CERTAIN REDUCTIONS AND OFFSETS. Notwithstanding any other
provision of the Plan to the contrary, any benefits payable to an Eligible
Employee under this Plan shall be reduced by any severance benefits payable by
the Company to such individual under any other policy, plan, program or
arrangement, including, without limitation, a contract between the Eligible
Employee and any entity, covering such individual. Furthermore, to the extent
that any federal, state or local laws, including, without limitation, so-called
"plant closing" laws, require the Company to give advance notice or make a
payment of any kind to an Eligible Employee because of that Eligible Employee's
involuntary termination due to a layoff, reduction in force, plant or facility
closing, sale of business, change of control, or any other similar event or
reason, the benefits payable under this Plan shall either be reduced or
eliminated. The benefits provided under this Plan are intended to satisfy any
and all statutory obligations that may arise out of an Eligible Employee's
involuntary termination of employment for the foregoing reasons, and the Plan
Administrator shall so construe and implement the terms of the Plan.

           (b) MITIGATION. Except as otherwise specifically provided herein,
Eligible Employees shall not be required to mitigate damages or the amount of
any payment provided under this Plan by seeking other employment or otherwise,
nor shall the amount of any payment provided for under this Plan be reduced by
any retirement benefits received by such Eligible Employee after the Covered
Termination.

           (c) TERMINATION OF BENEFITS. Benefits under this Plan shall terminate
immediately if the Eligible Employee, at any time, violates any proprietary
information or confidentiality obligation to the Company.

           (d) NON-DUPLICATION OF BENEFITS. No Eligible Employee is eligible to
receive benefits under this Plan more than one time.

           (e) INDEBTEDNESS OF ELIGIBLE EMPLOYEES. If a terminating employee is
indebted to the Company or an affiliate of the Company at his or her termination
date, the


                                       5.

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Company reserves the right to offset any severance payments under the Plan by
the amount of such indebtedness.

           (f) PARACHUTE PAYMENTS. If any payment or benefit the Eligible
Employee would receive in connection with a change in ownership or effective
control of the Company from the Company or otherwise ("Payment") would (i)
constitute a "parachute payment" within the meaning of Section 280G of the
Internal Revenue Code of 1986, as amended (the "Code"), and (ii) but for this
sentence, be subject to the excise tax imposed by Section 4999 of the Code (the
"Excise Tax"), then such Payment shall be equal to the Reduced Amount. The
"Reduced Amount" shall be either (x) the largest portion of the Payment that
would result in no portion of the Payment being subject to the Excise Tax or (y)
the largest portion, up to and including the total, of the Payment, whichever
amount, after taking into account all applicable federal, state and local
employment taxes, income taxes, and the Excise Tax (all computed at the highest
applicable marginal rate), results in the Eligible Employee's receipt, on an
after-tax basis, of the greater amount of the Payment notwithstanding that all
or some portion of the Payment may be subject to the Excise Tax. If a reduction
in payments or benefits constituting "parachute payments" is necessary so that
the Payment equals the Reduced Amount, reduction shall occur in the following
order unless the Eligible Employee elects in writing a different order
(provided, however, that such election shall be subject to Company approval if
made on or after the date on which the event that triggers the Payment occurs):
reduction of cash payments; cancellation of accelerated vesting of stock awards;
reduction of employee benefits. In the event that acceleration of vesting of
stock award compensation is to be reduced, such acceleration of vesting shall be
cancelled in the reverse order of the date of grant of the Eligible Employee's
stock awards unless the Eligible Employee elects in writing a different order
for cancellation.

           The accounting firm engaged by the Company for general audit purposes
as of the day prior to the effective date of the change in ownership or
effective control of the Company shall perform the foregoing calculations. If
the accounting firm so engaged by the Company is serving as accountant or
auditor for the individual, entity or group effecting the change in ownership or
effective control of the Company, the Company shall appoint a nationally
recognized accounting firm to make the determinations required hereunder. The
Company shall bear all expenses with respect to the determinations by such
accounting firm required to be made hereunder.

           The accounting firm engaged to make the determinations hereunder
shall provide its calculations, together with detailed supporting documentation,
to the Company and the Eligible Employee within fifteen (15) calendar days after
the date on which the Eligible Employee's right to a Payment is triggered (if
requested at that time by the Company or the Eligible Employee) or such other
time as requested by the Company or the Eligible Employee. If the accounting
firm determines that no Excise Tax is payable with respect to a Payment, either
before or after the application of the Reduced Amount, it shall furnish the
Company and the Eligible Employee with an opinion reasonably acceptable to
Executive that no Excise Tax will be imposed with respect to such Payment. Any
good faith determinations of the accounting firm made hereunder shall be final,
binding and conclusive upon the Company and the Eligible Employee.



                                       6.

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SECTION 6. RIGHT TO INTERPRET PLAN; AMENDMENT AND TERMINATION.

           (a) EXCLUSIVE DISCRETION. The Plan Administrator shall have the
exclusive discretion and authority to establish rules, forms, and procedures for
the administration of the Plan and to construe and interpret the Plan and to
decide any and all questions of fact, interpretation, definition, computation or
administration arising in connection with the operation of the Plan, including,
but not limited to, the eligibility to participate in the Plan and amount of
benefits paid under the Plan. The rules, interpretations, computations and other
actions of the Plan Administrator shall be binding and conclusive on all
persons.

           (b) AMENDMENT OR TERMINATION. The Company reserves the right to amend
or terminate this Plan or the benefits provided hereunder at any time; provided,
however, that no such amendment or termination shall affect the right to any
unpaid benefit of any Eligible Employee whose termination date has occurred
prior to amendment or termination of the Plan. Any action amending or
terminating the Plan shall be in writing and executed by the chairman of the
Compensation Committee of the Board of Directors of the Company.

SECTION 7. TERMINATION OF CERTAIN EMPLOYEE BENEFITS.

           All non-health benefits (such as life insurance, disability and
401(k) plan coverage) shall terminate as of the employee's termination date
(except to the extent that a conversion privilege may be available thereunder).

SECTION 8. NO IMPLIED EMPLOYMENT CONTRACT.

           The Plan shall not be deemed (i) to give any employee or other person
any right to be retained in the employ of the Company or (ii) to interfere with
the right of the Company to discharge any employee or other person at any time
and for any reason, which right is hereby reserved.

SECTION 9. LEGAL CONSTRUCTION.

           This Plan is intended to be governed by and shall be construed in
accordance with ERISA and, to the extent not preempted by ERISA, the laws of the
State of California.

SECTION 10. CLAIMS, INQUIRIES AND APPEALS.

           (a) APPLICATIONS FOR BENEFITS AND INQUIRIES. Any application for
benefits, inquiries about the Plan or inquiries about present or future rights
under the Plan must be submitted to the Plan Administrator in writing by an
applicant (or his or her authorized representative). The Plan Administrator is:

                       IntraBiotics Pharmaceuticals, Inc.
                             1245 Terra Bella Avenue
                             Mountain View, CA 94043

           (b) DENIAL OF CLAIMS. In the event that any application for benefits
is denied in whole or in part, the Plan Administrator must provide the applicant
with written or electronic


                                       7.

<PAGE>


notice of the denial of the application, and of the applicant's right to review
the denial. Any electronic notice will comply with the regulations of the U.S.
Department of Labor. The written notice of denial will be set forth in a manner
designed to be understood by the employee and will include the following:

               (1) the specific reason or reasons for the denial;

               (2) references to the specific Plan provisions upon which the
denial is based;

               (3) a description of any additional information or material that
the Plan Administrator needs to complete the review and an explanation of why
such information or material is necessary; and

               (4) an explanation of the Plan's review procedures and the time
limits applicable to such procedures, including a statement of the applicant's
right to bring a civil action under section 502(a) of ERISA following a denial
on review of the claim, as described in Section 10(d) below.

           This written notice will be given to the applicant within ninety (90)
days after the Plan Administrator receives the application, unless special
circumstances require an extension of time, in which case, the Plan
Administrator has up to an additional ninety (90) days for processing the
application. If an extension of time for processing is required, written notice
of the extension will be furnished to the applicant before the end of the
initial ninety (90) day period.

           This notice of extension will describe the special circumstances
necessitating the additional time and the date by which the Plan Administrator
is to render its decision on the application. If written notice of denial of the
application for benefits is not furnished within the specified time, the
application shall be deemed to be denied. The applicant will then be permitted
to appeal the denial in accordance with the Review Procedure described below.

           (c) REQUEST FOR A REVIEW. Any person (or that person's authorized
representative) for whom an application for benefits is denied (or deemed
denied), in whole or in part, may appeal the denial by submitting a request for
a review to the Plan Administrator within sixty (60) days after the application
is denied (or deemed denied). A request for a review shall be in writing and
shall be addressed to:

                       IntraBiotics Pharmaceuticals, Inc.
                             1245 Terra Bella Avenue
                             Mountain View, CA 94043

           A request for review must set forth all of the grounds on which it is
based, all facts in support of the request and any other matters that the
applicant feels are pertinent. The applicant (or his or her representative)
shall have the opportunity to submit (or the Plan Administrator may require the
applicant to submit) written comments, documents, records, and other information
relating to his or her claim. The applicant (or his or her representative) shall
be provided, upon request and free of charge, reasonable access to, and copies
of, all documents,


                                       8.

<PAGE>


records and other information relevant to his or her claim. The review shall
take into account all comments, documents, records and other information
submitted by the applicant (or his or her representative) relating to the claim,
without regard to whether such information was submitted or considered in the
initial benefit determination.

           (d) DECISION ON REVIEW. The Plan Administrator will act on each
request for review within sixty (60) days after receipt of the request, unless
special circumstances require an extension of time (not to exceed an additional
sixty (60) days), for processing the request for a review. If an extension for
review is required, written notice of the extension will be furnished to the
applicant within the initial sixty (60) day period. This notice of extension
will describe the special circumstances necessitating the additional time and
the date by which the Plan Administrator is to render its decision on the
review. The Plan Administrator will give prompt, written or electronic notice of
its decision to the applicant. Any electronic notice will comply with the
regulations of the U.S. Department of Labor. In the event that the Plan
Administrator confirms the denial of the application for benefits in whole or in
part, the notice will set forth, in a manner calculated to be understood by the
applicant, the following:

               (1) the specific reason or reasons for the denial;

               (2) references to the specific Plan provisions upon which the
denial is based;

               (3) a statement that the applicant is entitled to receive, upon
request and free of charge, reasonable access to, and copies of, all documents,
records and other information relevant to his or her claim; and

               (4) a statement of the applicant's right to bring a civil action
under section 502(a) of ERISA.

           If written notice of the Plan Administrator's decision is not given
to the applicant within the time prescribed in this Subsection (d), the
application will be deemed denied on review.

           (e) RULES AND PROCEDURES. The Plan Administrator will establish rules
and procedures, consistent with the Plan and with ERISA, as necessary and
appropriate in carrying out its responsibilities in reviewing benefit claims.
The Plan Administrator may require an applicant who wishes to submit additional
information in connection with an appeal from the denial (or deemed denial) of
benefits to do so at the applicant's own expense.

           (f) EXHAUSTION OF REMEDIES. No legal action for benefits under the
Plan may be brought until the claimant (i) has submitted a written application
for benefits in accordance with the procedures described by Section 10(a) above,
(ii) has been notified by the Plan Administrator that the application is denied
(or the application is deemed denied due to the Plan Administrator's failure to
act on it within the established time period), (iii) has filed a written request
for a review of the application in accordance with the appeal procedure
described in Section 10(c) above, and (iv) has been notified in writing that the
Plan Administrator has denied the appeal (or the appeal is deemed to be denied
due to the Plan Administrator's failure to take any action on the claim within
the time prescribed by Section 10(d) above).


                                       9.

<PAGE>


SECTION 11. BASIS OF PAYMENTS TO AND FROM PLAN.

            All benefits under the Plan shall be paid by the Company. The Plan
shall be unfunded, and benefits hereunder shall be paid only from the general
assets of the Company.

SECTION 12. OTHER PLAN INFORMATION.

            (a) EMPLOYER AND PLAN IDENTIFICATION NUMBERS. The Employer
Identification Number assigned to the Company (which is the "Plan Sponsor" as
that term is used in ERISA) by the Internal Revenue Service is 94-3200380. The
Plan Number assigned to the Plan by the Plan Sponsor pursuant to the
instructions of the Internal Revenue Service is 513.

            (b) ENDING DATE FOR PLAN'S FISCAL YEAR. The date of the end of the
fiscal year for the purpose of maintaining the Plan's records is December 31.

            (c) AGENT FOR THE SERVICE OF LEGAL PROCESS. The agent for the
service of legal process with respect to the Plan is IntraBiotics
Pharmaceuticals, Inc., 1245 Terra Bella Avenue, Mountain View, CA 94043.

            (d) PLAN SPONSOR AND ADMINISTRATOR. The "Plan Sponsor" and the "Plan
Administrator" of the Plan is IntraBiotics Pharmaceuticals, Inc., 1245 Terra
Bella Avenue, Mountain View, California 94043. The Plan Sponsor's and Plan
Administrator's telephone number is (650) 526-6800. The Plan Administrator is
the named fiduciary charged with the responsibility for administering the Plan.

SECTION 13. STATEMENT OF ERISA RIGHTS.

            Participants in this Plan (which is a welfare benefit plan sponsored
by IntraBiotics Pharmaceuticals, Inc.) are entitled to certain rights and
protections under ERISA. If you are an Eligible Employee, you are considered a
participant in the Plan and, under ERISA, you are entitled to:

            (a) Examine, without charge, at the Plan Administrator's office and
at other specified locations, such as work sites, all Plan documents and copies
of all documents filed by the Plan with the U.S. Department of Labor, such as
detailed annual reports;

            (b) Obtain copies of all Plan documents and Plan information upon
written request to the Plan Administrator. The Administrator may make a
reasonable charge for the copies; and

            (c) Receive a summary of the Plan's annual financial report, in the
case of a plan that is required to file an annual financial report with the
Department of Labor. (Generally, all pension plans and welfare plans with one
hundred (100) or more participants must file these annual reports.)

            In addition to creating rights for Plan participants, ERISA imposes
duties upon the people responsible for the operation of the employee benefit
plan. The people who operate


                                      10.

<PAGE>


the Plan, called "fiduciaries" of the Plan, have a duty to do so prudently and
in the interest of you and other Plan participants and beneficiaries.

            No one, including your employer or any other person, may fire you or
otherwise discriminate against you in any way to prevent you from obtaining a
Plan benefit or exercising your rights under ERISA. If your claim for a Plan
benefit is denied in whole or in part, you must receive a written explanation of
the reason for the denial. You have the right to have the Plan review and
reconsider your claim.

            Under ERISA, there are steps you can take to enforce the above
rights. For instance, if you request materials from the Plan and do not receive
them within thirty (30) days, you may file suit in a federal court. In such a
case, the court may require the Plan Administrator to provide the materials and
pay you up to $110 a day until you receive the materials, unless the materials
were not sent because of reasons beyond the control of the Plan Administrator.
If you have a claim for benefits that is denied or ignored, in whole or in part,
you may file suit in a state or federal court. If it should happen that the Plan
fiduciaries misuse the Plan's money, or if you are discriminated against for
asserting your rights, you may seek assistance from the U.S. Department of
Labor, or you may file suit in a federal court. The court will decide who should
pay court costs and legal fees. If you are successful, the court may order the
person you have sued to pay these costs and fees. If you lose, the court may
order you to pay these costs and fees, for example, if it finds your claim is
frivolous.

            If you have any questions about the Plan, you should contact the
Plan Administrator. If you have any questions about this statement or about your
rights under ERISA, you should contact the nearest office of the Pension and
Welfare Benefits Administration, U.S. Department of Labor, listed in your
telephone directory or the Division of Technical Assistance and Inquiries,
Pension and Welfare Benefits Administration, U.S. Department of Labor, 200
Constitution Avenue N.W., Washington, D.C. 20210.

SECTION 14. EXECUTION.

            To record the adoption of the Plan, as amended and restated
effective as of August 1, 2002, IntraBiotics Pharmaceuticals, Inc. has caused
its duly authorized officer to execute the same this ____ day of August 2002.

                               INTRABIOTICS PHARMACEUTICALS, INC.


                               By:
                                  ----------------------------------------------

                               Title: Chief Executive Officer
                                      ------------------------------------------


                                      11.

<PAGE>

                                    EXHIBIT A

                                     RELEASE
           (INDIVIDUAL TERMINATION, ELIGIBLE EMPLOYEE AGE 40 OR OLDER)


        I understand and agree completely to the terms set forth in the
IntraBiotics Pharmaceuticals, Inc. Senior Executive Severance Benefit Plan (the
"Plan"). Certain capitalized terms used in this Release are defined in the Plan.

        I hereby confirm my obligations under the Company's proprietary
information and inventions agreement.

        I acknowledge that I have read and understand Section 1542 of the
California Civil Code which reads as follows: "A GENERAL RELEASE DOES NOT EXTEND
TO CLAIMS WHICH THE CREDITOR DOES NOT KNOW OR SUSPECT TO EXIST IN HIS FAVOR AT
THE TIME OF EXECUTING THE RELEASE, WHICH IF KNOWN BY HIM MUST HAVE MATERIALLY
AFFECTED HIS SETTLEMENT WITH THE DEBTOR." I hereby expressly waive and
relinquish all rights and benefits under that section and any law of any
jurisdiction of similar effect with respect to my release of any claims I may
have against the Company.

        Except as otherwise set forth in this Release, I hereby release, acquit
and forever discharge the Company, its parents and subsidiaries, and their
officers, directors, agents, servants, employees, shareholders, successors,
assigns and affiliates, of and from any and all claims, liabilities, demands,
causes of action, costs, expenses, attorneys fees, damages, indemnities and
obligations of every kind and nature, in law, equity, or otherwise, known and
unknown, suspected and unsuspected, disclosed and undisclosed (other than any
claim for indemnification I may have as a result of any third party action
against me based on my employment with the Company), arising out of or in any
way related to agreements, events, acts or conduct at any time prior to and
including the date I execute this Release, including, but not limited to: all
such claims and demands directly or indirectly arising out of or in any way
connected with my employment with the Company or the termination of that
employment, including but not limited to, claims of intentional and negligent
infliction of emotional distress, any and all tort claims for personal injury,
claims or demands related to salary, bonuses, commissions, stock, stock options,
or any other ownership interests in the Company, vacation pay, fringe benefits,
expense reimbursements, severance pay, or any other form of compensation; claims
pursuant to any federal, state or local law or cause of action including, but
not limited to, the federal Civil Rights Act of 1964, as amended; the federal
Age Discrimination in Employment Act of 1967, as amended ("ADEA"); the federal
Employee Retirement Income Security Act of 1974, as amended; the federal
Americans with Disabilities Act of 1990; the California Fair Employment and
Housing Act, as amended; tort law; contract law; wrongful discharge;
discrimination; fraud; defamation; emotional distress; and breach of the implied
covenant of good faith and fair dealing; provided, however, that nothing in this
paragraph shall be construed in any way to release the Company from its
obligation to indemnify me pursuant to the Company's indemnification obligation
pursuant to agreement or applicable law.

        I acknowledge that I am knowingly and voluntarily waiving and releasing
any rights I may have under ADEA. I also acknowledge that the consideration
given under the Plan for the


                                       1.

<PAGE>


waiver and release in the preceding paragraph hereof is in addition to anything
of value to which I was already entitled. I further acknowledge that I have been
advised by this writing, as required by the ADEA, that: (A) my waiver and
release do not apply to any rights or claims that may arise on or after the date
I execute this Release; (B) I have the right to consult with an attorney prior
to executing this Release; (C) I have twenty-one (21) days to consider this
Release (although I may choose to voluntarily execute this Release earlier); (D)
I have seven (7) days following my execution of this Release to revoke the
Release; and (E) this Release shall not be effective until the date upon which
the revocation period has expired, which shall be the eighth (8th) day after I
execute this Release.

                                      EMPLOYEE



                                      Name:
                                           -------------------------------------
                                      Date:
                                           -------------------------------------



                                       2.

<PAGE>

                                    EXHIBIT B

                                     RELEASE
       (INDIVIDUAL AND GROUP TERMINATION, ELIGIBLE EMPLOYEE UNDER AGE 40)


        I understand and agree completely to the terms set forth in the
IntraBiotics Pharmaceuticals, Inc. Senior Executive Severance Benefit Plan (the
"Plan"). Certain capitalized terms used in this Release are defined in the Plan.

        I hereby confirm my obligations under the Company's proprietary
information and inventions agreement.

        I acknowledge that I have read and understand Section 1542 of the
California Civil Code which reads as follows: "A GENERAL RELEASE DOES NOT EXTEND
TO CLAIMS WHICH THE CREDITOR DOES NOT KNOW OR SUSPECT TO EXIST IN HIS FAVOR AT
THE TIME OF EXECUTING THE RELEASE, WHICH IF KNOWN BY HIM MUST HAVE MATERIALLY
AFFECTED HIS SETTLEMENT WITH THE DEBTOR." I hereby expressly waive and
relinquish all rights and benefits under that section and any law of any
jurisdiction of similar effect with respect to my release of any claims I may
have against the Company.

        Except as otherwise set forth in this Release, I hereby release, acquit
and forever discharge the Company, its parents and subsidiaries, and their
officers, directors, agents, servants, employees, shareholders, successors,
assigns and affiliates, of and from any and all claims, liabilities, demands,
causes of action, costs, expenses, attorneys fees, damages, indemnities and
obligations of every kind and nature, in law, equity, or otherwise, known and
unknown, suspected and unsuspected, disclosed and undisclosed (other than any
claim for indemnification I may have as a result of any third party action
against me based on my employment with the Company), arising out of or in any
way related to agreements, events, acts or conduct at any time prior to and
including the date I execute this Release, including, but not limited to: all
such claims and demands directly or indirectly arising out of or in any way
connected with my employment with the Company or the termination of that
employment, including, but not limited to, claims of intentional and negligent
infliction of emotional distress, any and all tort claims for personal injury,
claims or demands related to salary, bonuses, commissions, stock, stock options,
or any other ownership interests in the Company, vacation pay, fringe benefits,
expense reimbursements, severance pay, or any other form of compensation; claims
pursuant to any federal, state or local law or cause of action including, but
not limited to, the federal Civil Rights Act of 1964, as amended; the federal
Age Discrimination in Employment Act of 1967, as amended ("ADEA"); the federal
Employee Retirement Income Security Act of 1974, as amended; the federal
Americans with Disabilities Act of 1990; the California Fair Employment and
Housing Act, as amended; tort law; contract law; wrongful discharge;
discrimination; fraud; defamation; emotional distress; and breach of the implied
covenant of good faith and fair dealing; provided, however, that nothing in this
paragraph shall be construed in any way to release the Company from its
obligation to indemnify me pursuant to the Company's indemnification obligation
pursuant to agreement or applicable law.


                                       1.

<PAGE>


        I understand that I have seven (7) days to consider this Release
(although I may voluntarily execute the Release earlier).



                                  EMPLOYEE



                                  Name:
                                       -----------------------------------------

                                  Date:
                                       -----------------------------------------


                                       2.

<PAGE>

                                    EXHIBIT C

                                     RELEASE
             (GROUP TERMINATION, ELIGIBLE EMPLOYEE AGE 40 OR OLDER)


        I understand and agree completely to the terms set forth in the
IntraBiotics Pharmaceuticals, Inc. Senior Executive Severance Benefit Plan (the
"Plan"). Certain capitalized terms used in this Release are defined in the Plan.

        I hereby confirm my obligations under the Company's proprietary
information and inventions agreement.

        I acknowledge that I have read and understand Section 1542 of the
California Civil Code which reads as follows: "A GENERAL RELEASE DOES NOT EXTEND
TO CLAIMS WHICH THE CREDITOR DOES NOT KNOW OR SUSPECT TO EXIST IN HIS FAVOR AT
THE TIME OF EXECUTING THE RELEASE, WHICH IF KNOWN BY HIM MUST HAVE MATERIALLY
AFFECTED HIS SETTLEMENT WITH THE DEBTOR." I hereby expressly waive and
relinquish all rights and benefits under that section and any law of any
jurisdiction of similar effect with respect to my release of any claims I may
have against the Company.

        Except as otherwise set forth in this Release, I hereby release, acquit
and forever discharge the Company, its parents and subsidiaries, and their
officers, directors, agents, servants, employees, shareholders, successors,
assigns and affiliates, of and from any and all claims, liabilities, demands,
causes of action, costs, expenses, attorneys fees, damages, indemnities and
obligations of every kind and nature, in law, equity, or otherwise, known and
unknown, suspected and unsuspected, disclosed and undisclosed (other than any
claim for indemnification I may have as a result of any third party action
against me based on my employment with the Company), arising out of or in any
way related to agreements, events, acts or conduct at any time prior to and
including the date I execute this Release, including, but not limited to: all
such claims and demands directly or indirectly arising out of or in any way
connected with my employment with the Company or the termination of that
employment, including, but not limited to, claims of intentional and negligent
infliction of emotional distress, any and all tort claims for personal injury,
claims or demands related to salary, bonuses, commissions, stock, stock options,
or any other ownership interests in the Company, vacation pay, fringe benefits,
expense reimbursements, severance pay, or any other form of compensation; claims
pursuant to any federal, state or local law or cause of action including, but
not limited to, the federal Civil Rights Act of 1964, as amended; the federal
Age Discrimination in Employment Act of 1967, as amended ("ADEA"); the federal
Employee Retirement Income Security Act of 1974, as amended; the federal
Americans with Disabilities Act of 1990; the California Fair Employment and
Housing Act, as amended; tort law; contract law; wrongful discharge;
discrimination; fraud; defamation; emotional distress; and breach of the implied
covenant of good faith and fair dealing; provided, however, that nothing in this
paragraph shall be construed in any way to release the Company from its
obligation to indemnify me pursuant to the Company's indemnification obligation
pursuant to agreement or applicable law.

        I acknowledge that I am knowingly and voluntarily waiving and releasing
any rights I may have under ADEA. I also acknowledge that the consideration
given under the Plan for the


                                       1.

<PAGE>


waiver and release in the preceding paragraph hereof is in addition to anything
of value to which I was already entitled. I further acknowledge that I have been
advised by this writing, as required by the ADEA, that: (A) my waiver and
release do not apply to any rights or claims that may arise on or after the date
I execute this Release; (B) I have the right to consult with an attorney prior
to executing this Release; (C) I have forty-five (45) days to consider this
Release (although I may choose to voluntarily execute this Release earlier); (D)
I have seven (7) days following my execution of this Release to revoke the
Release; (E) this Release shall not be effective until the date upon which the
revocation period has expired, which shall be the eighth day (8th) after I
execute this Release; and (F) I have received with this Release a detailed list
of the job titles and ages of all employees who were terminated in this group
termination and the ages of all employees of the Company in the same job
classification or organizational unit who were not terminated.

                                   EMPLOYEE



                                   Name:
                                        ----------------------------------------

                                   Date:
                                        ----------------------------------------


                                       2.