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                                  EXHIBIT 10.6

                             ADVANCED MEDICINE, INC.

                        CHANGE IN CONTROL SEVERANCE PLAN

                                       AND

                            SUMMARY PLAN DESCRIPTION












                        Plan Effective Date: [ ] __, 2000


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                             ADVANCED MEDICINE, INC.
                        CHANGE IN CONTROL SEVERANCE PLAN
                                       AND
                            SUMMARY PLAN DESCRIPTION

The Advanced Medicine, Inc. Change in Control Severance Plan (the "Plan") is
primarily designed to provide eligible employees of Advanced Medicine, Inc. (the
"Corporation") whose employment is terminated in connection with a change in
control occurring after an initial public offering with separation pay and other
benefits in the event of involuntary termination.

This Plan is designed to be an "employee welfare benefit plan," as defined in
Section 3(1) of the Employee Retirement Income Security Act of 1974, as amended
("ERISA"). This Plan is governed by ERISA and, to the extent applicable, the
laws of the State of California. This document constitutes both the official
plan document and the required summary plan description under ERISA.

I.       ELIGIBILITY

You will be eligible for severance benefits under the Plan if:

         -        you are an employee of the Corporation;

         -        your active employment is Involuntarily Terminated other than
                  for Misconduct within the designated period following a Change
                  in Control;

         -        you execute the General Release of All Claims, a copy of which
                  is attached, within the prescribed number of days following
                  your date of termination, as set forth in the attached General
                  Release of All Claims; and

         -        you are NOT in one of the excluded categories listed below.

You are NOT eligible for severance benefits under this Plan if:

         -        you are a temporary employee, part-time employee working fewer
                  than 32 hours per week, probationary employee or student
                  employee;

         -        you are employed with a successor employer following a Change
                  in Control. However, you would be eligible for severance
                  benefits pursuant to the terms of the Plan upon a subsequent
                  Involuntary Termination other than for Misconduct within the
                  designated period following a Change in Control; or

         -        you are dismissed for Misconduct.

II.      HOW THE PLAN WORKS

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If you are eligible for severance benefits under the Plan, the amount of your
severance pay will be determined in accordance with the guidelines set forth
below, subject to the Golden Parachute Tax limitation set forth below:

                              SEVERANCE GUIDELINES

IF YOUR EMPLOYMENT IS INVOLUNTARILY TERMINATED WITHIN TWENTY-FOUR (24) MONTHS
AFTER A CHANGE IN CONTROL, YOU WILL BE PAID:

         -        150% of the Eligible Employee's Annual Base Pay plus Target
                  Bonus, if the Eligible Employee was the Chief Executive
                  Officer of the Corporation immediately before the Change in
                  Control; and

         -        100% of the Eligible Employee's Annual Base Pay plus Target
                  Bonus, if the Eligible Employee was an employee (other than
                  the Chief Executive Officer) of the Corporation immediately
                  before the Change in Control.

ANNUAL BASE PAY generally means your base salary at the rate in effect during
the last regularly scheduled payroll period immediately preceding the occurrence
of the Change in Control and does NOT include, for example, bonuses, overtime
compensation, incentive pay, sales commissions or expense allowances.

TARGET BONUS means 100% of the bonus potential established for you by the
Corporation for the applicable fiscal year.

INVOLUNTARY TERMINATION shall have the meaning assigned to such term in the
Corporation's 2000 Equity Incentive Plan.

MISCONDUCT shall have the meaning assigned to such term in the Corporation's
2000 Equity Incentive Plan.

CHANGE IN CONTROL shall have the meaning assigned to such term in the
Corporation's 2000 Equity Incentive Plan.

GOLDEN PARACHUTE TAX LIMITATION

The Internal Revenue Code imposes a 20% excise tax on certain payments and other
benefits received by certain officers and shareholders in connection with a
change of control involving the Corporation. Such payments can include severance
pay and acceleration of option vesting. In the event that the cash severance
payment you would receive under this Plan, when added to any other payments or
benefits received by you, would (i) constitute a "parachute payment" within the
meaning of Section 280G of the Internal Revenue Code ("Code") and (ii) be
subject to the 20% excise tax imposed by Section 4999 of the Code, then your
cash severance payments shall be either

         -        payable in full or

         -        payable as to such lesser amount which would result in no
                  portion of the


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                  compensation payable to you being subject to excise tax under
                  Section 4999 of the Code,

whichever of the foregoing amounts, taking into account the applicable Federal,
state and local income taxes and the 20% excise tax imposed by Code Section
4999, results in your receipt, on an after-tax basis, of the greatest amount. If
a reduction is to be effected, your bonus severance payment shall be reduced
first and your salary severance payment next. No payments due you outside of
this Plan shall be reduced by reason of this paragraph. Unless you and the
Corporation agree otherwise in writing, any determination required to make this
adjustment shall be made in writing by the Corporation's independent public
accountants or other outside auditors selected by the Corporation immediately
prior to the change of control triggering the parachute payments, whose
determination shall be binding upon you and the Corporation. You and the
Corporation are obligated to furnish to the accountants such information and
documents as the accountants may reasonably request. The Corporation shall bear
all costs of engaging the accountants in connection with these calculations.

III.     OTHER IMPORTANT INFORMATION

PLAN ADMINISTRATION. As the Plan Administrator, the Corporation has full
discretionary authority to administer and interpret the Plan, including
discretionary authority to determine eligibility for benefits under the Plan and
the amount of benefits (if any) payable per participant. Any determination by
the Plan Administrator will be final and conclusive upon all persons. The Plan
Administrator hereby delegates to the Chief Financial Officer all of its
administrative duties. Accordingly, the Chief Financial Officer, on behalf of
the Plan Administrator, has full discretionary authority to carry out its
delegated duties. Any determination by the Chief Financial Officer will be final
and conclusive upon all persons. The Corporation, as the Plan Administrator,
will indemnify and hold harmless the Chief Financial Officer for carrying out
the responsibilities of the Plan Administrator; provided, however, such person
does not act with gross negligence or willful misconduct.

BENEFITS. When benefits are due, they will be paid from the general assets of
the Corporation. The Corporation is not required to establish a trust to fund
the Plan. The benefits provided under this Plan are not assignable and may be
conditioned upon your compliance with any confidentiality agreement you have
entered into with the Corporation or upon your compliance with any Corporation
policy or program.

CLAIMS PROCEDURE. If you believe you are incorrectly denied a benefit or are
entitled to a greater benefit than the benefit you receive under the Plan, you
may submit a signed, written application to the Plan Administrator within ninety
(90) days of your Termination Date. You will be notified of the approval or
denial of this claim within ninety (90) days of the date that the Plan
Administrator receives the claim, unless special circumstances require an
extension of time for processing the claim. If your claim is denied, the
notification will state specific reasons for the denial and you will have sixty
(60) days from receipt of the written notification of the denial of your claim
to file a signed, written request for a review of the denial with the Plan
Administrator. This request should include the reasons you are requesting a
review, facts supporting your


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request and any other relevant comments. Pursuant to its discretionary
authority to administer and interpret the Plan and to determine eligibility
for benefits under the Plan, the Plan Administrator will generally make a
final, written determination of your eligibility for benefits within sixty
(60) days of receipt of your request for review.

PLAN TERMS. This Plan supersedes any and all prior separation, severance and
salary continuation arrangements, programs and plans which were previously
offered by the Corporation, for which you are eligible, but excluding terms of
the Corporation's stock option plans and individual letter agreements which
address the vesting of stock options or restricted stock.

PLAN AMENDMENT OR TERMINATION. The Corporation, acting through its Board of
Directors or its Compensation Committee, reserves the right to terminate or
amend the Plan at any time and in any manner. Any termination or amendment of
the Plan may be made effective immediately with respect to any benefits not yet
paid, whether or not prior notice of such amendment or termination has been
given to affected employees. However, no amendment or termination may be
approved following any Change in Control involving the Corporation.

TAXES.  The Corporation will withhold taxes and other payroll deductions from
any severance payment.

NO RIGHT TO EMPLOYMENT. This Plan does not provide you with any right to
continue employment with the Corporation or affect the Corporation's right,
which right is hereby expressly reserved, to terminate the employment of any
individual at any time for any reason with or without cause.

IV.  STATEMENT OF ERISA RIGHTS

As a participant in the Plan, you are entitled to certain rights and protections
under the Employee Retirement Income Security Act of 1974, as amended ("ERISA").
ERISA provides that all Plan participants shall be entitled to:

         1.       Examine, without charge, at the Plan Administrator's office,
                  all Plan documents, including all documents filed by the Plan
                  with the U.S. Department of Labor.

         2.       Obtain copies of all Plan documents and other Plan information
                  upon written request to the Plan Administrator. The Plan
                  Administrator may make a reasonable charge for the copies.

         3.       File suit in a federal court, if you, as a participant,
                  request materials and do not receive them within thirty (30)
                  days of your request. In such a case, the court may require
                  the Plan Administrator to provide the materials and to pay you
                  a fine of up to $100 for each day's delay until the materials
                  are received, unless the materials were not sent because of
                  reasons beyond the control of the Plan Administrator.

In addition to creating rights for certain employees of the Corporation under
the Plan, ERISA imposes obligations upon the people who are responsible for the
operation of the Plan. The people


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who operate the Plan (called "fiduciaries") have a duty to do so prudently
and in the interest of the Corporation's employees who are covered by the
Plan.

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 benefit to
which you are entitled under the Plan or from exercising your rights under
ERISA.

If your claim for a severance benefit is denied or ignored, in whole or in part,
you have a right to file suit in a federal or a state court. If Plan fiduciaries
are misusing the Plan's assets (if any) or if you are discriminated against for
asserting your rights, you may seek assistance from the U.S. Department of Labor
or file suit in a federal court. The court will decide who will pay court costs
and legal fees. If you are successful in your lawsuit, the court may, if it so
decides, order the party you have sued to pay your legal costs, including
attorney fees. However, if you lose, the court may order you to pay these costs
and fees, for example, if it finds that your claim or suit is frivolous.

If you have any questions about the Plan, this statement or your rights under
ERISA, you should contact the Plan Administrator or the nearest Area Office of
the U.S. Labor-Management Services Administration, Department of Labor.


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                           ADDITIONAL PLAN INFORMATION
<TABLE>

================================================================================
<S>                               <C>
Name of Plan:                     Advanced Medicine, Inc. Change in Control
                                  Severance Plan
--------------------------------------------------------------------------------
Corporation Sponsoring Plan:      Advanced Medicine, Inc.
                                  901 Gateway Boulevard
                                  South San Francisco, CA  94080
                                  650-808-6000
--------------------------------------------------------------------------------
Employer Identification Number:   94-3265960
--------------------------------------------------------------------------------
Plan Number:                      50_

--------------------------------------------------------------------------------
Plan Year:                        The calendar year; the first plan year shall
                                  end December 31, 2000
--------------------------------------------------------------------------------
Plan Administrator:               Advanced Medicine, Inc.
                                  901 Gateway Boulevard
                                  South San Francisco, CA  94080
                                  650-808-6000
--------------------------------------------------------------------------------
Agent for Service of Legal        Plan Administrator
Process:
--------------------------------------------------------------------------------
Type of Plan:                     Severance Plan/Employee Welfare Benefit Plan
--------------------------------------------------------------------------------
Plan Costs:                       The cost of the Plan is paid by Advanced
                                  Medicine, Inc.
================================================================================
</TABLE>


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<PAGE>

                          GENERAL RELEASE OF ALL CLAIMS

         In consideration of the severance benefit to be paid to me by Advanced
Medicine, Inc. under the Advanced Medicine, Inc. Severance Plan, I hereby fully
and forever release and discharge Advanced Medicine, Inc. and its directors,
officers, employees, agents, successors, predecessors, subsidiaries,
shareholders, employee benefit plans and assigns (together called "the
Corporation"), from all claims and causes of action arising out of or relating
in any way to my employment with the Corporation, including the termination of
my employment.

         1. I understand and agree that this RELEASE is a full and complete
waiver of all claims, including (without limitation) claims of wrongful
discharge, breach of contract, breach of the covenant of good faith and fair
dealing, violation of public policy, defamation, personal injury or emotional
distress and claims under Title VII of the Civil Rights Act of 1964, as amended,
the Fair Labor Standards Act, the Equal Pay Act of 1963, the Americans With
Disabilities Act, the Civil Rights Act of 1866, the California Fair Employment
and Housing Act or any other federal or state law or regulation relating to
employment or employment discrimination. I further understand and agree that
this RELEASE is a full and complete waiver of all claims, including (without
limitation) claims under the Employee Retirement Income Security Act of 1974, as
amended (ERISA), related to severance benefits. I further understand that by
this RELEASE I agree not to assist, encourage, institute or cause to be
instituted the filing of any administrative charge or legal proceeding against
the Corporation relating to employment discrimination.

         2. I also hereby agree that nothing contained in this RELEASE shall
constitute or be treated as an admission of liability or wrongdoing by the
Corporation or me.

         3. I agree to abide by the Corporation's Proprietary Information and
Inventions Agreement that I previously executed.

         4. In addition, I hereby expressly waive any and all rights and
benefits conferred upon me by the provisions of Section 1542 of the Civil Code
of the State of California or any analogous provision under any other state law,
which states 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.

         5. I understand that I have until the close of business on __________,
____, to review and consider this RELEASE, discuss it with an attorney of my own
choosing, and decide to execute it or not execute it. I hereby acknowledge that
I have read and understand the foregoing RELEASE and that I sign it voluntarily
and without coercion. I further acknowledge that I was given an opportunity to
consider and review this RELEASE and to consult with an attorney of my own
choosing concerning the waivers contained in this RELEASE and that the waivers
are knowing, conscious and with full appreciation that I am forever foreclosed
from pursuing any of the rights that I waived.


____________,_____        __________________________________________________
                                    Signature

_____________________________________________
Print Full Name


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                    --------------------------------------------
                       YOU ARE ADVISED TO CONSULT AN ATTORNEY
                             BEFORE SIGNING THIS RELEASE.
                    --------------------------------------------

                          GENERAL RELEASE OF ALL CLAIMS

         In consideration of the severance benefit to be paid to me by Advanced
Medicine, Inc. under the Advanced Medicine, Inc. Severance Plan, I hereby fully
and forever release and discharge Advanced Medicine, Inc. and its directors,
officers, employees, agents, successors, predecessors, subsidiaries,
shareholders, employee benefit plans and assigns (together called "the
Corporation"), from all claims and causes of action arising out of or relating
in any way to my employment with the Corporation, including the termination of
my employment.

1. I understand and agree that this RELEASE is a full and complete waiver of all
claims, including (without limitation) claims of wrongful discharge, breach of
contract, breach of the covenant of good faith and fair dealing, violation of
public policy, defamation, personal injury or emotional distress and claims
under Title VII of the Civil Rights Act of 1964, as amended, the Fair Labor
Standards Act, the Equal Pay Act of 1963, the Americans With Disabilities Act,
the Civil Rights Act of 1866, the Age Discrimination in Employment Act of 1967,
as amended (ADEA), the California Fair Employment and Housing Act or any other
federal or state law or regulation relating to employment or employment
discrimination. I further understand and agree that this RELEASE is a full and
complete waiver of all claims, including (without limitation) claims under the
Employee Retirement Income Security Act of 1974, as amended (ERISA), related to
severance benefits. I further understand that by this RELEASE I agree not to
assist, encourage, institute or cause to be instituted the filing of any
administrative charge or legal proceeding against the Corporation relating to
employment discrimination.

                  2. I also hereby agree that nothing contained in this RELEASE
shall constitute or be treated as an admission of liability or wrongdoing by me
or by the Corporation.

                  3. I agree to abide by the Corporation's Proprietary
Information and Inventions Agreement that I previously executed.

                  4. In addition, I hereby expressly waive any and all rights
and benefits conferred upon me by the provisions of Section 1542 of the Civil
Code of the State of California, or any analogous provision under any other
state law, which states 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.

                  5. I hereby acknowledge that I have read and understand the
foregoing RELEASE and that I sign it voluntarily and without coercion. I further
acknowledge that I was given an opportunity to consider and review this RELEASE
and to consult with an attorney of my own choosing concerning the waivers
contained in this RELEASE and that the waivers are knowing, conscious and with
full appreciation that I am forever foreclosed from pursuing any of the rights
that I waived.

                  6. I understand that I have the right to consult with an
attorney before signing this Release. I also understand that, as provided under
the Older Workers Benefit Protection Act of 1990, I have 45 days after receipt
of this RELEASE to review and consider this RELEASE, discuss it with an attorney
of my own choosing, and decide to execute it or not execute it. I also
understand that I may

<PAGE>

revoke this RELEASE during a period of seven days after I sign it and that
this RELEASE will not become effective for seven days after I sign it (and
then only if I do not revoke it). In order to revoke this RELEASE, I must
deliver to the __________ of Advanced Medicine, Inc., within seven days after
I executed this RELEASE, a letter stating that I am revoking it.

         7. I acknowledge that I have been provided with a notice, as required
by the Older Workers Benefit Protection Act of 1990, that contains information
about the individuals covered under the Advanced Medicine, Inc. Change in
Control Severance Plan, the eligibility factors for participation in the Plan,
the time limits applicable to the Plan, the job titles and ages of the employees
designated to participate in the Plan, and the job titles and ages of the
employees who have not been designated to participate in the Plan. (See
ATTACHMENT 1.)

         8. I understand that if I choose to revoke this RELEASE within seven
days after I signed it, I will not receive any severance benefit and the RELEASE
will have no effect.

         9. Before signing my name to this RELEASE, I state that:

I have read it,

I understand it,

I know that I am giving up important rights,

I am aware of my right to consult an attorney before signing it, and

I have signed it knowingly and voluntarily.

____________,_____        __________________________________________________
                                             Signature

_____________________________________________
              Print Full Name


<PAGE>




                                  ATTACHMENT 1

                                  NOTICE ABOUT

          THE ADVANCED MEDICINE, INC. CHANGE IN CONTROL SEVERANCE PLAN

         As required by the Older Workers Benefit Protection Act of 1990, this
notice contains information about the individuals covered under the Advanced
Medicine, Inc. Change in Control Severance Plan (the "Plan"), the eligibility
factors for participation in the Plan, the time limits applicable to the Plan,
the job titles and ages of the employees designated to participate in the Plan,
and the job titles and ages of the employees who have not been designated to
participate in the Plan.

         1. The Plan applies to regular employees of the Corporation whose
employment is terminated following a Change in Control on or after ________ __,
2000, and on or before ________ __, 2000 (provided that they meet the other
requirements of the Plan).

         Employees are not eligible to receive a benefit under the Plan unless
they sign a General Release of All Claims (the "Release"). Employees who have
attained age 40 must return the Release to the Corporation within 45 days after
receiving the form. Once the signed Release is returned to the Corporation, the
employees have seven days to revoke the Release.

         The following is a listing of the ages and job titles of employees of
the Corporation who were and were not selected for termination and participation
in the Plan:


<TABLE>
<CAPTION>
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                    JOB TITLE                         AGE          NUMBER SELECTED          NUMBER NOT SELECTED
<S>                                                <C>             <C>                      <C>
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