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                                EXHIBIT 10.21

February 21, 2000

Mr. David A. Cory, R.Ph.
7500 Tanglewood Drive
Raleigh, North Carolina 27613

Dear David:

On behalf of InterMune Pharmaceuticals, Inc., we are pleased to offer you the
position of Vice President, Sales and Marketing, reporting to Scott Harkonen,
President and Chief Executive Officer.

The terms of your employment will be as follows:

Your starting salary will be $165,000 per year. As a full-time employee of
InterMune Pharmaceuticals, you will be eligible for the Company's standard
benefits package including medical and dental insurance coverage. Your position
is exempt, and you will not be eligible for overtime. In addition, the Company
provide you with a one-time sign-on bonus of $25,000 one month following your
first day of employment, and is subject to payback on a prorated basis if
employment is terminated before one year. In addition, the Company will provide
you with a $55,000 relocation package to include 6 month temporary housing at
$2,000 per month. The remaining balance is to be used at your discretion.

You will also be eligible for a performance bonus of 20% of your salary, based
on sales targets to be determined at a later date.

Subject to approval of the Board of Directors, on date of hire you will be
granted an option to purchase 100,000 shares of InterMune Pharmaceuticals, Inc.
stock. Your right to exercise the shares of this option will be subject to a
vesting schedule, such that 100,000 shares of your option will be fully vested
at the end of five years completed employment. The terms and conditions of this
option, including vesting, will be governed by an agreement that you will be
required to sign.

As a condition of your employment, you will be required to provide proof of US
citizenship or that you are legally entitled to work in the United States, and
to execute and be bound by the terms of the enclosed Proprietary Information and
Invention Agreement. In that regard, please be aware that Company policy
prohibits all employees from bringing to the Company, or using in performance of
their responsibilities at the Company, any confidential information, trade
secrets, or propriety material or processes of any previous employer. Employment
with the Company is at will, is not for any specific term and can be terminated
by you or the Company at any time for any reason with or without cause.

This offer remains open through Monday, February 28, 2000. Upon acceptance of
this offer, the terms described in this letter and in the Proprietary
Information and Invention Agreement shall be the terms of your employment,
superseding any other employment agreements or understandings with InterMune.
Any additions or modifications of these terms must be in writing and signed by
you and an officer of InterMune Pharmaceuticals, Inc. Your anticipated start
date will be on or before March 13, 2000.

Again, let me indicate how pleased we are to extend this offer, and how much we
at InterMune look forward to working with you. We anticipate that you will find
this an exciting and challenging position in a dynamic and growing company.

Please indicate your acceptance by signing and returning the enclosed duplicate
original of this letter to me.

Very truly yours,

/s/ Scott Harrison, M.D.

W. Scott Harkonen, M.D.
President and Chief Executive Officer

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UNDERSTOOD AND ACCEPTED:


/s/ David Cory                              2/28/00
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David Cory                                  Date