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                                 EXHIBIT 10.22

March 3, 2000

Stephen N. Rosenfield

Dear Stephen:

On behalf of InterMune Pharmaceuticals, Inc., I am pleased to offer you the
position of Senior Vice President of Legal Affairs and General Counsel reporting
to W. Scott Harkonen, President and CEO.

The terms of your employment will be as follows:

Your starting salary will be $205,000 per year. In addition, you will be
eligible for a bonus of up to 20% of your salary on an annual basis. Also, 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.
You will be entitled to three weeks paid vacation per year. In addition, the
Company will provide you with a one-time sign-on bonus of $50,000, one month
following your first day of employment, and is subject to payback on a prorated
basis if employment is terminated by you before twelve months after your start
date.

Subject to approval of the Board of Directors, on date of hire you will be
granted an option to purchase 140,000 shares of InterMune Pharmaceuticals, Inc.
stock. Your right to exercise the shares of this option will be subject to a
vesting schedule, such that 140,000 shares of your option will be fully vested
at the end of five years completed employment, with vesting with a one year
cliff and monthly thereafter. In the event of a change in control of the
company's ownership and a significant change in your responsibilities at the
company, 100% of your outstanding, unvested options will fully vest. The terms
and conditions of this option, including vesting, will be governed by an
agreement that you will be required to sign.

In the event of termination of your employment with the Company other than for
cause, or a significant change in your responsibilities following a change in
control of the company, you will be entitled to receive continuation of salary
and benefits for six months following your termination date. In addition, you
will be entitled to continue all vesting with respect to Company stock during
such six-month period.

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As a condition of your employment, you will be required to provide proof of U.S.
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 Saturday, March 4, 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 date of your start of hire
is Saturday, March 4, 2000.

Again, let me indicate how pleased I am 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/ W. Scott Harkonen, M.D.
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W. Scott Harkonen, M.D.
President and CEO
InterMune Pharmaceuticals, Inc.


UNDERSTOOD AND ACCEPTED:


/s/  Stephen N. Rosenfield                            3/3/00
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Name Stephen N. Rosenfield                            Date