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                                                                    EXHIBIT 10.3



August 11, 1997


Stephen M. Coutts, Ph.D.
P.O. Box 675666
Rancho Santa Fe, CA  92067-5666

Dear Stephen:

Upon your countersignature below, this letter will be an agreement between you
and La Jolla Pharmaceutical Company (the "Company") and will modify your
existing employment arrangement.

If your employment with the Company is terminated by the Company without cause
(as defined below), you will be entitled to receive from the Company a severance
payment equal to your then-current base salary for a period of nine full
calendar months from the date of termination.

In addition, if a change in control of the Company (as defined in the Company's
1994 Stock Incentive Plan in its form as of the date hereof) occurs and your
employment with the Company or its successor is terminated by the Company or its
successor without cause, then in addition to the severance payment described
above, all employee stock options and other performance awards granted to you
before December 31, 1997 shall automatically vest and become fully exercisable
as of the date of termination of your employment, notwithstanding any vesting or
performance conditions applicable thereto, and shall remain exercisable for a
period of one year following the date of termination of your employment or such
longer period as is provided by the plan or grant pursuant to which such options
or awards were received, provided that in no case will such options or awards be
exercisable beyond the duration of their original term. However, the exercise
period of incentive stock options shall not be extended beyond the termination
date otherwise provided by the award grant unless you elect to forego incentive
stock option treatment and extend the exercise period thereof as provided
herein.

"Cause" means you have (i) engaged in serious criminal activity or other
wrongful conduct that has an adverse impact on the Company, (ii) disregarded
instructions given to you under the authority of the Company's Board of
Directors, (iii) performed services for any other period or entity (other than
the Company and appropriate civic organizations), or (iv) otherwise materially
breached your employment or fiduciary responsibilities to the Company.

Sincerely,

/s/ Steven B. Engle
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Steven B. Engle
Chairman & Chief Executive Officer

AGREED:

/s/ Stephen M. Coutts
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Stephen M. Coutts, Ph.D.
Executive Vice President
Research & Development

Date 8/8/97
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