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                                                                    EXHIBIT 10.6



                     AMENDMENT NO. 1 TO EMPLOYMENT AGREEMENT


     This Amendment No. 1 to Employment Agreement (this "AMENDMENT") is made
effective as of June 26, 1997 by and between La Jolla Pharmaceutical Company, a
Delaware corporation (the "COMPANY") and Steven B. Engle ("EXECUTIVE").

     Executive and the Company are parties to that certain Employment Agreement
(the "AGREEMENT") dated as of December 30, 1993 pursuant to which Executive is
employed by the Company, and desire to amend the Agreement as set forth herein
in consideration of Executive's ongoing employment.

     Therefore, notwithstanding anything in the Agreement to the contrary, the
Company and Executive hereby agree as follows:

     1. Executive shall be employed by the Company as its President and Chief
Executive Officer, shall perform such duties as are consistent with such
position, and shall report to the Company's Board of Directors.

     2. As compensation for his services to the Company, Executive shall receive
a base salary of at least $240,000 per annum (as such amount may be increased
from time to time by the Company's Board of Directors, the "BASE SALARY").

     3. (a) If Executive's employment with the Company is terminated by the
Company other than for cause as defined in Section 6.1 of the Agreement, or 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 Executive's
employment with the Company or its successor is terminated by the Company or its
successor, or if such a Change in Control occurs and Executive's employment with
the Company or its successor is terminated by Executive following any change in
Executive's title to any position other than President or CEO of the surviving
company, or any change in Executive's reporting responsibility such that he does
not report directly to the CEO or board of directors of the surviving company on
all matters, or any material reduction by the Company or its successor in
Executive's responsibilities (other than any such reduction that is commensurate
with Executive's assumption of the position of President of the surviving
company with another person serving as CEO), or any requirement that Executive's
place of employment be in other than the San Diego area, then, in addition to
any other benefits provided under the Agreement that may be applicable:

          (i) the Company (or its successor, as the case may be) shall pay to
Executive a severance payment (the "SEVERANCE PAYMENT") equal to the
then-current Base Salary for a period of twelve full calendar months from the
date of termination of Executive's employment (the "TERMINATION DATE"); and

          (ii) the Company (or its successor, as the case may be) shall
continue, at its sole expense, all of Executive's medical, dental and life
insurance coverage until the earlier of 



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(A) twelve full calendar months from the Termination Date, or (B) such time as
Executive receives similar paid coverage from another employer; and

          (iii) all employee stock options and other performance awards granted
to Executive before December 31, 1997 shall automatically vest and become fully
exercisable as of the Termination Date, notwithstanding any vesting or
performance conditions applicable thereto, and shall remain exercisable for a
period of one year following the Termination Date 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 the original term thereof, and provided further that
nothing herein is intended to require the extension of the exercise period of
any option that qualifies as an incentive stock option under the Internal
Revenue Code and applicable regulations thereunder, and the exercise period
thereof shall not be extended beyond the termination date otherwise provided by
the award grant unless Executive, in his sole and unqualified discretion, elects
to forego incentive stock option treatment and extend the exercise period
thereof as provided herein.

          (b) The Severance Payment shall be payable in equal periodic
installments from the Termination Date consistent with the normal payroll
practices of the Company (or its successor, as the case may be), provided,
however, that Executive shall have the right, at any time in his discretion, to
receive the remaining balance of the Severance Payment in a lump sum discounted
to present value at a rate equal to the "Reference Rate" announced by Bank of
America NT & SA as of the time of Executive's election to receive a lump sum.
Executive shall exercise his right to receive a lump sum payment of the
Severance Payment by delivering written notice to the Company, and the Company
shall pay the lump sum within ten (10) days of receipt of such notice.

     4. To the extent of any inconsistency between the text of the original
Agreement and this Amendment, this Amendment shall govern, provided that nothing
in this Amendment shall be construed to limit benefits to which Executive is
entitled under the Agreement in addition to those conferred by this Amendment,
and to the extent not subsumed within the benefits provided by this Amendment,
benefits provided under the Agreement shall remain in effect.

     IN WITNESS WHEREOF, Executive and the Company have entered into this
Amendment as of the date written above.

LA JOLLA PHARMACEUTICAL COMPANY

By: /s/ Wood Erwin                     /s/ Steven B. Engle
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Name: Wood Erwin                           STEVEN  B. ENGLE
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Title: V.P. Finance & CFO
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