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                                 July 1, 1998

Mr. Robert S. Whitehead
P.O. Box 877
16140 El Camino Real
Rancho Santa Fe, CA  92067

Dear Bob:

     This letter will serve as the basis by which you will be employed by Dura
Pharmaceuticals, Inc. (the "Company") as its President.

     During your employment beginning July 1, 1998, you will devote your time,
attention and energy  to the Company.  Such service will become full time on or
after October 15, 1998.  In your capacity as President of the Company, you will
perform such executive duties as are from time to time prescribed by the
Chairman & Chief Executive Officer and the Board of Directors of the Company.
Except for certain interim consultant services to be provided to, and serving
on the Board of, Trega Biosciences and Spiros Development Corporation II, Inc.,
you will not, without the prior written consent of the Company's Board of
Directors, directly or indirectly, during the term of your employment: (A)
render significant services of a business, professional or commercial nature to
any other person or entity, either for compensation or otherwise; or (b) engage
in any business activity competitive with or adverse to the Company's business
or welfare, whether alone, as a partner or member, or as an officer, director,
employee or shareholder of another business entity.  The Company will require
you to execute its standard form of employee confidentiality agreement.

     Your beginning compensation and bonus arrangements have been separately
established by prior communication from the Company.  In addition, you will
receive such fringe benefits as are made available generally to executive
employees of the Company.

     The term of your employment will end on July 1, 1999, unless extended by
mutual agreement; provided, however, that unless the Company notifies you at
least nine (9) calendar months prior to any relevant expiration date of its
intention not to renew your employment, your employment will be, at your option
and unless we mutually agree on a larger extension, automatically extended for
additional successive one-year periods.  However, your employment shall
terminate earlier upon (1) your death, (2) in the event you become physically
or mentally disabled so as to become unable, for a period of more than 120
consecutive working days or for more than 120 working days in the aggregate
during any 12-month period, to perform your duties hereunder on substantially a
full-time basis, in which case the Company may, at its option, terminate your
employment hereunder upon not less than thirty (30) days' written notice, (3)
for Cause, and (4) without Cause upon not less than sixty (60) days' written
notice.  For the purposes of this letter agreement, the Company shall have
"Cause" to terminate your employment 

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Mr. Robert S. Whitehead
July 1, 1998
Page 2


hereunder upon (A) your indictment for a felony, or (B) the engaging by you 
in misconduct which is injurious to the Company or any parent, subsidiary or 
affiliate of the Company, or (C) the violation by you of any of the material 
provisions of this letter agreement. If the Company terminates your 
employment without Cause, you will be entitled to six (6) months' base salary 
at the then current annual rate as severance pay unless there has been a 
Change of Control as defined below.  In the event that there has been a 
Change of Control of the Company during the period in which you serve as 
President pursuant to this letter agreement, if the Company terminates your 
employment without Cause or if there is an Involuntary Termination (as 
defined below), you will be entitled to nine (9) months' base salary at the 
then current annual rate as severance pay.  In the event of payment of 
severance under this agreement, stock option vesting shall continue during 
the severance period.  Other than the benefits described in this letter, you 
will not be entitled to any other salary, benefits or bonus subsequent to 
termination.

     The term "Change of Control" shall mean (i) any transaction or series of
related transactions (including but not limited to, any merger or other
reorganization) in which the ownership of more than 50% of the voting power of
the Company is transferred; (ii) a sale, transfer or other disposition of all
or substantially all of the assets of the Company; (iii) the successful
acquisition of thirty percent (30%) or more of the Company's outstanding voting
stock pursuant to a third-party tender or exchange offer; or (iv) a change in
composition of the Board which occurs because the individuals nominated for
election or re-election by majority vote of those members of the Board elected
at the last shareholder meeting at which there were not contested elections for
Board membership fail to be elected or re-elected by the shareholders.

     The term "Involuntary Termination" shall mean the termination of your
employment with the Company: (i) involuntarily by your dismissal without cause;
or (ii) voluntarily or involuntarily following (a) a change in your position
with the Company which materially reduces your level of responsibility; (b) a
reduction of ten percent (10%) or more in your level of compensation (including
base salary, bonuses or fringe benefits); or (c) a change in your place of
employment which is more than twenty (20) miles from your place of employment
prior to the Change of Control, PROVIDED AND ONLY IF such change or reduction
is effected without your written concurrence.

     If a Change of Control of the Company occurs and the Company does not
survive the transaction as an entity, the Company will require the purchaser to
assume the Company's obligations hereunder, and if the purchaser is a
subsidiary of a parent entity, the Company will require the parent entity to
guarantee the performance of the obligations hereunder or to assume directly
the obligations hereunder.

     You also agree that for a period ending three (3) years after a
termination of your employment with the Company, you will not (a) divert,
directly or indirectly, any business of the Company to any other person or
entity; (b) disrupt, damage, impair or interfere with the Company's
relationships with its employees, customers, agents or vendors; (c) directly or

<PAGE>

Mr. Robert S. Whitehead
July 1, 1998
Page 3

indirectly, solicit or otherwise induce any person to leave his or her
employment with the company; or (d) attempt to do any of the foregoing.

     No provisions of this letter agreement may be modified, waived or
discharged unless such waiver, modification or discharge is agreed to in
writing signed by the parties hereto.  No waiver by any party hereto at any
time of any breach by the other party hereto of, or compliance with, any
condition or provision of this letter agreement to be performed by such other
party shall be deemed a waiver of similar or dissimilar provisions or
considerations at the same or at any prior or subsequent time.  This letter
agreement shall be binding upon and inure to the benefit of the Company, its
successors and assigns and you and your heirs, executors, administrators and
legal representatives.  The validity, interpretation, construction and
performance of this letter agreement shall be governed by the laws of the State
of California without reference to conflict of laws.

     This letter agreement shall supersede all prior agreements and
understandings between us, oral or written, with respect to your employment.

     Should this letter reflect your understanding, please sign below and
return one signed copy to me as soon as possible.

                         Very truly yours,

                         DURA PHARMACEUTICALS, INC.


                         /s/ Cam L. Garner
                         ----------------------------------
                         By:  Cam L. Garner
                         Chairman and Chief Executive Officer

ACCEPTED:


/s/ Robert S. Whitehead
-----------------------
Robert S. Whitehead