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Exhibit 10.5    
    


        [Logo] 


Revised
3/12/98 


March
12, 1998 


John
W. Beck C.P.A.

1035 Inspiration Lane

Escondido, CA 92025 


Dear
John: 


        Metabasis
Therapeutics is pleased to offer you the position of Director of Finance/Controller reporting to Chief Financial Officer of the corporation. 


        The
elements of your employment offer are as follows: 



	1)
	The
base salary for this position is $95,000 per year ($7,916.67/month). A performance and salary review will be conducted on the six-month anniversary of your date of employment. You
will be paid on a biweekly basis.



	2)
	The
salary grade for this position is Grade 18.



	3)
	Your
start date will be as soon as possible but no later than Monday, April 6, 1998. Upon your arrival, please report to me for orientation, at 8:00 a.m. Please note that effective
Friday, March 13, the every day dress code will be established as "business casual".



	4)
	Subject
to approval from the Board of Directors of Gensia Sicor, you will be granted options to purchase 20,000 shares of Gensia Sicor's common stock that will vest over four years.
This grant is effective pursuant to written option agreements under Gensia's Sicor employee stock plan. Subject to adoption of an Metabasis employee stock plan and approval from the Board of
Directors, you will be granted options to purchase shares of the Company's common stock.



	5)
	Metabasis
Therapeutics offers a comprehensive benefits program including medical and dental insurance which becomes effective the first of the month following your date of hire.



	6)
	You
are eligible for vacation and holiday benefits per the provisions of the Company's employee handbook.



	7)
	You
are eligible for consideration under any key employee incentive compensation program implemented for calendar year 1998, per terms and conditions of such program. 




        You
will be expected to execute and deliver a confidentiality/proprietary rights agreement in consideration of your employment. This agreement is enclosed with this letter and
incorporated by reference. 


        In
accordance with the Immigration Reform and Control Act of 1986, you will be required to provide two documents which establish your identity and employment eligibility on your first
day of employment. 


        Employment
is on an at-will basis and can be terminated by yourself or the Company at any time, for any reason and with or without cause and with or without notice. 


        This
letter and the attached proprietary information agreement constitute the entire agreement between us. It supersedes any and all prior agreements and understandings and can not be
changed, except in writing and signed, by both parties. 


METABASIS THERAPEUTICS, INC. — 9390 TOWNE CENTRE DRIVE — SAN DIEGO, CALIFORNIA — 92121-3015 — (619) 587-2770
— FAX (619) 458-3504 





 

        Metabasis Therapeutics is pleased to make you this offer of employment which is good until March 31, 1998. 


        We
eagerly anticipate adding you to the Metabasis team and look forward to working with you. 


        Please
indicate your acceptance of this letter by signing below and returning the enclosed copy along with the confidentiality agreement. 



	

Very truly yours,	

 
	

/s/  PAUL K. LAIKIND      
 Paul K. Laikind, Ph.D.

Chairman of the Board

Business Development and Finance	

 
	

PKL:asd	

 
	

Enclosure	

 
	

Accepted and agreed:	

 
	

/s/  JOHN W. BECK      
 John W. Beck	

 
	

3/17/98
 Date	

 




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Exhibit 10.5