Lisa M. Kahle
858.202.2709
lkahle@goodwinprocter.com Goodwin Procter LLP
Counselors at Law
4365 Executive Drive
3rd Floor
San Diego, CA 92121
T: 858.202.2700
F: 858.457.1255

June 28, 2010

Via EDGAR and Fed Ex

Scot Foley
United States Securities and Exchange Commission
Division of Corporation Finance
100 F Street, N.E.
Washington, D.C. 20549

           Re: La Jolla Pharmaceutical Company
Preliminary Proxy Statement on Schedule 14A
Filed June 16, 2010
File No. 000-24274

Dear Mr. Foley:

On behalf of La Jolla Pharmaceutical Company (the “Company”), this letter responds to the comments of the Staff (the “Staff”) of the Securities and Exchange Commission set forth in the letter dated June 23, 2010 relating to the above-referenced Preliminary Proxy Statement. As discussed previously, we submitted proposed changes in response to the Staff’s comments to you via facsimile to dispense with filing an amendment to the Preliminary Proxy Statement and proceeded with filing a Definitive Proxy Statement.

Set forth in italicized print below are the Staff’s comments, as set forth in the June 23, 2010 comment letter, followed by the Company’s responses.

General

1. We note your statement that you have no commitments to issue shares of common stock upon approval of your proposal to amend your certificate of incorporation to increase the number of authorized shares. However, please revise your proxy statement in all relevant parts to state any future plans, arrangements, etc. to issue these newly-authorized shares. If you have no such plans, arrangements, etc. please revise your disclosure to state such

The Company notes the Staff’s comment and has revised its disclosure accordingly.

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Scot Foley
U.S. Securities and Exchange Commission
Division of Corporation Finance
Page 2 of 2

If you have any questions, further comments or require additional information relating to the foregoing, please feel free to contact me.

Sincerely,
 

/s/ Lisa M. Kahle  

Lisa M. Kahle 

cc: Deirdre Y. Gillespie, M.D., La Jolla Pharmaceutical Company
Gail A. Sloan, La Jolla Pharmaceutical Company
Ryan A. Murr, Goodwin Procter LLP

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