SecProbe.io

UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, D.C.  20549

        DIVISION OF
  CORPORATION FINANCE

May 13 , 2020

Kevin Tang
Chairman
La Jolla Pharmaceutical Co.
4550 Towne Centre Court
San Diego, California 92121

 Re: La Jolla Pharmaceutical Co.
Schedule TO -C
Filed May  12, 2020 by La Jolla Pharmaceutical Co.
  File No.  005-44849

Dear Mr. Tang :

We have reviewed the above -captioned filing , and have the following comment s.  Please
respond by replying  in writing  to this letter and providing us with any requested additional
information and/or amending the filing .  If you do not believe a comment appl ies to your facts
and circumstances and/or do not believe an amendment is appropriate, please advise  us why .

  After reviewing any amendment to the filing and any information provide d in response to
these comment s, we may have additional comments.

Schedule TO-C

1. The submission made under the EDGAR header tag “SC TO -C” was a Form 8 -K.  The cover
page of the Form 8 -K indicated that  the submission constituted a preliminary communication
within the meaning of Rule 14d -2(b).  As the submission was made exclusively under Form
8-K instead of under cover of Schedule TO, General Instruction A.2. to Form 8 -K required
La Jolla to  “satisf [y] all the substantive requirements of  [Rule 14d -2(b)].”  The submission
did not include the informational legend required by Instruction 3 to Rule 14d -2(b).  Please
confi rm that any fut ure such preliminary communications will include the required legend.

2. The legend required under Instruction 3 must advise security holders,  among other things,  to
read the t ender offer statement when it becomes  available and that they can get the tender
offer statement  for free  from the Commission ’s website.  This disclosure is only useful to the
security holder constituency to whom the tender offer will be made.  As such, future
preliminary communications filed under the EDGAR header tag “SC TO -C” by La Jolla
should  be submitted under the filing history of Tetraphase Pharmaceuticals, Inc.   To the
extent that the above -captioned  initial preliminary filing could not be made under the filing
history of Tetraphase on account of unav ailable access codes, please contact EDGAR filer
support at 202.551.8900 in advance of any additional  preliminary  communications .

Kevin Tang
La Jolla Pharmaceutical Company
May 13, 2020
Page 2

 3. Disclosure under Item 8.01 in the Form 8 -K states La Jolla submitted “a non -binding offer ”
to acquire 100% of the equity of Tetraphase Pharmaceutic als, Inc.   If the term “non-binding
offer” is ascribed a meaning consistent with its plain reading, the  preliminary  communication
suggests  La Jolla has preserved its optionality and may  not proceed with making a tender
offer.  Rule 14e -8(a), however, prohibits a person from publicly announcing  a plan to mak e a
tender offer that has not yet been commenced  if the person  does not have “the intention to
commence the offer within a reasonable time and complete the offer .”  Given La Jolla’s
announcement  of a plan to make a tender offer that has not yet commenced , and such offer
appears subject to material contingencies undisclosed in Item 8.01 , please advise us whether
La Jolla  is preparing to commence a tender offer within a reasonable period  of time .  To the
extent a tender offer i s not timely commenced  by La Jolla , please provide us with a legal
analysis that exp lains when  La Jolla believes it would have liabil ity under Rule 14e -8(a).

*  * *

We remind you that the offerors are  responsible for the accuracy and adequacy of its
disclosures, notwithstanding any  review, comments, action or absence of action by the staff.

  You may contact me at (202) 551 -3266 with any questions.

Sincerely,

        /s/ Nicholas P. Panos

Nicholas P. Panos
Senior Special Counsel
Office of Mergers & Acquisitions

cc: Ryan A. Murr , Esq.