Washington, D.C. 20549


Pursuant to Section 13 or 15(d)
of the Securities Exchange Act of 1934

Date of report: May 6, 2020
(Date of earliest event reported)

(Exact name of registrant as specified in its charter)

Commission File Number: 1-36282

(State or other jurisdiction of
incorporation or organization)
(I.R.S. Employer
Identification No.)

4550 Towne Centre Court, San Diego, California 92121
(Address of principal executive offices, including zip code)

(858) 207-4264
(Registrant’s telephone number, including area code)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:
Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)
Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)
Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))
Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of the Act:
Title of each class
Name of each exchange
 on which registered
Common Stock, Par Value $0.0001 per share
The Nasdaq Capital Market

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).
Emerging growth company o
If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. o

Item 8.01
Other Events

On May 6, 2020, La Jolla Pharmaceutical Company submitted a non-binding offer to acquire 100% of the equity of Tetraphase Pharmaceuticals, Inc. in an all-cash transaction. A copy of this offer letter is filed herewith as Exhibit 99.1.

Item 9.01.        Financial Statements and Exhibits

(d) Exhibits
Exhibit No.


Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

La Jolla Pharmaceutical Company
May 6, 2020
/s/ Dennis Mulroy
Dennis Mulroy
Chief Financial Officer

Exhibit 99.1

4550 Towne Centre Court | San Diego, California 92121

May 6, 2020

Board of Directors
Tetraphase Pharmaceuticals, Inc.
480 Arsenal Way, Suite 100
Watertown, MA 02472

Dear Members of the Board:

On behalf of La Jolla Pharmaceutical Company, I am pleased to submit this non-binding proposal to acquire 100% of the equity of Tetraphase Pharmaceuticals, Inc. for $22 million in cash plus an additional $12.5 million potentially payable under CVRs to be issued in the transaction. The $22 million upfront consideration would include amounts payable under the Black-Scholes put provisions in Tetraphase’s outstanding warrants and be subject to a minimum, to-be-agreed-upon closing net cash balance. The terms of the CVRs would match those set forth in Tetraphase’s merger agreement with AcelRx Pharmaceuticals, Inc., except that payments pursuant to the CVRs would be made in cash instead of cash or stock at the acquiror’s option.

We are impressed with the growth potential of XERAVA and excited about the potential benefits of combining two companies focused on delivering important therapies to patients in the ICU. Like Tetraphase, La Jolla is dedicated to the development and commercialization of therapies that improve outcomes in critically ill patients. In 2017, La Jolla’s first product, GIAPREZA (angiotensin II), was approved by the FDA as a treatment for septic or other distributive shock. In 2019, GIAPREZA was approved by the European Commission. GIAPREZA net sales were $23.1 million in 2019, up 129% from $10.1 million in 2018. La Jolla’s second product, LJPC‑0118 (artesunate), is under FDA review as a potential treatment for severe malaria.

As of March 31, 2020, La Jolla had $77.2 million of cash and no debt. La Jolla would fund 100% of the purchase price with cash on hand. Accordingly, this offer is not subject to any financing contingencies and would not require a vote by the La Jolla shareholders.

This proposal is subject to due diligence, which we believe we can complete by May 11, 2020. Following completion of our diligence review, we would expect to deliver an execution-ready version of a definitive merger agreement on the same day.

We look forward to discussing our proposal with you further.


Kevin Tang