Delaware

0-26483

94-3236309

(State or Other Jurisdiction

of Incorporation)

(Commission

File Number)

(IRS Employer Identification Number)

349 Oyster Point Boulevard, South San Francisco, California

94080

(Address of Principal Executive Offices)

(Zip Code)

£

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))

(a)

Dismissal of Independent Registered Public Accounting Firm

i.

On March 31, 2016, Diadexus Inc. (the “Company”) dismissed PricewaterhouseCoopers LLP (“PwC”) as its independent registered public accounting firm. The decision to change Diadexus’ independent registered public accounting firm was approved by the Audit Committee of the Board of Directors (“Audit Committee”) of the Company on March 31, 2016.

ii.

PwC’s reports on Diadexus’ financial statements for the fiscal years ended December 31, 2015 and 2014 contained no adverse opinion or disclaimer of opinion, and were not qualified or modified as to uncertainty, audit scope or accounting principles, except that PwC’s audit report on the December 31, 2015 financial statements contained an explanatory paragraph expressing substantial doubt regarding the Company’s ability to continue as a going concern.

iii.

During the fiscal years ended December 31, 2015 and 2014 and in the subsequent interim period through March 31, 2016, there have been no disagreements between the Company and PwC on any matter of accounting principles or practices, financial statement disclosure or auditing scope or procedure, which disagreements, if not resolved to the satisfaction of PwC, would have caused them to make reference thereto in their reports on the financial statements for such years.

iv.

During the fiscal years ended December 31, 2015 and 2014 and the subsequent interim period through March 31, 2016, there were no reportable events, as that term is defined in Item 304(a)(1)(v) of Regulation S-K.

v.

The Company has requested that PwC furnish it with a letter addressed to the U.S. Securities and Exchange Commission stating whether or not PwC agrees with the above statements. A copy of such letter, dated April 1, 2016, is filed as Exhibit 16.1 to this Current Report on Form 8-K.

(b)

Appointment of New Independent Registered Public Accounting Firm

i.

Contemporaneous with the decision to dismiss PwC, the Audit Committee also approved the appointment of OUM & Co. LLP (“OUM”) as its new independent registered public accounting firm, effective March 31, 2016. During the fiscal years ended December 31, 2015 and 2014 and the subsequent interim period through March 31, 2016, the Company has not consulted with OUM regarding either (1) the application of accounting principles to a specific transaction, either completed or proposed; or the type of audit opinion that might be rendered on the Company’s financial statements, and no written report or oral advice was provided to the Company that OUM concluded was an important factor considered by the Company in reaching a decision as to any accounting, auditing, or financial reporting issue; or (2) any matter that was the subject of a disagreement, as that term is defined in Item 304(a)(1)(iv) of Regulation S-K and the related instructions, or a reportable event, as that term is defined in Item 304 (a)(1) (v) of Regulation S-K.

Exhibit No.

Description

16.1

Letter of PricewaterhouseCoopers LLP, dated April 1, 2016

Diadexus, Inc.

(Registrant)

Date: March 31, 2016

By:

/s/ Leone D. Patterson

Leone D. Patterson

Vice President, Finance and Chief Financial Officer

Exhibit No.

Description

16.1

Letter of PricewaterhouseCoopers LLP, dated April 1, 2016, regarding change in independent registered public accounting firm.