UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 10-Q/A

(Amendment No. 1)

(Mark One)

For the quarterly period ended March 31, 2016

or

For the transition period from                     to                    

Commission file number: 001-36536

CAREDX, INC.

(Exact name of registrant as specified in its charter)

3260 Bayshore Boulevard

Brisbane, California 94005

(Address of principal executive offices and zip code)

(415) 287-2300

(Registrant’s telephone number, including area code)

N/A

(Former name, former address and former fiscal year, if changed since last report)

Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days.     Yes ☒     No ☐

Indicate by check mark whether the registrant has submitted electronically and posted on its corporate Web site, if any, every Interactive Data File required to be submitted and posted pursuant to Rule 405 of Regulation S-T (§232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit and post such files).     Yes ☒     No ☐

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, or a smaller reporting company. See the definitions of “large accelerated filer,” “accelerated filer,” and “smaller reporting company” in Rule 12b-2 of the Exchange Act.

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act).     Yes ☐     No ☒

Indicate the number of shares outstanding of each of the issuer’s classes of common stock, as of the latest practicable date.

There were 13,960,762 shares of the registrant’s Common Stock issued and outstanding as of April 29, 2016.

Explanatory Note

CareDx, Inc. (the “Company”) is filing this Amendment No. 1 (the “Amendment”) to its Form 10-Q for the quarter ended March 31, 2016 (the “Original Form 10-Q”) to correct an inadvertent omission of certain language from paragraph 4 of the certification of its Chief Executive Officer filed as Exhibit 31.1 and the certification of its Chief Financial Officer filed as Exhibit 31.2 to the Original Form 10-Q.

This Amendment should be read in conjunction with the Original Form 10-Q, which continues to speak as of the date thereof. Other than as specifically set forth herein, this Amendment does not modify or update disclosures in the Original Form 10-Q. Accordingly, this Amendment does not reflect events occurring after the filing of the Original Form 10-Q or modify or update any related or other disclosures.

SIGNATURES

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 thereunto duly authorized.

EXHIBIT INDEX