UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d)

of The Securities Exchange Act of 1934

Date of Report (Date of earliest event reported): January 7, 2020

SUNESIS PHARMACEUTICALS, INC.

(Exact name of registrant as specified in its charter)

Registrant’s telephone number, including area code: (650) 266-3500

Not Applicable

(Former name or former address, if changed since last report.)

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:

 Securities registered pursuant to Section 12(b) of the Act:

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 ☐

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. ☐

As previously reported by Sunesis Pharmaceuticals, Inc., or the Company, on its Current Report on Form 8-K filed on July 9, 2019, the Company received a written notice from the Nasdaq Stock Market LLC, or Nasdaq, indicating that the Company was not in compliance with Nasdaq Listing Rule 5550(a)(2), or the Rule, as the Company’s closing bid price for its common stock was below $1.00 per share for the last 30 consecutive business days. Pursuant to Nasdaq Listing Rule 5810(c)(3)(A), the Company was granted a 180-calendar day compliance period, or until January 6, 2020, to regain compliance with the minimum bid price requirement. Subsequently, on January 7, 2020, the Company requested and was granted a second 180-calendar day compliance period, or until July 6, 2020, to demonstrate compliance.

If the Company does not regain compliance with the Rule by July 6, 2020, the Staff will provide written notification to the Company that its common stock will be subject to delisting. At that time, the Company may appeal the Staff’s delisting determination to a Nasdaq Hearings Panel, or the Panel. The Company would remain listed pending the Panel’s decision. There can be no assurance that, if the Company does appeal the delisting determination by the Staff to the Panel, that such appeal would be successful.

The Company is considering actions that it may take in response to this notification in order to regain compliance with the continued listing requirements. These options include effecting a reverse stock split.

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 hereunto duly authorized.