PRTO Proteon Therapeutics Inc

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): September 23, 2019

200 West Street, Waltham, MA 02451

(Address of Principal Executive Offices) (Zip Code)

(781) 890-0102

(Registrant’s telephone number, including area code)

N/A

(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:

x                       Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

o                         Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

o                         Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

o                         Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (17 CFR §230.405) or Rule 12b-2 of the Securities Exchange Act of 1934 (17 CFR §240.12b-2).

Emerging growth company x

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

Introductory Comment

Throughout this Current Report on Form 8-K, the terms “we,” “us,” “our”, “Company” and “Proteon” refer to Proteon Therapeutics, Inc., a Delaware corporation.

Item 8.01. Other Events.

On September 23, 2019, Proteon and ArTara Therapeutics, Inc. (“ArTara”) issued a joint press release announcing the combination via merger of Proteon and ArTara. A copy of the press release is attached to this Form 8-K as Exhibit 99.1.

Additionally, Proteon and ArTara will hold a joint conference call and webcast with investors at 8:30 a.m., Eastern Time, on September 24, 2019, during which they will provided supplemental information regarding the proposed merger and related transactions. A copy of the investor presentation for the conference call is attached as Exhibit 99.2 to this Form 8-K.

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SIGNATURE

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.

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