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): December 15, 2025

Protara Therapeutics, Inc.

(Exact name of registrant as specified in its charter)

Delaware		001-36694		20-4580525
(State or other jurisdiction of incorporation)		(Commission File No.)		(IRS Employer Identification No.)

345 Park Avenue South

Third Floor

New York, NY

10010

(Address of principal executive offices)

(Zip Code)

Registrant’s telephone number, including area code: (646) 844-0337

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:

☐	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		Trading Symbol(s)		Name of each exchange on which registered
Common Stock, par value $0.001 per share		TARA		The Nasdaq Global 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 ☐

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. ☐

Item 8.01 Other Events.

As previously disclosed, on December 8, 2025, Protara Therapeutics, Inc. (the “Company”) completed a public offering of an aggregate of 13,043,479 shares (the “Firm Shares”) of common stock of the Company, par value $0.001 per share (the “Common Stock”) (the “Offering”). The price to the public in the Offering was $5.75 per Firm Share. In connection with the Offering, the Company also granted the underwriters the option, for 30 days, to purchase up to an additional 1,956,521 shares of Common Stock (the “Option Shares”) at the public offering price, less underwriting discounts and commissions (the “Underwriters’ Option”).

On December 11, 2025, the underwriters notified the Company of their determination to exercise the Underwriters’ Option in full, purchasing the Option Shares, at the public offering price less underwriting discounts and commissions. Closing for the full exercise of the Underwriters’ Option occurred on December 15, 2025.

The Offering, including the full exercise of the Underwriters’ Option, was made pursuant to an effective registration statement on Form S-3 (File No. 333-275290) (the “Registration Statement”) previously filed with the Securities and Exchange Commission on November 3, 2023, and declared effective on November 14, 2023, and related prospectus supplement dated December 4, 2025.

The aggregate gross proceeds to the Company from the Offering, including the full exercise of the Underwriters’ Option, are expected to be approximately $86.3 million, before deducting fees to the underwriters and other estimated offering expenses payable by the Company. The Company intends to use the net proceeds from the Offering, including from the full exercise of the Underwriters’ Option, to fund the clinical development of TARA-002, as well as the development of other clinical programs. The Company may also use the net proceeds from the Offering, including from the full exercise of the Underwriters’ Option, for working capital and other general corporate purposes.

A copy of the opinion and consent of Kirkland & Ellis LLP, counsel to the Company, relating to the validity of the issuance and sale of the Option Shares is filed herewith as Exhibit 5.1 to this Current Report on Form 8-K. Exhibits 5.1 and 23.1 (included in Exhibit 5.1) of this Current Report on Form 8-K are hereby incorporated by reference into the Registration Statement.

Forward-Looking Statements

Statements contained in this Form 8-K regarding matters that are not historical facts are “forward looking statements” within the meaning of the Private Securities Litigation Reform Act of 1995. The Company may, in some cases, use terms such as “predicts,” “believes,” “potential,” “proposed,” “continue,” “designed,” “estimates,” “anticipates,” “expects,” “plans,” “intends,” “may,” “could,” “might,” “will,” “should” or other words or expressions referencing future events, conditions or circumstances that convey uncertainty of future events or outcomes to identify these forward-looking statements. Such forward-looking statements include but are not limited to, statements regarding the Company’s intentions, beliefs, projections, outlook, analyses or current expectations concerning, among other things, the expected use of proceeds from the Offering, including from the full exercise of the Underwriters’ Option. Because such statements are subject to risks and uncertainties, actual results may differ materially from those expressed or implied by such forward-looking statements. Factors that contribute to the uncertain nature of the forward-looking statements include the risks and uncertainties associated with the Company’s business and financial condition in general, including the risks and uncertainties described more fully under the caption “Risk Factors” and elsewhere in the Company’s filings and reports with the United States Securities and Exchange Commission. All forward-looking statements contained in this press release speak only as of the date on which they were made and are based on management’s assumptions and estimates as of such date. The Company undertakes no obligation to update any forward-looking statements, whether as a result of the receipt of new information, the occurrence of future events or otherwise, except as required by law.

Item 9.01 Financial Statements and Exhibits.

(d) Exhibits

Exhibit Number		Exhibit Description
5.1		Opinion of Kirkland & Ellis LLP.
23.1		Consent of Kirkland & Ellis LLP (included in Exhibit 5.1).
104		Cover Page Interactive Data File (embedded within the Inline XBRL document).

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.

Date: December 15, 2025

	Protara Therapeutics, Inc.

	By:	/s/ Patrick Fabbio
		Patrick Fabbio
		Chief Financial Officer

Exhibit 5.1

601 Lexington Avenue

New York, NY 10022

United States

+1 212 446 4800

www.kirkland.com

Facsimile:

+1 212 446 4900

December 15, 2025

Protara Therapeutics, Inc.,

345 Park Avenue South, Third Floor,

New York, New York 10010

Re:

Prospectus Supplement to Registration Statement on Form S-3

Ladies and Gentlemen:

We are issuing this opinion letter in our capacity as special U.S. counsel to Protara Therapeutics, Inc., a Delaware corporation (the “Company”), in connection with the issuance and sale of an aggregate of 1,956,521 shares (the “Shares”) of the Company’s common stock, par value $0.001 per share (the “Common Stock”), pursuant to an underwriting agreement, dated December 4, 2025 (the “Underwriting Agreement”), by and among the Company, J.P. Morgan Securities LLC, TD Securities (USA) LLC and Piper Sandler & Co., as representatives of the several underwriters named in Schedule A thereto. In accordance with the Securities Act of 1933, as amended (the “Securities Act”), and the rules and regulations promulgated thereunder, the Company has prepared and filed with the Securities and Exchange Commission (the “Commission”) on November 3, 2023 a Registration Statement on Form S-3 (Registration No. 333-275290), for the purpose of registering the offering of the Shares under the Securities Act of 1933, as amended (the “Act”), which became effective on November 14, 2023 (the “Registration Statement”), including a base prospectus dated November 14, 2023 and a prospectus supplement dated December 4, 2025 (the “Prospectus Supplement”).

For purposes of the opinions hereinafter expressed, we have examined the Registration Statement, the Prospectus Supplement, the Underwriting Agreement, the corporate and organizational documents of the Company, and originals or copies, certified and otherwise identified to our satisfaction, of such other documents, corporate or limited liability company records, certificates of public officials and other instruments as we have deemed necessary as a basis for the opinions expressed herein. Insofar as the opinions expressed herein involve factual matters, we have relied (without independent factual investigation), to the extent we deemed proper or necessary, upon certificates of, and other communications with, officers and employees of the Company and upon certificates of public officials.

For purposes of this opinion, we have assumed the authenticity of all documents submitted to us as originals, the conformity to the originals of all documents submitted to us as copies and the authenticity of the originals submitted to us as copies. We have also assumed the legal capacity of all natural persons, the genuineness of the signatures of persons signing all documents in connection with which this opinion is rendered, the authority of such persons signing on behalf of the parties thereto and the due authorization, execution and delivery of all documents by the parties thereto. As to any facts material to the opinions expressed herein which we have not independently established or verified, we have relied upon statements and representations of officers and other representatives of the Company and others.

Austin Bay Area Beijing Boston Brussels Chicago Dallas Frankfurt Hong Kong Houston London Los Angeles Miami Munich Paris Philadelphia Riyadh Salt Lake City Shanghai Washington, D.C.

Protara Therapeutics, Inc.,

December 15, 2025

Page 2

Based upon and subject to the assumptions, qualifications and limitations identified in this opinion, we are of the opinion that the Shares have been duly authorized, validly issued, fully paid and nonassessable.

Our advice is limited to the Delaware General Corporation Law. None of the opinions or other advice contained in this letter considers or covers any foreign or state securities (or “blue sky”) laws or regulations.

This opinion is limited to the specific issues addressed herein, and no opinion may be inferred or implied beyond that expressly stated herein. We assume no obligation to revise or supplement this opinion should the General Corporation Law of the State of Delaware be changed by legislative action, judicial decision or otherwise after the date hereof.

This opinion is furnished to you in connection with the filing of the Company’s Current Report on Form 8-K, which is incorporated by reference into the Registration Statement, and in accordance with the requirements of Item 601(b)(5) of Regulation S-K promulgated under the Act, and is not to be used, circulated, quoted or otherwise relied upon or otherwise referred to by any other person for any other purpose. No opinion is expressed herein as to any matter pertaining to the contents of the Registration Statement, other than as to the specific issues addressed herein, and no opinion may be inferred or implied beyond that expressly stated herein.

We hereby consent to the filing of this opinion with the Commission as Exhibit 5.1 to the Company’s Current Report on Form 8-K and its incorporation into the Registration Statement. We also consent to the reference to our firm under the heading “Validity of Securities” in the Prospectus Supplement constituting a part of the Registration Statement. In giving this consent, we do not thereby admit that we are in the category of persons whose consent is required under Section 7 of the Act or the rules and regulations of the Commission.

	Yours very truly,

	/s/ KIRKLAND & ELLIS LLP

	KIRKLAND & ELLIS LLP