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 3, 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 7.01 Regulation FD Disclosure.

On December 3, 2025, Protara Therapeutics, Inc. (the “Company” or “Protara”) posted an investor presentation (the “Investor Presentation”) to the “Investors—Events and Presentations” section of the Company’s website and posted a press release (the “Press Release”) to the “Investors—News—Press Releases” section of the Company’s website. The Investor Presentation and Press Release will be used in connection with a conference call and webcast on December 3, 2025, at 8:30 a.m. ET, to announce updated interim data from the ongoing Phase 2 open-label ADVANCED-2 Trial of TARA-002 in patients with carcinoma in situ or CIS (± Ta/T1) non-muscle invasive bladder cancer (“NMIBC”).

Copies of the Investor Presentation and Press Release are attached as Exhibit 99.1 and Exhibit 99.2, respectively. The information contained in Item 7.01 of this Current Report on Form 8-K, including Exhibit 99.1 and Exhibit 99.2, is being furnished and shall not be deemed to be “filed” for the purposes of Section 18 of the Exchange Act of 1934, as amended (the “Exchange Act”), or otherwise subject to the liabilities of that section and shall not be incorporated by reference in any filing under the Securities Act of 1933, as amended, or the Exchange Act, except as shall be expressly set forth by specific reference in such filing.

Item 8.01 Other Events.

Updated Interim Results

On December 4, 2025, the Company presented updated interim data from its ongoing Phase 2 open-label ADVANCED-2 Trial of TARA-002 in patients with carcinoma in situ or CIS (± Ta/T1) NMIBC at a poster session at the 2025 Annual Meeting of the Society of Urologic Oncology (SUO) Conference, reporting positive results that continue to support TARA-002’s potential as a mainstay in the NMIBC treatment landscape and demonstrating meaningful and durable activity in Bacillus Calmette-Guérin (“BCG”)-Naïve NMIBC patients. A copy of the poster, which has been published to the “Investors—Events and Presentations” section of the Company’s website, is filed as Exhibit 99.3 to this Current Report on Form 8-K and is incorporated herein by reference.

The dataset includes 31 BCG-Naïve patients who received at least 1 dose of TARA-002; 29 patients completed at least one response assessment and were evaluable for efficacy as of a November 7, 2025 data cutoff. Patients received an induction course of six weekly intravesical instillations of TARA-002, followed by a maintenance course of three weekly instillations every three months. Re-induction was permitted for eligible patients with residual CIS and/or recurrent high-grade Ta disease. Complete response (“CR”) rates at the six months and 12 months landmark time points include all participants who were either evaluable at that time point or had experienced disease progression or treatment failure prior to the scheduled visit. The CR rate at any time was 72% (21/29). The CR rate was 69% (18/26) at six months and 50% (7/14) at 12 months. Among initial responders, 88% (14/16) maintained their response through six months and 100% (3/3) through 12 months. Re-induction therapy successfully salvaged most initial non-responders, resulting in high conversion rates and durable responses: 80% (4/5) of re-induced patients converted to a CR at 6 months, and 100% (4/4) of those responders maintained their CR at 12 months.

The majority of treatment-related adverse events (“TRAEs”) were Grade 1 and transient with no Grade 3 or greater TRAEs as assessed by study investigators. No patients discontinued treatment due to TRAEs. The most commonly occurring TRAEs were dysuria (13%), fatigue (13%), and hematuria (6%).

Regulatory Update

The Company remains in ongoing dialogue with the U.S. Food and Drug Administration (“FDA”) on an expansion of the agreed upon registrational path forward for TARA-002 beyond the BCG-Unresponsive NMIBC patient population. The FDA has provided written feedback supporting a registrational design for a controlled trial in BCG-Naïve patients (who have never been exposed and those who have not received BCG within the last 24 months and are ineligible to receive BCG or contraindicated, cannot tolerate BCG, do not have access to BCG, or refuse BCG). The FDA has agreed that BCG is not required as a comparator and that intravesical chemotherapy is an acceptable comparator to TARA-002 in BCG-Naïve patients. The FDA also is aligned with the primary endpoint of the trial as the CR rate at month 6 with duration of response as a key secondary endpoint. The Company has engaged the FDA to determine how to include BCG-Exposed patients in its clinical trials of TARA-002, for whom no FDA-approved treatments are available and who have limited options to access investigational treatment through clinical trials.

Forward-Looking Statements

Statements contained herein regarding matters that are not historical facts are “forward looking statements” within the meaning of the Private Securities Litigation Reform Act of 1995. Protara 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 Protara’s intentions, beliefs, projections, outlook, analyses or current expectations concerning, among other things: Protara’s business strategy, including its development plans for its product candidates and plans regarding the timing or outcome of existing or future clinical trials (including the timing of any particular phases of such trials and the timing of the announcement of any data produced during such trials or phases thereof; statements related to expectations regarding interactions with the U.S. Food and Drug Administration (FDA); Protara’s financial position; statements regarding the anticipated safety or efficacy of Protara’s product candidates; and Protara’s outlook for the remainder of the year and future periods. 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: risks that Protara’s financial guidance may not be as expected, as well as risks and uncertainties associated with: Protara’s development programs, including the initiation and completion of non-clinical studies and clinical trials and the timing of required filings with the FDA and other regulatory agencies; general market conditions; changes in the competitive landscape; changes in Protara’s strategic and commercial plans; Protara’s ability to obtain sufficient financing to fund its strategic plans and commercialization efforts; having to use cash in ways or on timing other than expected; the impact of market volatility on cash reserves; failure to attract and retain management and key personnel; the impact of general U.S. and foreign, economic, industry, market, regulatory, political or public health conditions; and the risks and uncertainties associated with Protara’s business and financial condition in general, including the risks and uncertainties described more fully under the caption “Risk Factors” and elsewhere in Protara’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. Protara 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
99.1		Investor Presentation, dated December 3, 2025.
99.2		Press Release, dated December 3, 2025.
99.3		Poster Presentation, dated December 4, 2025.
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 3, 2025

	Protara Therapeutics, Inc.

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

Exhibit 99.1

Interim Data Presentation From the ADVANCED - 2 Trial of TARA - 002 in BCG - Naïve NMIBC Patients Society Of Urologic Oncology Annual Meeting December 2025

2 Statements contained in this presentation regarding matters that are not historical facts are "forward looking statements" wi thi n the meaning of the Private Securities Litigation Reform Act of 1995. Protara 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 outco mes to identify these forward - looking statements. Such forward - looking statements include but are not limited to, statements regarding Protara’s intentions, beliefs, projections, outlook, analyses or current expectations concerning, among other things: Protara’s business strategy, inc luding its development plans for its product candidates and plans regarding the timing or outcome of existing or future clinical trials (in cluding the timing of any particular phases of such trials and the timing of the announcement of any data produced during such trials or pha ses thereof); statements related to expectations regarding interactions with the U.S. Food and Drug Administration (FDA); Protara’s financi al position; statements regarding the anticipated safety or efficacy of Protara’s product candidates; and Protara’s outlook for the remain der of the year and future periods. Because such statements are subject to risks and uncertainties, actual results may differ materially from th ose expressed or implied by such forward - looking statements. Factors that contribute to the uncertain nature of the forward - looking statements include: risks that Protara’s financial guidance may not be as expected, as well as risks and uncertainties associated with: Pro tara’s development programs, including the initiation and completion of non - clinical studies and clinical trials and the timing of requ ired filings with the FDA and other regulatory agencies; general market conditions; changes in the competitive landscape; changes in Prota ra’ s strategic and commercial plans; Protara’s ability to obtain sufficient financing to fund its strategic plans and commercialization effo rts ; having to use cash in ways or on timing other than expected; the impact of market volatility on cash reserves; failure to attract and retai n m anagement and key personnel; the impact of generalU.S.and foreign, economic, industry, market, regulatory, political or public health condi tio ns; and the risks and uncertainties associated with Protara’s business and financial condition in general, including the risks and uncert ain ties described more fully under the caption “Risk Factors” and elsewhere in Protara's filings and reports with theUnited States Securities a nd Exchange Commission. All forward - looking statements contained in this presentation speak only as of the date on which they were made and are based on management's assumptions and estimates as of such date. Protara 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 re qui red by law. © 2025 Protara Therapeutics. All Rights Reserved – Do Not Copy or Distribute. | Forward Looking Statements

Jesse Shefferman Co - founder, Director, Chief Executive Officer Jacqueline Zummo, PhD Co - founder, Senior Vice President, Chief Scientific Operations Officer Neal Shore, MD Medical Director, Carolina Urologic Research Center Introduction and TARA - 002 Overview Jesse Shefferman Review of Updated Data Leonardo Viana Nicacio, MD KOL Discussion Neal Shore, MD Regulatory Updates Jacqueline Zummo, PhD Closing Remarks Jesse Shefferman Q&A All © 2025 Protara Therapeutics. All Rights Reserved – Do Not Copy or Distribute. | 3 Leonardo Viana Nicacio, MD Chief Medical Officer Agenda

Key Clinical and Regulatory Updates 4 TARA - 002 in NMIBC 1. Updated interim data from the Phase 2 ADVANCED - 2 trial of TARA - 002 in BCG - Naïve NMIBC patients • TARA - 002 demonstrated 72% CR rate at any time, 69% 6 - month landmark CR rate and 50% 12 - month landmark CR rate 1 • Favorable safety and tolerability profile observed with no Grade 3 or greater TRAEs 2. TARA - 002 has anticipated low burden on physicians & patients • No additional administration procedures or safety protocols required to date • Fast administration typically performed by nurse 3. Registrational BCG - Unresponsive cohort progressing • Remain on track to report interim results from approximately 25 six - month evaluable BCG - Unresponsive patients in Q1 2026 • Expect to complete enrollment of the BCG - Unresponsive cohort in 2H 2026 TARA - 002 for Non - Muscle Invasive Bladder Cancer (NMIBC) & Lymphatic Malformations (LMs) © 2025 Protara Therapeutics. All Rights Reserved – Do Not Copy or Distribute. | 1 Referencing data from November 7, 2025, presented at SUO conference

*Currently in pre - clinical studies to define dosing and, once protocol is confirmed, expect to initiate P2 trial cohort. **IV Choline granted Orphan Drug Designations by the U.S. FDA for the prevention and/or treatment of choline deficiency in pa ti ents on long - term PN and Fast Track Designation as a source of choline when oral or enteral nutrition is not possible, insuffici ent, or contraindicated. ***TARA - 002 granted Rare Pediatric Disease Designation by the U.S. FDA and Orphan Drug Designation by the European Commission f or the treatment of LMs. † Trial also includes BCG - Exposed patients. 1 Subject to regulatory clearance 2 Potential expansion opportunity for NMIBC program © 2025 Protara Therapeutics. All Rights Reserved – Do Not Copy or Distribute. | 5 Indication Pre - Clinical Phase 1 Phase 2 Phase 3 Status ONCOLOGY TARA - 002 ADV - 2 CIS + Ta/T1 NMIBC BCG - Naïve † Fully enrolled CIS + Ta/T1 NMIBC BCG - Unresponsive Full enrollment expected 2H’26 TARA - 002 CIS + Ta/T1 NMIBC BCG - Naïve 1 TARA - 002 NMIBC Expansion HR NMIBC Ta / T1 PoC 2 TARA - 002 Systemic Administration HR NMIBC 2 RARE DISEASES IV CHOLINE Choline for parenteral support (PS) patients** Interim data expected 2H’26 TARA - 002 Lymphatic Malformations (LMs)*** Regulatory feedback expected 1H’26 Full enrollment expected 2H’26 ADVANCED - 2 (Cohort A) ADVANCED - 2 (Cohort B) BCG - Naïve RCT ADVANCED - 2 (Cohort E) ADVANCED - 2 (Cohort C,D)* Indicates potential clinical programs yet to be initiated STARBORN - 1 THRIVE - 3 Robust Late - Stage Pipeline

TARA - 002 Lyophilized, Inactivated Group A Streptococcus pyogenes

TARA - 002 ignites both innate and adaptive immunity through dual TLR2/NOD2 activation, driving potent local anti - tumor / cystic responses via fully inactivated bacteria (1)(2)(3) © 2025 Protara Therapeutics. All Rights Reserved – Do Not Copy or Distribute. | 7 1 Fujimoto T., et al. J Immunol. 1997: 5619; 2 Ryoma Y, et al. Anticancer Res. 2004; 3295 - 3298; 3 Zhao H, et al. Microbiol. Immunol. 1994; 183 - 190 TARA - 002: A Unique TLR2/NOD2 Agonist Derived From Streptococcus Pyogenes That Brings A New Immunologic Mechanism to NMIBC Beyond BCG

Cytokines BCG TARA - 002 IFN - γ --- + TNF - α + +++ IL - 12p70 = + IL - 8 = - IL - 6 + + IL - 1β +++ +++ IL - 10 = + IL - 4 + + IL - 13 = = IL - 2 -- -- TARA - 002 DEMONSTRATES DIFFERENTIATED PROFILE TO BCG © 2025 Protara Therapeutics. All Rights Reserved – Do Not Copy or Distribute. | 8 = : No change + : 2 - 5 fold upregulation +++ : ≥ 15 - fold upregulation - : 2 - 5 fold downregulation -- : 5 - 14 - fold downregulation --- : ≥ 15 - fold downregulation TARA - 002 treatment promotes differential pro - inflammatory TH1 - type cytokines than BCG in co - culture 1 TARA - 002 Potent Immune Activation with a Distinct Cytokine Signature • Distinct cytokine profile marked by strong TH1 activation (↑ IFN - γ, TNF - α, IL - 12p70), defining an immune signature different from BCG • Selectively downregulates IL - 8, a cytokine linked to tumor recurrence and progression in NMIBC 1 Internal pre - clinical data.

Abbreviations: CR = complete response; CIS = carcinoma in situ *Aligned with the FDA’s 2024 BCG Unresponsive NMIBC: Developing Drugs and Biologics for Treatment Guidance for Industry. **Enrollment complete †Residual CIS and/or recurrence of HGTa; ^3 weekly instillations every 3 months through month 18 and then at month 24 Primary endpoint of high - grade complete response (CR) at any time until 6 months; Key secondary endpoint of 12 - month DOR TARA - 002 IN NMIBC: ADVANCED - 2 CLINICAL TRIAL DESIGN 10 DAY 1 MONTH 3 MONTH 6 MONTH 24 MONTH 60 REGISTRATIONAL DESIGN*: BCG - Unresponsive (CIS ± Ta/T1) BCG Naïve (CIS ± Ta/T1) Induction (N=100) 6 weekly instillations Induction (N=31**) 6 weekly instillations CR, Maintenance (months 3 - 24) 3 weekly instillations every 3 months through month 18 and then at month 24 Follow - up Follow - up CR, Maintenance (months 3 - 24) 3 weekly instillations every 3 months through month 18 and then at month 24 Maintenance (months 6 - 24) 3 weekly instillations every 3 months^ Maintenance (months 6 - 24) 3 weekly instillations every 3 months^ Re - Induction (if eligible † ) 6 weekly instillations Re - Induction (if eligible † ) 6 weekly instillations Follow - up Follow - up © 2025 Protara Therapeutics. All Rights Reserved – Do Not Copy or Distribute. | CT.gov identifier: NCT05951179

TARA - 002 Monotherapy Demonstrates 69% CR at 6 months and 50% CR at 12 Months in BCG - Naïve Participants 11 Abbreviations: CR = complete response High - grade CR is based on central pathology. Notes: Evaluable participants include those who had at least one dose of study drug before the response assessment time point and completed at least one response assessment; CR rates at each landmark time point include all participants who were either evaluable at that time point or had experienced disease progression or treatment failure prior to the scheduled visit ^ Participants enrolled under an earlier protocol version with 6 - month follow - up; therefore, they are not included in CR analyse s from Month 9 onward. Data cutoff: 7 November 2025 High - grade CR rate at any time (%) Landmark High - grade CR rate (%) Month 6 69.2 (18 of 26) Month 12 50.0 (7 of 14) © 2025 Protara Therapeutics. All Rights Reserved – Do Not Copy or Distribute. | Source: Internal clinical data. 0 20 40 60 80 100 N = 29 72.4% 21 of 29

N = 31 Any Grade Grade 1 Grade 2 Grade 3 Grade 4/5 TRAEs, n (%) 8 (26) 8 (26) 1 (3) 0 0 TRAEs ≥5%, n (%) 17 (55) 15 (48) 2 (6) 0 0 Dysuria 4 (13) 4 (13) 0 0 0 Fatigue 4 (13) 3 (10) 1 (3) 0 0 Haematuria 2 (6) 2 (6) 0 0 0 SAEs, n (%) 4 (13) 0 1 (3) 4 (13) 0 Related SAEs, n (%) 0 0 0 0 0 TRAEs leading to Study Drug Withdrawal, n (%) 0 0 0 0 0 TRAE = treatment related adverse event; SAE = serious adverse event Severity of adverse event is based on NCI - CTCAE Version 5.0 or later. Data cutoff: 7 November 2025 TARA - 002 demonstrated a favorable safety and tolerability profile with no Grade 3 or greater TRAEs in BCG - naïve participants 12 © 2025 Protara Therapeutics. All Rights Reserved – Do Not Copy or Distribute. |

13 TARA - 002 Target Product Profile Fits at the Intersection that NMIBC Patients and Urologists Prioritize © 2025 Protara Therapeutics. All Rights Reserved – Do Not Copy or Distribute. | Safety & Tolerability Efficacy and Durability Ease - of - Use • Mild, self - limited local AEs • Predictable, well - characterized safety profile • Robust single agent activity • Competitive CR rates • Encouraging durability • Simple office - based IVe instillation • No viral handling, refrigeration or reconstitution complexity • Fits the urology workflows TARA - 002 IVe=intravesical

KOL DISCUSSION Neal Shore, MD Medical Director, Carolina Urologic Research Center

FDA Aligned with Us On Our Proposed BCG - Naïve Definition and Design 15 Reached alignment on Under discussion No BCG in comparator arm Definition of BCG - Naïve study population (never been exposed and those who have not received BCG within the last 24 - months and who are ineligible to receive BCG or contraindicated, cannot tolerate BCG, do not have access to BCG, or refuse BCG) CR rate at Month 6 and DOR as primary and key secondary endpoints, respectively Powered for superiority compared to intravesical chemotherapy Ongoing discussions of TARA - 002 in the BCG exposed population Finalizing approach to include broadest patient population © 2025 Protara Therapeutics. All Rights Reserved – Do Not Copy or Distribute. |

CLOSING REMARKS 16

Q&A Jesse Shefferman Co - founder, Director, Chief Executive Officer Jacqueline Zummo, PhD Co - founder, Senior Vice President, Chief Scientific Operations Officer Neal Shore, MD Medical Director, Carolina Urologic Research Center © 2025 Protara Therapeutics. All Rights Reserved – Do Not Copy or Distribute. | 17 Leonardo Viana Nicacio, MD Chief Medical Officer

THANK YOU

APPENDIX

Demographics Cohort A N = 31 Baseline Characteristics Cohort A N = 31 Age (years) ECOG PS, n (%) Mean (SD) 70.4 (10.29) 0 26/31 (83.9) Median (Min, Max) 71 (45, 89) 1 4/31 (12.9) Sex, n (%) 2 1/31 (3.2) Male 25/31 (80.6) 3 0 Female 6/31 (19.4) 4 0 Race, n (%) 5 0 American Indian or Alaska Native 0 Diagnosis, n (%) Asian 0 CIS (only) 18/31 (58.1) Black or African American 1/31 (3.2) CIS + Ta 9/31 (29.0) Native Hawaiian or Pacific Islander 0 CIS + T1 4/31 (12.9) White 29/31 (93.5) BCG Exposure, n (%) Other 0 Never exposed 24/31 (77.4) Not Reported 1/31 (3.2) BCG exposed >24 months 7/31 (22.6) Ethnicity, n (%) Hispanic 3/31 (9.7) Non - Hispanic 28/31 (90.3) Demographics and Baseline Characteristics in BCG - Naïve Participants Data cutoff: 7 November 2025 © 2025 Protara Therapeutics. All Rights Reserved – Do Not Copy or Distribute

Exhibit 99.2

Protara Therapeutics Announces Updated Interim Data from Phase 2 ADVANCED-2 Trial of TARA-002 in BCG-Naïve NMIBC Patients

●

TARA-002 demonstrates 72% complete response rate at any time in BCG-Naïve patients

●

TARA-002 demonstrates a 69% complete response rate at the 6-month landmark and a 50% complete response rate at the 12-month landmark in BCG-Naïve patients

●

Favorable safety and tolerability profile observed with no Grade 3 or greater treatment-related adverse events reported

●

Company obtained written feedback from FDA on registrational path forward for TARA-002 in BCG-Naïve patients

●

Company remains on track to report interim results from approximately 25 six-month evaluable BCG-Unresponsive patients in the registrational cohort of the ADVANCED-2 trial in Q1 2026

●

Company expects to complete enrollment of the BCG-Unresponsive registrational cohort of the ADVANCED-2 trial in 2H 2026

●

Company to host conference call and webcast today at 8:30 a.m. ET

NEW YORK, Dec. 3, 2025 -- Protara Therapeutics, Inc. (Nasdaq: TARA), a clinical-stage company developing transformative therapies for the treatment of cancer and rare diseases, today announced updated interim data from the ongoing Phase 2 open-label ADVANCED-2 trial of TARA-002 in patients with carcinoma in situ or CIS (± Ta/T1) non-muscle invasive bladder cancer (NMIBC). These results in Bacillus Calmette-Guérin (BCG)-Naïve NMIBC patients will be featured during a poster session at the 26th Annual Meeting of the Society of Urologic Oncology (SUO) in Phoenix, Arizona.

“These positive results continue to support TARA-002’s potential in the NMIBC treatment landscape, and we look forward to finalizing a regulatory pathway for TARA-002 in BCG-Naïve patients,” said Jesse Shefferman, Chief Executive Officer of Protara Therapeutics. “We remain on track to provide an update on the registrational BCG-Unresponsive patient cohort in the ADVANCED-2 trial in the first quarter of 2026 and expect to complete enrollment of this cohort in the second half of 2026.”

“These encouraging TARA-002 results demonstrate meaningful and durable activity in BCG-Naïve NMIBC patients,” said Mark Tyson, M.D., MPH, Vice Chair for Research and a Professor in the Department of Urology with the Mayo Clinic in Phoenix, Arizona, and ADVANCED-2 study investigator. “The clinically meaningful response rates at six and 12 months, coupled with a favorable safety and tolerability profile and simple administration that is even more streamlined than BCG, make TARA-002 a compelling potential treatment option in the BCG-Naïve setting.”

Updated Interim Results

●

The CR rate at any time was 72% (21/29).

●

The CR rate was 69% (18/26) at six months and 50% (7/14) at 12 months.

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Among initial responders, 88% (14/16) maintained their response through six months and 100% (3/3) through 12 months.

●

Re-induction therapy successfully salvaged most initial non-responders, resulting in high conversion rates and durable responses: 80% (4/5) of re-induced patients converted to a CR at 6 months, and 100% (4/4) of those responders maintained their CR at 12 months.

Safety and Tolerability

The majority of treatment-related adverse events (TRAEs) were Grade 1 and transient with no Grade 3 or greater TRAEs as assessed by study investigators. No patients discontinued treatment due to TRAEs. The most commonly occurring TRAEs were dysuria (13%), fatigue (13%), and hematuria (6%).

Regulatory Update

The Company remains in ongoing dialogue with the U.S. Food and Drug Administration (FDA) on an expansion of the agreed upon registrational path forward for TARA-002 beyond the BCG-Unresponsive NMIBC patient population. The FDA has provided written feedback supporting a registrational design for a controlled trial in BCG-Naïve patients (who have never been exposed and those who have not received BCG within the last 24 months and are ineligible to receive BCG or contraindicated, cannot tolerate BCG, do not have access to BCG, or refuse BCG). The FDA has agreed that BCG is not required as a comparator and that intravesical chemotherapy is an acceptable comparator to TARA-002 in BCG-Naïve patients. The FDA also is aligned with the primary endpoint of the trial as the CR rate at month 6 with duration of response as a key secondary endpoint. The Company has engaged the FDA to determine how to include BCG-Exposed patients in its clinical trials of TARA-002, for whom no FDA-approved treatments are available and who have limited options to access investigational treatment through clinical trials.

About ADVANCED-2

ADVANCED-2 (NCT05951179) is a Phase 2 open-label trial assessing intravesical TARA-002 in NMIBC patients with carcinoma in situ or CIS (± Ta/T1) who are Bacillus Calmette-Guérin (BCG)-Unresponsive (Cohort B N=75-100) or BCG-Naïve (Cohort A N=31). Trial subjects received an induction course, with or without a reinduction, of six weekly intravesical instillations of TARA-002, followed by a maintenance course of three weekly instillations every three months.

The Company remains on track to report interim results from approximately 25 six-month evaluable NMIBC patients from ADVANCED-2 with carcinoma in situ or CIS (± Ta/T1) who are BCG-Unresponsive in the first quarter of 2026 and expects to complete enrollment in this cohort in the second half of 2026.

Conference Call and Webcast

Protara will host a conference call and webcast today at 8:30 am ET to review the data reported this morning. The live event and accompanying slides can be accessed by visiting https://protara-therapeutics-suo-update-call.open-exchange.net/registration, or via the Events and Presentations section of the Company’s website: https://ir.protaratx.com. A replay of the webcast will be archived for a limited time following the event.

About TARA-002

TARA-002 is an investigational cell therapy in development for the treatment of NMIBC and of LMs, for which it has been granted Rare Pediatric Disease Designation by the U.S. Food and Drug Administration. TARA-002 was developed from the same master cell bank of genetically distinct group A Streptococcus pyogenes as OK-432, a broad immunopotentiator marketed as Picibanil® in Japan by Chugai Pharmaceutical Co., Ltd. Protara has successfully shown manufacturing comparability between TARA-002 and OK-432.

TARA-002 is a first-in-class TLR2/NOD2 agonist and novel immunopotentiator derived from inactivated Streptococcus pyogenes with a mechanism of action that includes the activation of innate and adaptive immune pathways within the bladder wall. When TARA-002 is administered, it is hypothesized that innate and adaptive immune cells within the cyst or tumor are activated and produce a pro-inflammatory response with release of cytokines such as tumor necrosis factor (TNF)-alpha, interferon (IFN)-gamma IL-6, IL-10, IL-12. TARA-002 also directly kills tumor cells and triggers a host immune response by inducing immunogenic cell death, which further enhances the antitumor immune response.

About Non-Muscle Invasive Bladder Cancer (NMIBC)

Bladder cancer is the sixth most common cancer in the United States, with NMIBC representing approximately 80% of bladder cancer diagnoses. Approximately 65,000 patients are diagnosed with NMIBC in the United States each year. NMIBC is cancer found in the tissue that lines the inner surface of the bladder that has not spread into the bladder muscle

About Protara Therapeutics, Inc.

Protara is a clinical-stage biotechnology company committed to advancing transformative therapies for people with cancer and rare diseases. Protara’s portfolio includes its lead candidate, TARA-002, an investigational cell-based therapy in development for the treatment of non-muscle invasive bladder cancer (NMIBC) and lymphatic malformations (LMs). The Company is evaluating TARA-002 in an ongoing Phase 2 trial in NMIBC patients with carcinoma in situ (CIS) who are unresponsive or naïve to treatment with Bacillus Calmette-Guérin, as well as a Phase 2 trial in pediatric patients with LMs. Additionally, Protara is developing IV Choline Chloride, an investigational phospholipid substrate replacement for patients on parenteral nutrition who are otherwise unable to meet their choline needs via oral or enteral routes. For more information, visit www.protaratx.com.

Forward-Looking Statements

Statements contained in this press release regarding matters that are not historical facts are “forward looking statements” within the meaning of the Private Securities Litigation Reform Act of 1995. Protara 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 Protara’s intentions, beliefs, projections, outlook, analyses or current expectations concerning, among other things: Protara’s business strategy, including its development plans for its product candidates and plans regarding the timing or outcome of existing or future clinical trials (including the timing of any particular phases of such trials and the timing of the announcement of any data produced during such trials or phases thereof); statements related to expectations regarding interactions with the U.S. Food and Drug Administration (FDA); Protara’s financial position; statements regarding the anticipated safety or efficacy of Protara’s product candidates; and Protara’s outlook for the remainder of the year and future periods. 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: risks that Protara’s financial guidance may not be as expected, as well as risks and uncertainties associated with: Protara’s development programs, including the initiation and completion of non-clinical studies and clinical trials and the timing of required filings with the FDA and other regulatory agencies; general market conditions; changes in the competitive landscape; changes in Protara’s strategic and commercial plans; Protara’s ability to obtain sufficient financing to fund its strategic plans and commercialization efforts; having to use cash in ways or on timing other than expected; the impact of market volatility on cash reserves; failure to attract and retain management and key personnel; the impact of general U.S. and foreign, economic, industry, market, regulatory, political or public health conditions; and the risks and uncertainties associated with Protara’s business and financial condition in general, including the risks and uncertainties described more fully under the caption “Risk Factors” and elsewhere in Protara’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. Protara 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.

Company Contact:

Justine O’Malley

Protara Therapeutics

[email protected]

646-817-2836

Exhibit 99.3

ADVANCED - 2: Preliminary Efficacy and Safety Data in BCG - naïve Participants with High - grade Non - muscle Invasive Bladder Cancer Mark Tyson 1 , Gautam Jayram 2 , Myroslava Doronina 3,4 , Eugene Kramolowsky 5 , Brian Mazzarella 6 , Alexander Sankin 7 , Jacqueline Zummo 8 , Carla Beckham 8 , Eppie Brown 8 , Khushboo Belani 8 , Claire Middleton 8 , Andrea DiFiglia 8 , Brian Desch 8 , Chen Ǫuin Lam 9 , Neal Shore 10 , Zoreslava Lysak 3 , Evgeny Levenko 3 1 Mayo Clinic, Phoenix, AZ, USA, 2 Urology Associates P.C., Nashville, TN, USA, 3 Arensia Exploratory Medicine LLC, Kyiv, Ukraine, 4 Shupyk National Healthcare University of Ukraine, Kyiv, Ukraine, 5 Virginia Urology, Richmond, VA, USA, 6 Urology Austin, Austin, TX, USA, 7 Montefiore Medical Center, Bronx, NY, USA, 8 Protara Therapeutics, Inc., New York, NY, USA, 9 Pharmapace Inc., San Diego, CA, USA, 10 Carolina Urologic Research Center, Myrtle Beach, SC, USA BACKGROUND • There continues to be a significant unmet need for safe, effective, and bladder - sparing treatment options for patients with NMIBC, and this need is more pronounced in patients who are unable to access or receive BCG • TARA - 002 is a first - in - class TLR2/NOD2 agonist and novel immunopotentiator derived from inactivated Streptococcus pyogenes with a mechanism of action that includes the activation of innate and adaptive immune pathways within the bladder wall • TARA - 002 has shown safety and efficacy in patients with high - grade NMIBC in a BCG - unresponsive cohort and ease of use for providers METHODS • ADVANCED - 2 (NCT05951179) – Cohort A is a Phase 2, ongoing, open - label study of intravesical TARA - 002 in adults ≥ 18 years with high - grade NMIBC with CIS “ Ta/T1 who have active disease and are BCG - naïve (defined as patients who have never been exposed and those who have not received intravesical BCG for at least 24 months) • Endpoints: — Primary: High - grade complete response (CR) at any time according to central pathology — Key secondary: Duration of response (12 months) • The data cutoff date is 7 November 2025 • Enrollment in this cohort is complete ADVANCED - 2 COHORT A (BCG - NAÏVE) STUDY SCHEMA Abbreviations: BCG = Bacillus Calmette - Guérin; CR = complete response; CIS = carcinoma in situ; HGTa = high grade Ta tumor; T1 = carcinoma invading the lamina propria; Ta = non - invasive papillary carcinoma. *Eligible for re - induction: Residual CIS and/or recurrence of HGTa RESULTS TARA - 002 MONOTHERAPY DEMONSTRATES STRONG EFFICACY AND DURABILITY IN BCG - NAÏVE PARTICIPANTS Abbreviations: CR = complete response Note: Evaluable participants include those who had at least one dose of study drug before the response assessment time point and completed at least one response assessment. CR rates at each landmark time point include all participants who were either evaluable at that time point or had experienced disease progression or treatment failure prior to the scheduled visit. Participants who have not yet completed the visit time point were not included. • This study includes 31 BCG - naïve participants with a median age of 71.0 years (Min: 45 years; Max: 89 years) and the majority of participants are male (80.6%, 25/31) and White (93.5%, 29/31) • The rate of high - grade CR at any time was 72.4% (21 of 29) • The rate of high - grade CR was 69.2% (18 of 26) at Month 6 and 50.0% (7 of 14) at Month 12 • Among initial responders, 87.5% (14 of 16) maintained their response through Month 6 and 100% (3 of 3) through Month 12 • Among the initial non - responders who underwent re - induction, 80% (4 of 5) converted to a CR by Month 6; all responders maintained CR through Month 12 (4 of 4) • The majority of TRAEs were Grade 1 and transient; commonly occurring TRAEs included fatigue, dysuria and hematuria • No participants experienced ≥ Grade 3 TRAEs, related SAEs or TRAEs leading to withdrawal CONCLUSIONS • In BCG - naïve high - grade NMIBC participants, TARA - 002 demonstrated a high rate of complete response with a substantial proportion maintaining a durable response at 1 year • Re - induction therapy successfully salvaged most initial non - responders, resulting in high conversion rates and durable responses • TARA - 002 was well tolerated; common urinary TEAEs reflect urinary tract instrumentation effects and systemic TEAEs were mild and easily managed • These findings support continued investigation of TARA - 002 in BCG - naïve HG - NMIBC TARA - 002 MONOTHERAPY DEMONSTRATES 50% HIGH - GRADE COMPLETE RESPONSE AT 12 MONTHS IN BCG - NAÏVE PARTICIPANTS ^Participants enrolled under an earlier protocol version with 6 - month follow - up; therefore, they are not included in CR analyses from Month 9 onward TARA - 002 SHOWS A FAVORABLE SAFETY PROFILE WITH NO TRAEs ≥ GRADE 3, NO RELATED SAEs OR TRAEs LEADING TO WITHDRAWAL IN BCG - NAÏVE PARTICIPANTS Grade 4/5 Grade 3 Grade 2 Grade 1 Any Grade N = 31 0 0 1 (3) 8 (26) 8 (26) TRAEs, n (%) 0 4 (13) 1 (3) 0 4 (13) SAEs, n (%) 0 0 0 0 0 Related SAEs, n (%) 0 0 0 0 0 TRAEs leading to Study Drug Withdrawal, n (%) Abbreviations: SAE = serious adverse event; TRAE = treatment related adverse event Note: Severity of adverse event is based on NCI - CTCAE Version 5.0 or after. Day 1 Month 3 Month 6 Month 24 Month 60 BCG - naïve (CIS “ Ta/T1) Induction (N=31) 6 weekly instillations CR, Maintenance (months 3 - 24) 3 weekly instillations every 3 months to M18, then again at M24 Follow - up Follow - up Re - induction (if eligible*) 6 weekly instillations Maintenance (months 6 - 24) 3 weekly instillations every 3 months to M18, then again at M24 Screenin g 0 3 6 9 12 Months 5 10 15 20 25 Complete Response Recurrence/Non - Response Eligible for Reinduction Treatment Ongoing Study Completed Treatment/Study Discontinued ^ ^ ^ ^ 72.4% (21 of 29) High - grade CR Rate at any time (%) Landmark Month 6 Month 12 High - grade CR Rate (%) 69.2 (18 of 26) 50.0 (7 of 14) 100 80 60 40 20 0 N = 29 Contact: [email protected] DISCLOSURES This study was funded by Protara Therapeutics, Inc. ACKNOWLEDGEMENTS Digital and print editorial services powered by Princeton Biomedical Comm., LLC. < Scan here for ePoster Presented at SUO 26th Annual Meeting. December 2 – 5, 2025, Phoenix, AZ Poster No: 149