NKTX Nkarta 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): May 14, 2025

Nkarta, Inc.

(Exact name of Registrant as Specified in Its Charter)

Registrant’s Telephone Number, Including Area Code: (925) 407-1049

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. ☒

Item 2.02 Results of Operations and Financial Condition.

On May 14, 2025, Nkarta, Inc. (the “Company”) issued a press release announcing the Company’s financial results for the first quarter ended March 31, 2025. A copy of the Company’s press release is attached hereto as Exhibit 99.1.

The information in Item 2.02 of this Current Report on Form 8-K (including Exhibit 99.1) shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), or otherwise subject to the liabilities of that section, nor shall it be, or be deemed, incorporated by reference in any filings under the Securities Act of 1933, as amended (the “Securities Act”), unless the Company specifically states that the information is to be considered “filed” under the Exchange Act or incorporates it by reference into a filing under the Securities Act or the Exchange Act.

Item 9.01 Financial Statements and Exhibits.

(d) Exhibits.

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.

Exhibit 99.1

Nkarta Reports First Quarter 2025 Financial Results and Corporate Highlights

SOUTH SAN FRANCISCO, Calif., May 14, 2025 -- Nkarta, Inc. (Nasdaq: NKTX), a clinical-stage biopharmaceutical company developing engineered natural killer (NK) cell therapies, today reported financial results for the first quarter and year ended March 31, 2025.

“Our recent restructuring and continued efforts at cost containment have positioned us well to achieve our clinical milestones while ensuring we have cash to support our critical operations into 2029,” said Paul J. Hastings, CEO of Nkarta. “In order to maximize success in our trials, we have incorporated a lymphodepletion regimen utilizing both cyclophosphamide and fludarabine. Similar trials have established this combination, and we believe there is value in producing a comparable dataset while still continuing our cyclophosphamide-only regimen for eligible patients. This approach has potential to provide data on both regimens, which best positions us to advance NKX019 in the clinic and deliver this potential new treatment to patients with B cell-mediated autoimmune diseases. We remain on track to provide our initial clinical update for the Ntrust-1 and Ntrust-2 studies in the second half of 2025.”

Updates for NKX019 clinical programs in Autoimmune Diseases

Anticipated Ntrust clinical trial milestones for 2025

Other Corporate Updates

First Quarter 2025 and Recent Financial Highlights

Financial Guidance

About the Ntrust™ Clinical Trials in Autoimmune Disease

Ntrust-1 (NCT06557265) and Ntrust-2 (NCT06733935) are multi-center, open label, dose escalation clinical trials that build on academic studies of durable, drug-free remissions in patients with autoimmune disease after CD19-targeted cell therapy. Both trials will assess the safety of NKX019 in people living with autoimmune diseases as well as its ability to enable long-term remissions via a “reset” of the immune system through the elimination of pathogenic B cells.

Ntrust-1 is initially enrolling up to 24 patients with lupus nephritis or primary membranous nephropathy. Ntrust-2 is initially enrolling up to 36 patients with systemic sclerosis, idiopathic inflammatory myopathy, or anti-neutrophil cytoplasmic antibody-associated vasculitis.

In both studies, patients receive a three-dose cycle of NKX019 on Days 0, 3, and 7 following lymphodepleting conditioning with either fludarabine and cyclophosphamide or cyclophosphamide alone. Leveraging the engineering of NKX019, no patients in either trial will receive supplemental cytokines or antibody-based therapeutics. This approach is designed to evaluate the single-agent activity of NKX019 and facilitate a more rapid path to regulatory approval. Patients in Ntrust-1 may also receive additional cycles to restore response.

About the Investigator-Sponsored Clinical Trial of NKX019 for Generalized Myasthenia Gravis

The single-arm, open-label Phase 1 investigator-sponsored clinical trial is designed to enroll patients with generalized myasthenia gravis and will evaluate safety and clinical outcomes. Translational and biomarker studies, including autoantibodies, cytokine profiles and pharmacokinetics are planned. Patients receive 3 doses of NKX019 following lymphodepletion. The clinical trial is being co-led by Ali A. Habib, M.D., Clinical Professor of Neurology at the University of California, Irvine, and other investigators.

About the Investigator-Sponsored Clinical Trial of NKX019 for Systemic Lupus Erythematosus

The single-center, single-arm, open-label Phase 1 investigator-sponsored clinical trial (NCT06518668) is designed to enroll up to 6 patients with systemic lupus erythematosus, regardless of renal involvement, and will evaluate safety and clinical outcomes in a potentially different population than Ntrust-1. Translational and biomarker studies, including autoantibodies, cytokine profiles and pharmacokinetics are planned. Patients receive 3 doses of NKX019 following lymphodepletion. The clinical trial is being led by Anca D. Askanase, M.D., M.P.H., Director, Lupus Center at Columbia University Irving Medical Center and the Director of Rheumatology Clinical Trials.

About NKX019

NKX019 is an allogeneic, cryopreserved, off-the-shelf immunotherapy candidate that uses natural killer (NK) cells derived from the peripheral blood of healthy adult donors. It is engineered with a humanized CD19-directed chimeric antigen receptor (CAR) for enhanced cell targeting and a proprietary, membrane-bound form of interleukin-15 (IL-15) for greater persistence and activity without exogenous cytokine support. CD19 is a biomarker for normal B cells as well as those implicated in autoimmune disease and B cell-derived malignancies. Nkarta is evaluating NKX019 in multiple autoimmune conditions.

About Nkarta

Nkarta is a clinical-stage biotechnology company advancing the development of allogeneic, off-the-shelf natural killer (NK) cell therapies for autoimmune diseases. By combining its cell expansion and cryopreservation platform with proprietary cell engineering technologies, Nkarta is building a pipeline of future cell therapies engineered for deep therapeutic activity and intended for broad access in the outpatient treatment setting. For more information, please visit the company’s website at www.nkartatx.com.

Cautionary Note on 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, as amended. Words such as "anticipates," "believes," "expects," "intends," “plans,” “potential,” "projects,” “would” and "future" or similar expressions are intended to identify forward-looking statements. Examples of these forward-looking statements include, but are not limited to, statements concerning Nkarta’s expectations regarding any or all of the following: Nkarta’s position, plans, strategies, and timelines for the continued and future clinical development and commercial potential of NKX019 (including the potential impact of modified lymphodepleting conditioning on our clinical trials, the future availability and disclosure of clinical data and other updates from Nkarta’s clinical trials, and the regulatory pathway for NKX019); the therapeutic potential, accessibility, tolerability, advantages, and safety profile of NK cell therapies, including NKX019 for the treatment of autoimmune diseases, such as lupus, primary membranous nephropathy, systemic lupus erythematosus, systemic sclerosis, myositis, vasculitis, and myasthenia gravis; and Nkarta’s expected cash runway.

Because such statements are subject to risks and uncertainties, actual results may differ materially from those expressed or implied by such forward-looking statements. These risks and uncertainties include, among others: Nkarta’s limited operating history and historical losses; Nkarta’s lack of any products approved for sale and its ability to achieve profitability; the risk that the results of preclinical studies and early-stage clinical trials may not be predictive of future results; Nkarta’s ability to raise additional funding to complete the development and any commercialization of its product candidates; Nkarta’s dependence on the clinical success of NKX019; that Nkarta may be delayed in initiating, enrolling patients in or completing its clinical trials; competition from third parties that are developing products for similar uses; Nkarta’s ability to obtain, maintain and protect its intellectual property; Nkarta’s dependence on third

parties in connection with manufacturing, clinical trials and pre-clinical studies; the complexity of the manufacturing process for CAR NK cell therapies; and the success of Nkarta’s recent (and any future) cost containment measures.

These and other risks and uncertainties are described more fully in Nkarta’s filings with the Securities and Exchange Commission (“SEC”), including the “Risk Factors” section of Nkarta’s Annual Report on Form 10-K for the quarter and year ended December 31, 2024, filed with the SEC on March 26, 2025, and Nkarta’s other documents subsequently filed with or furnished to the SEC. All forward-looking statements contained in this press release speak only as of the date on which they were made. Except to the extent required by law, Nkarta undertakes no obligation to update such statements to reflect events that occur or circumstances that exist after the date on which they were made.

Nkarta, Inc.

Condensed Statements of Operations

(in thousands, except share and per share data)

(Unaudited)

Nkarta, Inc.

Condensed Balance Sheets

(in thousands)

(Unaudited)

Nkarta Media/Investor Contact:

Nadir Mahmood

Nkarta, Inc.

nmahmood@nkartatx.com