Organization and Description of Business	3 Months Ended
Mar. 31, 2024
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization and Description of Business	1. Organization and Description of Business Description of the Business Nkarta, Inc. ("Nkarta" or the "Company") was incorporated in the State of Delaware in July 2015. The Company is a biopharmaceutical company developing engineered natural killer ("NK") cell therapies to treat cancer and autoimmune disease. The Company is focused on leveraging the natural potent power of NK cells to identify and kill abnormal cells and recruit adaptive immune effectors to generate responses that are specific and durable. Nkarta is combining its NK-cell expansion platform technology with proprietary cell engineering technologies to generate an abundant supply of NK cells, engineer enhanced NK-cell recognition of therapeutic targets, and improve persistence for sustained activity in the body. Nkarta’s goal is to develop off-the-shelf NK-cell therapy product candidates to improve outcomes for patients. The Company’s operations are based in South San Francisco, California, and it operates in one segment. Liquidity and Management Plans The accompanying unaudited condensed financial statements have been prepared assuming that the Company will continue as a going concern. Since inception, the Company has devoted substantially all of its efforts to organizing and staffing, business planning, raising capital, conducting preclinical studies and initiating clinical studies, and has not realized substantial revenues from its planned principal operations. In addition, the Company has a limited operating history, has incurred operating losses since inception and expects that it will continue to incur net losses into the foreseeable future as it continues its research and development activities. As of March 31, 2024, the Company had an accumulated deficit of $465.0 million and cash, cash equivalents, restricted cash and investments of $450.0 million. Management plans to continue to incur substantial costs in order to conduct research and development activities for which additional capital will be needed. The Company intends to raise such capital through debt or equity financings or other arrangements to fund operations. Management believes that the Company’s current cash, cash equivalents, restricted cash and investments will provide sufficient funds to enable the Company to meet its obligations for at least twelve months from the filing date of this report. On March 17, 2023, the Company filed a Registration Statement on Form S-3, as amended by the Form S-3/A filed on April 24, 2023 (the "Shelf Registration Statement"), covering the offer and sale from time to time, pursuant to Rule 415 of the Securities Act of 1933, as amended (the "Securities Act"), of up to $350.0 million in aggregate offering price of shares of the Company’s common stock, shares of the Company’s preferred stock, debt securities, warrants, rights and/or units, including up to $120.0 million in aggregate offering price of shares of the Company’s common stock, shares of the Company’s preferred stock, debt securities, warrants, rights and/or units registered on the Company’s Registration Statement on Form S-3 declared effective by the Securities and Exchange Commission (the "SEC") on September 2, 2021 (the "Prior Registration Statement") that have not yet been sold. The Shelf Registration Statement was declared effective by the SEC on May 5, 2023. On August 12, 2021, the Company entered into a sales agreement with Cowen and Company, LLC, a sales agent, to provide for the offering, issuance and sale of up to an aggregate of $150.0 million of the Company’s common stock through an “at-the-market” equity offering program (the "ATM Offering Program") pursuant to the Prior Registration Statement and subject to the limitations thereof. For the three months ended March 31, 2024, no sales of the Company’s common stock were made pursuant to the ATM Offering Program. On March 27, 2024, the Company completed an underwritten public offering utilizing the Shelf Registration Statement, pursuant to which it sold an aggregate of (i) 21,010,000 shares of its common stock at a price of $10.00 per share, and (ii) pre-funded warrants to purchase 3,000,031 shares of common stock at a price of $9.9999 per pre-funded warrant. The pre-funded warrants can be exercised at any time after issuance for an exercise price of $0.0001 per share, subject to certain ownership limitations. The Company raised $240.1 million in gross proceeds before underwriting discounts, commissions and other expenses of $15.0 million. See Note 9 for additional detail.

Organization and Description of Business

3 Months Ended

Mar. 31, 2024

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Organization and Description of Business

1. Organization and Description of Business

Description of the Business

Nkarta, Inc. ("Nkarta" or the "Company") was incorporated in the State of Delaware in July 2015. The Company is a biopharmaceutical company developing engineered natural killer ("NK") cell therapies to treat cancer and autoimmune disease. The Company is focused on leveraging the natural potent power of NK cells to identify and kill abnormal cells and recruit adaptive immune effectors to generate responses that are specific and durable. Nkarta is combining its NK-cell expansion platform technology with proprietary cell engineering technologies to generate an abundant supply of NK cells, engineer enhanced NK-cell recognition of therapeutic targets, and improve persistence for sustained activity in the body. Nkarta’s goal is to develop off-the-shelf NK-cell therapy product candidates to improve outcomes for patients. The Company’s operations are based in South San Francisco, California, and it operates in one segment.

Liquidity and Management Plans

The accompanying unaudited condensed financial statements have been prepared assuming that the Company will continue as a going concern. Since inception, the Company has devoted substantially all of its efforts to organizing and staffing, business planning, raising capital, conducting preclinical studies and initiating clinical studies, and has not realized substantial revenues from its planned principal operations. In addition, the Company has a limited operating history, has incurred operating losses since inception and expects that it will continue to incur net losses into the foreseeable future as it continues its research and development activities. As of March 31, 2024, the Company had an accumulated deficit of $465.0 million and cash, cash equivalents, restricted cash and investments of $450.0 million.

Management plans to continue to incur substantial costs in order to conduct research and development activities for which additional capital will be needed. The Company intends to raise such capital through debt or equity financings or other arrangements to fund operations. Management believes that the Company’s current cash, cash equivalents, restricted cash and investments will provide sufficient funds to enable the Company to meet its obligations for at least twelve months from the filing date of this report.

On March 17, 2023, the Company filed a Registration Statement on Form S-3, as amended by the Form S-3/A filed on April 24, 2023 (the "Shelf Registration Statement"), covering the offer and sale from time to time, pursuant to Rule 415 of the Securities Act of 1933, as amended (the "Securities Act"), of up to $350.0 million in aggregate offering price of shares of the Company’s common stock, shares of the Company’s preferred stock, debt securities, warrants, rights and/or units, including up to $120.0 million in aggregate offering price of shares of the Company’s common stock, shares of the Company’s preferred stock, debt securities, warrants, rights and/or units registered on the Company’s Registration Statement on Form S-3 declared effective by the Securities and Exchange Commission (the "SEC") on September 2, 2021 (the "Prior Registration Statement") that have not yet been sold. The Shelf Registration Statement was declared effective by the SEC on May 5, 2023.

On August 12, 2021, the Company entered into a sales agreement with Cowen and Company, LLC, a sales agent, to provide for the offering, issuance and sale of up to an aggregate of $150.0 million of the Company’s common stock through an “at-the-market” equity offering program (the "ATM Offering Program") pursuant to the Prior Registration Statement and subject to the limitations thereof. For the three months ended March 31, 2024, no sales of the Company’s common stock were made pursuant to the ATM Offering Program.

On March 27, 2024, the Company completed an underwritten public offering utilizing the Shelf Registration Statement, pursuant to which it sold an aggregate of (i) 21,010,000 shares of its common stock at a price of $10.00 per share, and (ii) pre-funded warrants to purchase 3,000,031 shares of common stock at a price of $9.9999 per pre-funded warrant. The pre-funded warrants can be exercised at any time after issuance for an exercise price of $0.0001 per share, subject to certain ownership limitations. The Company raised $240.1 million in gross proceeds before underwriting discounts, commissions and other expenses of $15.0 million. See Note 9 for additional detail.