Organization and Description of Business	9 Months Ended
Sep. 30, 2020
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”) cells to fight cancer. 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 expansion platform technology with proprietary cell engineering technologies to generate an abundant supply of NK cells, engineer enhanced NK cell recognition of tumor targets, and improve persistence for sustained activity in the body for the treatment of cancer. 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. Initial Public Offering On July 14, 2020, the Company completed its initial public offering (“IPO”). The Company’s Registration Statement on Form S-1 (File No. 333-239301) relating to the IPO was declared effective by the Securities and Exchange Commission (“SEC”) on July 9, 2020. The shares began trading on the Nasdaq Global Select Market on July 10, 2020. The Company issued 16,100,000 shares of its common stock, including 2,100,000 shares associated with the full exercise of the underwriters’ option to purchase additional shares, at an offering price of $18.00 per share. Immediately prior to the closing of the Company’s IPO on July 14, 2020, all outstanding shares of the Company’s convertible preferred stock were converted into 14,689,215 shares of the Company’s common stock. In aggregate, the shares issued in the IPO generated approximately $265.1 million in net proceeds after deducting underwriting discounts and commissions and other offering costs. Liquidity and Management Plans The accompanying unaudited condensed financial statements have been prepared assuming that the Company will continue as a going concern. However, 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 September 30, 2020, the Company had an accumulated deficit of $100.1 million and cash, cash equivalents, restricted cash and short-term investments of $330.2 million. Management plans to continue to incur substantial costs in order to conduct research and development activities and additional capital will be needed to undertake these activities. 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 short-term investments, including the net proceeds of approximately $265.1 million from the closing of its IPO in July 2020 as described above, together with the aggregate gross proceeds of $64.4 million from the issuance of 27,066,206 shares of the Series B preferred stock upon the closing of the Series B Milestone Closing (defined below) on July 1, 2020, will provide sufficient funds to enable the Company to meet its obligations for at least twelve months from the filing date of this report.

Organization and Description of Business

9 Months Ended

Sep. 30, 2020

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”) cells to fight cancer. 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 expansion platform technology with proprietary cell engineering technologies to generate an abundant supply of NK cells, engineer enhanced NK cell recognition of tumor targets, and improve persistence for sustained activity in the body for the treatment of cancer. 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.

Initial Public Offering

On July 14, 2020, the Company completed its initial public offering (“IPO”). The Company’s Registration Statement on Form S-1 (File No. 333-239301) relating to the IPO was declared effective by the Securities and Exchange Commission (“SEC”) on July 9, 2020. The shares began trading on the Nasdaq Global Select Market on July 10, 2020. The Company issued 16,100,000 shares of its common stock, including 2,100,000 shares associated with the full exercise of the underwriters’ option to purchase additional shares, at an offering price of $18.00 per share. Immediately prior to the closing of the Company’s IPO on July 14, 2020, all outstanding shares of the Company’s convertible preferred stock were converted into 14,689,215 shares of the Company’s common stock. In aggregate, the shares issued in the IPO generated approximately $265.1 million in net proceeds after deducting underwriting discounts and commissions and other offering costs.

Liquidity and Management Plans

The accompanying unaudited condensed financial statements have been prepared assuming that the Company will continue as a going concern. However, 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 September 30, 2020, the Company had an accumulated deficit of $100.1 million and cash, cash equivalents, restricted cash and short-term investments of $330.2 million.

Management plans to continue to incur substantial costs in order to conduct research and development activities and additional capital will be needed to undertake these activities. 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 short-term investments, including the net proceeds of approximately $265.1 million from the closing of its IPO in July 2020 as described above, together with the aggregate gross proceeds of $64.4 million from the issuance of 27,066,206 shares of the Series B preferred stock upon the closing of the Series B Milestone Closing (defined below) on July 1, 2020, will provide sufficient funds to enable the Company to meet its obligations for at least twelve months from the filing date of this report.