Description of Business	6 Months Ended
Jun. 30, 2020
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Description of Business	1. Description of Business Organization NantKwest, Inc., or NantKwest, was incorporated in Illinois on October 7, 2002 under the name ZelleRx Corporation. On January 22, 2010, the company changed its name to Conkwest, Inc., and on July 10, 2015, the company changed its name to NantKwest, Inc. In March 2014, the company redomesticated from the State of Illinois to the State of Delaware and the Illinois company ceased to exist. We are a pioneering clinical-stage immunotherapy biotechnology company headquartered in San Diego, California with certain operations in Culver City and El Segundo, California and Woburn, Massachusetts. In these notes, the terms “we,” “our,” “the company” and “us” refer to NantKwest. We are focused on harnessing the power of the innate immune system by using our natural killer cells, or NK cells, to treat cancer and viral infectious diseases. A critical aspect of our strategy is to invest significantly in innovating new therapeutic candidates, based upon our proprietary activated NK, or aNK, cell platform, and conducting clinical testing and scale manufacturing of our most promising biologic product candidates. We hold the exclusive right to commercialize aNK cells, a commercially viable NK cell line, and a wide range of genetically modified derivatives capable of killing cancer and virally infected cells. We own corresponding United States, or U.S., and foreign composition and methods-of-use patents and applications covering the cells, improvements, methods of expansion and manufacture and use of aNK cells and their improvements as therapeutics to treat a spectrum of clinical conditions. We also license exclusive commercial rights to a high-affinity CD16 receptor expressing enhancement of our aNK cell platform, covered in a portfolio of U.S. and foreign composition and methods-of-use patents and applications covering both the clinical use as a therapeutic to treat cancers in combination with antibody products, as well as the non-clinical use in laboratory testing of monoclonal antibodies. We have non-exclusively licensed or sub-licensed our high-affinity CD16 bearing aNK cell platform and corresponding intellectual property to numerous pharmaceutical and biotechnology companies for such non-clinical uses. Liquidity On June 29, 2020, the company closed an underwritten public offering of an aggregate of 8,521,500 shares of common stock, which included 4,811,500 shares issued to the public at a price of $9.50 per share (which includes 1,111,500 shares sold to the public upon full exercise of the underwriters’ option to purchase additional shares at a public offering price of $9.50 per share), less underwriting discounts and commissions, and 3,710,000 shares issued to our Chairman, CEO and principal stockholder, Dr. Patrick Soon-Shiong, at a price of $12.12 per share, less underwriting discounts and commissions. All of the shares were offered by the company. Including the underwriters’ option exercise, the aggregate gross proceeds from the offering were approximately $90.7 million, before deducting underwriting discounts, commissions and other offering expenses payable by the company of approximately $4.4 million. Estimated issuance cost totaling $0.5 million were unpaid as of June 30, 2020 and have been included in accounts payable and accrued expenses on the company’s condensed consolidated balance sheets as of such date. As of June 30, 2020, the company had an accumulated deficit of $700.7 million. We also had negative cash flow from operations of $29.1 million during the six months ended June 30, 2020. The company will likely need additional capital to further fund development of, and seek regulatory approvals for, our product candidates, and to begin to commercialize any approved products. We are currently focused primarily on the development of immunotherapeutic treatments for cancers and debilitating viral infections using targeted cancer and viral killing cell lines, and we believe such activities will result in the company’s continued incurrence of significant research and development and other expenses related to those programs. If the clinical trials for any of the company’s product candidates fail or produce unsuccessful results and those product candidates do not gain regulatory approval, or if any of our product candidates, if approved, fail to achieve market acceptance, we may never become profitable. Even if the company achieves profitability in the future, it may not be able to sustain profitability in subsequent periods. We intend to cover our future operating expenses through cash and cash equivalents and marketable debt securities on hand and through a combination of equity offerings, debt financings, government or other third-party funding, marketing and distribution arrangements and other collaborations, strategic alliances, and licensing arrangements. Additional financing may not be available to us when needed and, if available, financing may not be obtained on terms favorable to the company or its stockholders. While we expect our existing cash, and cash equivalents and marketable debt securities will enable us to fund operations and capital expenditure requirements for at least the next 12 months, we may not have sufficient funds to reach commercialization. Failure to obtain adequate financing when needed may require us to delay, reduce, limit, or terminate some or all of our development programs or future commercialization efforts or grant rights to develop and market product candidates that we might otherwise prefer to develop and market ourselves, which could adversely affect our ability to operate as a going concern. If we raise additional funds from the issuance of equity securities, substantial dilution to existing stockholders may result. If we raise additional funds by incurring debt financing, the terms of the debt may involve significant cash payment obligations, as well as covenants and specific financial ratios that may restrict our ability to operate our business.

Description of Business

6 Months Ended

Jun. 30, 2020

Organization Consolidation And Presentation Of Financial Statements [Abstract]

1. Description of Business

Organization

NantKwest, Inc., or NantKwest, was incorporated in Illinois on October 7, 2002 under the name ZelleRx Corporation. On January 22, 2010, the company changed its name to Conkwest, Inc., and on July 10, 2015, the company changed its name to NantKwest, Inc. In March 2014, the company redomesticated from the State of Illinois to the State of Delaware and the Illinois company ceased to exist. We are a pioneering clinical-stage immunotherapy biotechnology company headquartered in San Diego, California with certain operations in Culver City and El Segundo, California and Woburn, Massachusetts. In these notes, the terms “we,” “our,” “the company” and “us” refer to NantKwest.

We are focused on harnessing the power of the innate immune system by using our natural killer cells, or NK cells, to treat cancer and viral infectious diseases. A critical aspect of our strategy is to invest significantly in innovating new therapeutic candidates, based upon our proprietary activated NK, or aNK, cell platform, and conducting clinical testing and scale manufacturing of our most promising biologic product candidates.

We hold the exclusive right to commercialize aNK cells, a commercially viable NK cell line, and a wide range of genetically modified derivatives capable of killing cancer and virally infected cells. We own corresponding United States, or U.S., and foreign composition and methods-of-use patents and applications covering the cells, improvements, methods of expansion and manufacture and use of aNK cells and their improvements as therapeutics to treat a spectrum of clinical conditions.

We also license exclusive commercial rights to a high-affinity CD16 receptor expressing enhancement of our aNK cell platform, covered in a portfolio of U.S. and foreign composition and methods-of-use patents and applications covering both the clinical use as a therapeutic to treat cancers in combination with antibody products, as well as the non-clinical use in laboratory testing of monoclonal antibodies. We have non-exclusively licensed or sub-licensed our high-affinity CD16 bearing aNK cell platform and corresponding intellectual property to numerous pharmaceutical and biotechnology companies for such non-clinical uses.

Liquidity

On June 29, 2020, the company closed an underwritten public offering of an aggregate of 8,521,500 shares of common stock, which included 4,811,500 shares issued to the public at a price of $9.50 per share (which includes 1,111,500 shares sold to the public upon full exercise of the underwriters’ option to purchase additional shares at a public offering price of $9.50 per share), less underwriting discounts and commissions, and 3,710,000 shares issued to our Chairman, CEO and principal stockholder, Dr. Patrick Soon-Shiong, at a price of $12.12 per share, less underwriting discounts and commissions. All of the shares were offered by the company. Including the underwriters’ option exercise, the aggregate gross proceeds from the offering were approximately $90.7 million, before deducting underwriting discounts, commissions and other offering expenses payable by the company of approximately $4.4 million. Estimated issuance cost totaling $0.5 million were unpaid as of June 30, 2020 and have been included in accounts payable and accrued expenses on the company’s condensed consolidated balance sheets as of such date.

As of June 30, 2020, the company had an accumulated deficit of $700.7 million. We also had negative cash flow from operations of $29.1 million during the six months ended June 30, 2020. The company will likely need additional capital to further fund development of, and seek regulatory approvals for, our product candidates, and to begin to commercialize any approved products.

We are currently focused primarily on the development of immunotherapeutic treatments for cancers and debilitating viral infections using targeted cancer and viral killing cell lines, and we believe such activities will result in the company’s continued incurrence of significant research and development and other expenses related to those programs. If the clinical trials for any of the company’s product candidates fail or produce unsuccessful results and those product candidates do not gain regulatory approval, or if any of our product candidates, if approved, fail to achieve market acceptance, we may never become profitable. Even if the company achieves profitability in the future, it may not be able to sustain profitability in subsequent periods. We intend to cover our future operating expenses through cash and cash equivalents and marketable debt securities on hand and through a combination of equity offerings, debt financings, government or other third-party funding, marketing and distribution arrangements and other collaborations, strategic alliances, and licensing arrangements. Additional financing may not be available to us when needed and, if available, financing may not be obtained on terms favorable to the company or its stockholders.

While we expect our existing cash, and cash equivalents and marketable debt securities will enable us to fund operations and capital expenditure requirements for at least the next 12 months, we may not have sufficient funds to reach commercialization. Failure to obtain adequate financing when needed may require us to delay, reduce, limit, or terminate some or all of our development programs or future commercialization efforts or grant rights to develop and market product candidates that we might otherwise prefer to develop and market ourselves, which could adversely affect our ability to operate as a going concern. If we raise additional funds from the issuance of equity securities, substantial dilution to existing stockholders may result. If we raise additional funds by incurring debt financing, the terms of the debt may involve significant cash payment obligations, as well as covenants and specific financial ratios that may restrict our ability to operate our business.