NantKwest, Inc. (formerly Conkwest, Inc.), a clinical-stage immunotherapy company, proceeded with an initial public offering (IPO) of 8,288,000 shares of its common stock at a price to the public of $25.00 per share. At its offering price, NantKwest reached a a fully diluted market capitalization of $2.6 billion,making it the largest development-stage biotech to go public in the US, according to Renaissance Capital, an investment advisory firm.

The shares began trading on The Nasdaq Global Select Market on July 28, 2015. In addition, NantKwest granted the underwriters a 30-day option to purchase up to an additional 1,243,200 shares of its common stock. Concurrently with the initial public offering, NantKwest is also selling 680,000 shares of its common stock in a separate private placement to Celgene Corporation, an existing stockholder, at the initial public offering price of $25.00 per share.

NantKWest is lead by Chairman and Chief Executive Officer, Dr. Soon-Shiong, a physician, surgeon and scientist, and known for developing Abraxane a protein nanoparticle albumin-bound delivery technology for the treatment of cancer. Dr. Soon-Shiong founded the global pharmaceutical companies American Pharmaceutical Partners and Abraxis BioScience and served as chairman and CEO of both companies from 1997 to 2010. Both companies were acquired in multi-billion transactions, respectively in 2008 and 2010 (Celgene acquired Abraxis BioScience) in 2010. In 2011, he founded NantWorks, an ecosystem of healthcare and pharmaceutical development companies.

The company is tapping into its expertise in immunotherapies, partificularly of so-called natural killer (NK) cells, which are the body's first line of defense to destroy abnormal cells, such as cancer or virally-infected cells, without prior exposure or activation by other support molecules required to activate adaptive immune cells such as T-cells. The company has a proprietary NK cell line and an integrated discovery ecosystem for use in discovering and developing immunotherapies.

Source: NantKwest