Nektar Therapeutics (Nektar) (NASDAQ: NKTR) is an American biopharmaceutical company. The company was founded in 1990 and is based in San Francisco, California. The company develops new drug candidates by applying its proprietary PEGylation and advanced polymer conjugate technologies to modify chemical structure of substances. It is a technology supplier to a number of pharmaceutical companies including Affymax, Amgen, Merck, Pfizer and UCB Pharma, etc. The company developed the world's first inhalable non-injectable insulin, Exubera, which was awarded as the bronze award by Wall Street Journal for its technological breakthrough.

The company is engaged in developing a propriety pipeline of drug candidates for several therapeutic areas including oncology, pain, anti-infectives, anti-viral and immunology. The company's research and development involve in small molecule and biologic drug candidates. Its drug candidate base consists of naloxegol (Movantik), a Phase III oral opioid antagonist, etirinotecan pegol, a topoisomerase inhibitor under Phase III clinical study as of 2012, NKTR 061, NKTR-181, NKTR-214, etc.

In 2013, the company was assignment a patent which was developed by the company and other four co-inventors. The products of the company is served as a supplement to improve the pharmacokinetics, pharmacodynamics, half-life, bioavailability and other areas of drugs for the patients worldwide. As of March 2014, the company had an market capitalization of $1.7 billion with an enterprise value of $1.67 billion.

Etirinotecan pegol was in the phase III BEACON trial, and is in the I-SPY2 adaptive clinical trial for breast cancer.