Press Release

<< Back
Jul 26, 2007
Anti-Tumor Activity and Pharmacokinetic Properties of NKTR-102 (PEG-irinotecan) to be Presented at Upcoming Oncology Meeting

SAN CARLOS, Calif., July 26, 2007 /PRNewswire-FirstCall via COMTEX News Network/ --

The first peer- reviewed presentations of preclinical data for Nektar Therapeutics' (Nasdaq: NKTR) proprietary product, NKTR-102 (PEG-irinotecan) is scheduled to be presented at an upcoming scientific meeting focused on oncology.

Nektar is developing NKTR-102, a PEGylated form of irinotecan invented by Nektar using its world-leading small molecule PEGylation technology platform. Irinotecan is an important chemotherapeutic agent used for the treatment of solid tumors, including colorectal and lung cancers. By applying Nektar's small molecule PEGylation technology to irinotecan, NKTR-102 may prove to be a more powerful and tolerable anti-tumor agent.

In preclinical studies in tumor-bearing mice, NKTR-102 resulted in significantly reduced tumor growth compared to irinotecan in colon, lung and breast tumors. These studies indicate that Nektar's small molecule PEGylation technology may enable NKTR-102 to have prolonged systemic exposure following intravenous administration. Furthermore, preclinical studies in mice indicate that NKTR-102 was well-tolerated with significant reduction of neutropenia and diarrhea, two debilitating side effects of non-PEGylated irinotecan.

"Nektar's proprietary small molecule PEGylation technology is breaking new ground, demonstrating the potential to deliver more powerful doses of chemotherapeutic agents while mitigating many of the severe side effects associated with chemotherapy," said Howard W. Robin, Nektar's President and Chief Executive Officer. "There are many small molecule therapeutics that can benefit from improved efficacy and safety profiles and we believe that with our innovative technology, Nektar is in a leadership position in developing these improved medicines."

    Two upcoming data presentations are scheduled:

    *  Sept. 27, 2007, 8-11 am (Central European Standard Time) 14th Annual
       European Cancer Conference (ECCO), International Conference Centre,
       Barcelona, Spain.

       --  A poster presentation of preclinical data focused on anti-tumor
           activity and pharmacokinetics of NKTR-102 (PEG-irinotecan);

       --  A poster presentation of preclinical data focused on the manner in
           which PEGylation governs the disposition and metabolism of
           irinotecan following administration of NKTR-102 (PEG-irinotecan).

More information about the 14th Annual European Cancer Conference is available at: http://www.fecs.be/emc.asp?pageId=1228&Type=P#Introduction_

Nektar PEGylation Platform

Nektar PEGylation technology can enhance the properties of therapeutic agents by increasing drug circulation time in the bloodstream, decreasing immunogenicity and dosing frequency, increasing bioavailability and improving drug solubility and stability. It can also be used to modify pharmaceutical agents to preferentially target certain systems within the body. It is a technique in which non-toxic polyethylene glycol (PEG) polymers are attached to therapeutic agents, and it is applicable to most major drug classes, including proteins, peptides, antibody fragments, small molecules, and other drugs.

Nektar PEGylation technology is also used in eight additional approved partnered products in the U.S. or Europe today, including Roche's PEGASYS(R) for hepatitis C and Amgen's Neulasta(R) for neutropenia.

About Nektar

Nektar Therapeutics is a biopharmaceutical company that develops and enables differentiated therapeutics with its industry-leading PEGylation and pulmonary drug development technology platforms. Nektar PEGylation and pulmonary technology, expertise, manufacturing capabilities have enabled nine approved products for partners, which include the world's leading pharmaceutical and biotechnology companies. Nektar also develops its own products by applying its PEGylation and pulmonary technology platforms to existing medicines with the objective to enhance performance, such as improving efficacy, safety and compliance.

This press release contains forward-looking statements regarding the potential of the company's PEGylation technology platform and NKTR-102. These forward-looking statements involve important risks and uncertainties, including but not limited to: (i) preclinical testing and clinical trials for NKTR-102 are long, expensive and uncertain processes, (ii) because the NKTR- 102 product development programs are in the early phases of clinical development, the risk of failure is high and can occur at any stage of development, (iii) the company may fail to obtain regulatory approval of NKTR- 102, (iv) potential competition from approved drugs or drugs under development that may be safe and effective for the same indication as that targeted by NKTR-102, and (v) the company's patent applications for NKTR-102 may fail to issue; patents that have issued may not be enforceable; or unanticipated intellectual property licenses from third parties may be required in the future. Other important risks and uncertainties are detailed in the company's reports and other filings with the SEC including its most recent Annual Report on Form 10-K and Quarterly Report on Form 10-Q. Actual results could differ materially from the forward-looking statements contained in this press release. The company undertakes no obligation to update forward-looking statements, whether as a result of new information, future events, or otherwise. No information regarding or presented at the scientific meetings referred to above (or contained at the Internet links provided) is intended to be incorporated by reference in this press release.

SOURCE Nektar Therapeutics

Tim Warner, +1-650-283-4915, twarner@nektar.com, or Stephan Herrera, +1-415-488-7699,
sherrera@nektar.com, or Jennifer Ruddock, +1-650-631-4954, jruddock@nektar.com
http://www.nektar.com

Copyright (C) 2007 PR Newswire. All rights reserved

News Provided by COMTEX