NEKTAR LAUNCHES STUDY OF PEGYLATED IRINOTECAN

Nektar Therapeutics has initiated a Phase I clinical trial program to evaluate the safety, tolerability and pharmacokinetics of NKTR-102 (PEG-irinotecan), an innovative new oncology therapy with the potential to treat patients with refractory solid tumors, the company announced.

NKTR-102 is a PEGylated form of irinotecan, a chemotherapeutic agent used for the treatment of solid tumors. The Phase I trial is an open-label, dose-escalation study that will enroll up to 30 patients at multiple cancer research sites in the U.S.

"In preclinical studies in tumor-bearing mice, NKTR-102 resulted in significantly higher reduction in tumor growth than irinotecan in colon, lung and breast tumors," David Johnston, senior vice president of R&D, said. "Furthermore, preclinical studies revealed that NKTR-102 was well-tolerated with significant reduction of neutropenia and diarrahea, two debilitating side effects of non-PEGylated irinotecan."

NKTR-102 is synthesized by conjugating a Nektar PEG to irinotecan. Irinotecan is a cytotoxic anticancer agent widely used to treat colorectal, lung and esophageal solid tumors. In the U.S. it is indicated as a component of first-line therapy in combination with 5-fluorouracil and leucovorin for patients with metastatic carcinoma of the colon or rectum, according to the company. Based on preclinical studies and experience with PEG technology, Nektar believes that following intravenous administration of NKTR-102, irinotecan will be slowly released from NKTR-102, resulting in prolonged systemic exposure of irinotecan.

Nektar said its 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.