Nektar Therapeutics (NKTR)

[surf1944]

8:39AM Nektar Therapeutics presents 'positive' proof-of-concept clinical data for its new opioid molecule, NKTR-181 (NKTR) 6.98 : Co announced a presentation of positive clinical data for NKTR-181, its new oral opioid analgesic molecule, at the 2012 American Academy of Pain Medicine's 28th Annual Meeting. NKTR-181 is a novel mu-opioid agonist molecule, which was designed to have a slow rate of entry into the brain to reduce the attractiveness of the molecule as a target of abuse and to reduce its CNS-mediated side effects. Using pupil constriction as a measure of the onset of central opioid effect, the study showed that NKTR-181 enters the brain slowly and produces centrally-mediated opioid effects that are dose-dependent and statistically meaningful (P<0.001) following twice daily oral doses of 200-400 mg. Further, NKTR-181 enters the CNS from the plasma at a rate approximately ten-times slower than historical published rates for oxycodone. NKTR-181's slow rate of entry into the CNS may reduce the euphoria and other CNS side effects that are associated with rapid CNS uptake of current standard opioid therapies. In a separate presentation of preclinical data at the AAPM Meeting, NKTR-181 resulted in less sedation and abuse liability as compared to oxycodone in multiple animal models across a wide range of doses. As predicted from its molecular design, NKTR-181 has a reduced rate of entry into the brain in rodents. This feature contributed to a 30-fold shift in the dose-response for abuse liability and a 10-fold shift in the dose response for sedation relative to oxycodone.