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Nektar shares rise on safety study of pain drug

NEW YORK (AP) -- Shares of Nektar Therapeutics advanced Wednesday after the company reported data from a clinical trial of NKTR-181, a pain drug that Nektar says may be less addictive than older medications.

The company said NKTR-181 was rated similar to placebo and below oxycodone on measurements of "drug liking" and how high patients felt after taking it.

Nektar says its drug enters the brain slowly, reducing the feeling of euphoria that is associated with abuse and addiction to drugs. The result comes from a trial intended to test the drug's abuse potential.

NKTR-181 is an opioid pain drug intended to be taken twice a day. Nektar is testing it in mid-stage clinical trials.

Oxycodone is the main ingredient in Purdue Pharma's pain drug OxyContin, which was taken off the market in 2010 because of widespread concerns about people who were abusing the drug to get high. OxyContin was replaced with a newer version that was designed to be harder to abuse, and other companies have also been studying and marketing abuse-resistant pain drugs.

Shares of Nektar rose $1.01, or 10.4 percent, to $10.83 in afternoon trading Wednesday. They peaked at $11.34 in mid-April and traded as low as $5.65 last November over the past year.