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(Corrects spelling of "Movantik" throughout)
By Natalie Grover
Sept 16 (Reuters) - The U.S. Food and Drug Administrationapproved an oral therapy to treat opioid-induced constipationdeveloped by Nektar Therapeutics and AstraZeneca Plc .
The decision opens the door for peripherally acting muopioid receptor antagonists, which have been linked withcardiovascular risk in the past.
This class of opioid-induced constipation (OIC) drugs aredesigned to fight the effects of opioid painkillers on the gut without compromising centrally mediated pain relief.
The drug, known generically as naloxegol, will be sold underthe trade name Movantik, and is indicated for patients onopioids for pain unrelated to cancer. (http://1.usa.gov/1qbvs7U)
It will benefit from a two-three year advantage over othertherapies undergoing development, Roth Capital Partners analystDebjit Chattopadhyay said.
An FDA panel had recommended in June that largecardiovascular safety trials were not needed before approval forthis class of drugs.
The agency on Tuesday asked the developers to conduct apostmarketing study to further evaluate the potential risk ofheart-related side-effects.
The panel had met after a late-stage study showed CubistPharmaceuticals Inc's OIC drug, Entereg, was associatedwith a greater number of heart attacks.
Constipation is the most frequent side effect associatedwith long-term opioid therapy.
Only 40-50 percent of patients experience effective relieffrom currently available over-the-counter medicines or SucampoPharmaceutical's stool softener Amitiza, Nektar said.
Movantik will likely compete with Salix Pharmaceuticals Ltd and Progenics Pharmaceutical's subcutaneousinjection Relistor - slated for an FDA decision this month forthe same patient population.
Relistor was first approved in 2008 to treat OIC in severelyill patients, receiving palliative care, who were unresponsiveto laxatives.
AstraZeneca's deep pockets and the fact that Movantik isorally administered gives it the best possible marketpositioning, Chattopadhyay said.
"If you look at the way they structured the deal withNektar, clearly they think this is a multi-billion dollar drug,"he said.
Movantik is also being reviewed by European and Canadianregulators.
Chattopadhyay said he expects it to launch in the UnitedStates by the first quarter of 2015, and in Europe the followingquarter.
BIG-TICKET DRUG?
Nektar discovered Movantik, using its proprietarytechnology, and licensed the compound to AstraZeneca in 2009.
The company is eligible to receive up to $235 million ifMovantik achieves some regulatory milestones, and additionalsales milestones of up to $375 million.
Tuesday's approval is crucial for Nektar, which has beenunable to significantly benefit from prior deals - despitemultiple successful approvals for drugs co-developed by it.
The appointment of Chief Executive Howard Robin in 2007 ledto a marked shift in strategy, which evolved in order to bettermonetize Nektar's technology.
"Since Robin has come on board...all cases they are gettinga high dollar amount up front and pretty significant milestones,with high double digit (20-30 percent) royalty streams,"Chattopadhyay said. (Reporting by Natalie Grover in Bangalore; Editing by JoyjeetDas)
