NEW YORK (TheStreet) -- Shares of AstraZeneca (AZN) - Get Report dipped 0.18% to $73.65 in afternoon trading Tuesday despite the FDA's approval of the constipation drug Movantik, developed by AstraZeneca and Nektar Therapeutics (NKTR) - Get Report .
The drug is an oral treatment for opioid-induced constipation in adults with chronic non-cancer pain. A common side effect of the opioid class of drugs is constipation, but Movantik, or naloxegol, is part of a class of drugs called peripherally acting opioid receptor antagonists, which reduce the constipating effects.
The FDA's approval is a positive step for this class of drugs that had previously been linked to cardiovascular risk.
An FDA panel said in June that large cardiovascular safety trials were not necessary prior to approval for this class of drugs, according to Reuters. The FDA asked the two companies on Tuesday to conduct a post-marketing study to further determine the possible risk of cardiovascular side effects.
Eli Lilly (LLY) - Get Report also announced Tuesday it would pay AstraZeneca $500 million in development and regulatory milestone payments as part of a new agreement to co-develop and market AstraZeneca's Alzheimer's treatment ASD3293, which has already completed phase I trials.
Eli Lilly will handle the clinical development, while AstraZeneca will handle manufacturing.
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