The FDA has accepted Merck & Co Inc's (NYSE: MRK) marketing application seeking approval for gefapixant, for review.

• The selective P2X3 receptor antagonist is being developed to treat refractory chronic cough or unexplained chronic cough in adults.
• The application will be discussed at an upcoming advisory committee meeting.
• The agency's target action date is set of December 21.
• The NDA is based on mixed results from the COUGH-1 and COUGH-2 trials.
• In COUGH-1, the 45-mg dose of gefapixant resulted in an 18.5% estimated relative risk reduction in 24-hour coughs per hour at week 12, its primary endpoint. In COUGH-2, the same dose drove a 14.6% relative risk reduction at week 24. The 15-mg dose failed in both trials.
• Price Action: MRK shares were up 0.94% at $73.30 in premarket trading on the last check Monday.