Investors in pain drug developer ­ QRxPharma face a six-month wait before finding out if it’s third time lucky with the US Food and Drug Administration.

An application for the company’s MOXDUO immediate-release pain drug, which is a combination of ­morphine and oxycodone, was filed last week after a data mix-up delivered the company’s second rejection in August. The first rejection came in June 2012, when the FDA asked for more data as a result of the drug’s dual structure.