Purdue epidemiological studies indicate reformulation of OxyContin had a positive effect on abuse and misuse of the drug, but the company says continued monitoring is needed to assess whether the positive trend continues.

FDA draft guidance says there is no clear epidemiologic strategy for gathering the data to demonstrate that has reduced abuse; the agency outlines four possible kinds of abuse deterrence claims, three of which can be obtained through pre-market studies.

FDA’s Anesthetic and Analgesic Drug Products Advisory Committee recommends against approval of Zogenix’s Zohydro ER as it seeks safer formulations and stricter REMS for all extended-release/long-acting opioids.