The US Food and Drug Administration (FDA) revised its draft guidance provides information on the implementation of section 505(o)(3) of the Federal Food, Drug, and Cosmetic Act (the FD&C Act) (21 U.S.C. 355(o)(3)), which authorizes FDA to require certain postmarketing studies and clinical trials for prescription drugs approved under section 505(c) of the FD&C Act and biological products approved under section 351 of the Public Health Service Act (the PHS Act) (42 U.S.C. 262).

The draft guidance, first issued for comment in 2011, is being revised to detail the factors the agency considers when determining whether a postmarketing study or clinical trial will be required for a drug or biologic or whether postmarketing reports and the agency’s active postmarket risk identification and analysis (ARIA) system are sufficient to assess a product’s risks in the postmarket setting.

The guidance is also being updated to reflect a provision of the 2018 Substance Use-Disorder Prevention that Promotes Opioid Recovery and Treatment for Patients and Communities Act (SUPPORT Act) that enables FDA to require post-marketing studies under section 505(o)(3) to assess the potential reduction inefficacy of a drug. While the SUPPORT Act focuses on opioids and other controlled substances, FDA notes that “at this time, the agency does not intend to treat controlled substances differently than other prescription drugs.”

The revised draft guidance provides a list of four examples of clinical trials to assess risks related to reduced effectiveness; though, in line with the agency’s statement on not differentiating between controlled substances and other drugs, does not include any examples of trials involving opioids or other controlled substances.