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REMS
What triggers a REMS
The FDA requires a REMS when a drug's benefit can only be maintained through specific safety controls. Common triggers: teratogenicity (thalidomide), addiction potential (opioids), serious organ toxicity (clozapine for granulocytopenia), QT prolongation, complex dosing requirements. Around 60 drugs currently have active REMS programs.
REMS components
REMS can include: (1) Medication Guide — patient-facing risk information distributed at dispensing; (2) Communication Plan — sponsor commitment to inform healthcare providers; (3) Elements to Assure Safe Use (ETASU) — restricted distribution networks, prescriber certification, patient enrollment, lab monitoring. ETASU REMS are the strictest. Examples: iPLEDGE for isotretinoin (pregnancy prevention), Thalomid REMS for thalidomide.
Burden + criticism
REMS adds significant friction — prescriber registration, patient enrollment, lab monitoring, restricted pharmacy networks. Critics argue some REMS persist past the point of clinical value, restricting access to needed medications. The FDA periodically reviews and modifies/removes REMS — e.g. mifepristone REMS was significantly modified in 2023.
Shared REMS
For drug classes with similar risks, the FDA can mandate a shared REMS that all sponsors must participate in. The opioid REMS (REMS for IR + ER/LA opioids) is the largest — every sponsor of these drugs participates in the same prescriber education + patient communication system.
FAQ
Are all controlled substances REMS?
No. DEA scheduling and FDA REMS are separate frameworks. Some controlled substances have REMS (opioids), some don't (most benzodiazepines). REMS is about specific safety mitigation; DEA scheduling is about diversion potential.
How is iPLEDGE different from other REMS?
iPLEDGE is one of the strictest REMS — it requires both prescribers and patients to enroll in a central registry, with monthly pregnancy testing for women of reproductive age. The goal is to prevent fetal exposure to isotretinoin.
Can REMS be removed?
Yes — the FDA periodically reviews REMS programs and can remove or modify them if the underlying safety concern is resolved or the program is no longer necessary. Removal requires sponsor application + FDA evaluation.