Under the Controlled Substances Act (CSA) in the United States, drugs that have the potential to be abused are scheduled into one of five Classes or Schedules (CI-V) as controlled substances. The scheduling method makes a distinction between drugs that have abuse potential and are not approved for medical use (i.e., Schedule I) and drugs that are approved for medical use and have abuse potential (Schedules II-V). In the classification, the higher the number of the Schedule, the lower the abuse potential of the drug and the less restrictive the conditions regarding its distribution, storage, and prescribing.

Schedule I, or Class I (CI), drugs are currently restricted to research in the U.S., meaning that they are not approved for medical use, and are deemed at highest risk for abuse.

Recent research on psychedelics and entactogens, both of which are Schedule I, is beginning to demonstrate the potential therapeutic effects of these drugs for various medical indications. Approvals of such drugs for medical or therapeutic use will inevitably result in the rescheduling of these drugs from their current CI status.

In Issue 19 of The Altascientist, we review:

• the regulatory environment and challenges (Drug Enforcement Administration
• the research site requirements associated with the development of Schedule I drugs for therapeutic 
• required preclinical studies of Schedule I drugs
• required clinical studies of Schedule I drugs
• specialized clinical assessments of Schedule I controlled substances
• formulation, manufacturing, and analytical considerations for Schedule I drugs