Overview of Clinical Trials

What Are Early-Phase Clinical Trials

• Early-phase clinical trials begin with the first administration of an investigational drug to humans.
• A key objective of early-phase clinical trials is to characterize the drug's absorption, distribution, metabolism, and excretion during the development period.
• Clinical trials at this development stage are generally not intended for treatment and are conducted in healthy volunteers.
• However, for drugs with serious potential toxicity (e.g., cytotoxic drugs such as anticancer agents), trials are generally conducted in patients.
• To ensure the validity of observations, a randomized and blinded design may also be used.
• Early-phase clinical trials allow assessment of short-term safety and tolerability and provide the pharmacokinetic and pharmacodynamic information as well as the information needed to determine the appropriate dose range and dosing schedule for early therapeutic exploratory trials.

The Four Evaluation Areas of Early-Phase Clinical Trials

Early-phase clinical trials characterize a drug through evaluation of the following four core areas.