What is the primary goal of a Phase I clinical trial?

The primary goal of a Phase I clinical trial is to determine the safest dosage range of a new drug. During this phase, a small group of healthy volunteers or patients is exposed to the drug to evaluate its safety, tolerability, pharmacokinetics (the way the drug is absorbed, distributed, metabolized, and excreted in the body), and pharmacodynamics (the effects of the drug on the body). This information is crucial for establishing the appropriate dosage for subsequent phases of clinical trials, where the focus will shift to assessing the drug's efficacy and further understanding its safety profile.

In earlier phases of drug development, much emphasis is placed on understanding the drug's interaction with the human body at various dosages before determining how well it works (efficacy) or how it performs in comparison to existing treatments. Evaluating long-term effects also falls outside the scope of Phase I trials, as these trials primarily focus on immediate safety data rather than prolonged outcomes. Therefore, determining the safest dosage range is a vital step in the drug development process that lays the foundation for future research.