Clinical Trial Phases Practice Test

A 22-year-old man (75 kg) is a healthy volunteer in a Phase I trial of SEDATOL, a new oral anxiolytic. The trial uses ascending doses and measures sedation scores, respiratory rate, and plasma concentrations; baseline creatinine is 0.8 mg/dL. He signs informed consent after being told not to drive and that he can stop participation at any time. What is the primary goal of this Phase I clinical trial?

A 64-year-old woman (66 kg) with osteoporosis is screened for a Phase III trial of OSTEO-BUILD, a new monthly injection. The trial randomizes patients to OSTEO-BUILD versus alendronate for 24 months; the primary endpoint is incidence of new vertebral fractures, and safety monitoring includes serum calcium (baseline 9.3 mg/dL). She signs informed consent after discussion of randomization and potential adverse effects. What distinguishes this Phase III trial from other phases?