Final answer:
Extensive preclinical testing and FDA approval through an IND application are prerequisites before a new drug can be used in humans. Clinical trials then assess the drug's safety and efficacy, followed by post-approval monitoring for long-term safety. Pharmacokinetics affected by various factors are also scrutinized.
Step-by-step explanation:
Before putting a new drug in humans, extensive preclinical testing is conducted. This includes laboratory research and animal trials to collect substantial data on the drug's toxicity, pharmacokinetics, and initial evidence of efficacy. Once this data is gathered, researchers submit an Investigational New Drug (IND) application to the FDA's Center for Drug Evaluation and Research (CDER). A 30-day review period follows, after which, if no major issues are raised by the FDA, clinical trials with human subjects can proceed.
During clinical trials, the new drug is evaluated across multiple phases to determine its safety, efficacy, dosing, and observe any adverse reactions. Post-approval, the drug is still monitored through pharmacovigilance systems to ensure its long-term safety and effectiveness in the general population. Additionally, factors like age, gender, genetic characteristics, and interactions with food can influence drug pharmacokinetics, and are also evaluated during clinical trials.