The process of clinical trials usually begins in a lab where new ideas are developed with a view to develop better drugs with high efficacy and safety. Clinical trials are scientific studies conducted to find better ways to prevent, screen, diagnose, or treat disease Clinical trials use strict scientific standards to ensure that there is no harm to patients .
Clinical trials are categorized into 4 phases & Each phase has a different reason.
These 4 phases can be described as follows:
Phase I: These trials test an investigational drug in a very small group of people to evaluate safety & possible side effects of the drug.
Phase II: These trials involve larger sample of population than phase I and they are conducted to measure the safety and efficacy of an investigational treatment. This phase usually last for several years.
Phase III: Large studies with more participants are conducted to compare the investigational drug to a specific treatment for evaluating its safety and efficacy. Some side effects that were not identified in earlier phase may be identified in this Phase.
Phase IV: This phase takes place when the use of the drug has been approved by a regulatory health authority, i.e. US Food & Drug Administration (USFDA), European Medicines Evaluation Agency (EMEA) or Central Drugs Standard Control Organisation (CDSCO) etc. The efficiency & safety of the particular drug is observed & checked in very large & diverse population.
Chemxpert provides information for the clinical trials of various countries as under:
For example. Clinical trial data for paracetamol