Phase I – In this phase, between 20-80 volunteers who are healthy (and do not have the condition the drug is intended to treat) will help to determine the safety of the product. The drug sponsor will look for potentially harmful side effects as well as to see how human bodies react to the drug.
Phase II – Hundreds of patients are involved in drug testing in this phase. Many of them will have the condition that the drug aims to treat. At this second phase, the drug sponsor seeks to determine the effectiveness of the product.
Phase III – Thousands of patients will be involved in testing the drug when it reaches the third phase. The drug sponsor will look to determine both safety and effectiveness and draw conclusions about dosages, drug interactions and patient populations.4. New Drug Application (NDA). Once the clinical trials are completed, the next step is for the drug sponsor to meet with the FDA before an NDA is submitted. The drug sponsor will formally ask the FDA to approve the drug based on the data from clinical trials and testing. 5. FDA review. The FDA will have a total of 60 days to decide whether to file the NDA and review the request for FDA approval. If the FDA files the application, it will then assign a review team made up of physicians, statisticians, chemists, pharmacologists and others to examine the drug sponsor’s data. The review team specifically will assess the safety and effectiveness of the drug. 6. Labeling review. In this stage, the FDA will review the labeling for the drug to ensure that it provides accurate information to consumers and to health care professionals about the medication and how to safely use it. 7. Facility inspection. Before approval, the FDA will inspect the manufacturing facility for the drug. 8. Approval or rejection. Once all of the above steps have been completed in a satisfactory manner, the FDA can approve the drug for use or reject it. If the FDA does not approve it, the agency can issue a response letter. 9. Post-marketing monitoring. Even after a drug is approved, this is not the end of the FDA’s involvement. The FDA has a post-marketing safety system that continues to review the drug and to keep track of adverse events.