Clinical trials are carried out by a team of qualified professionals and organizations. These include:

• Principal Investigator (PI): The lead doctor or researcher responsible for running the trial at a specific location
• Study Staff: Nurses, coordinators, and support staff who help with participant care and data collection
• Research Sites: Hospitals, clinics, or private centers where the trial is conducted
• Sponsors: Organizations that fund and oversee the trial (often pharmaceutical companies or research foundations)

Each person or group involved has a specific role, and they must all follow ethical and regulatory guidelines to protect participants.