When a trial is terminated or suspended, which parties should be informed promptly and given reasons?

• A. Only the investigators.
• B. Investigators, regulatory authorities, and IRB/IEC, with reasons for termination or suspension as required by law.
• C. Only the sponsor.
• D. Only the regulatory authorities.

Answer: (B)

Prompt, comprehensive communication to oversight bodies is required when a trial is terminated or suspended. The investigator must promptly inform those who oversee the study and can take action to protect participants and ensure compliance: regulatory authorities and the IRB/IEC. Providing the reasons for the termination or suspension, in line with applicable law, allows these bodies to assess safety concerns, determine appropriate regulatory actions, and decide whether the study should continue, be modified, or be stopped permanently. This transparency supports ethical conduct, participant protection, and proper regulatory oversight.

Notifying only one party or excluding an essential oversight group would leave critical safety and ethical review gaps, and omitting the reasons would hinder appropriate assessment and action.