Investigators are required to report promptly to the sponsor any adverse effect that may reasonably be regarded as caused by, or probably caused by, the drug. If the adverse effect is alarming, the investigator shall report the adverse effect immediately. serious adverse events should be reported to the IRB within one week of the investigator becoming aware of the event. Any other unanticipated problem should be reported to the IRB within 2 weeks of the investigator becoming aware of the problem.