Your approval letter will clarify how long the study is approved — typically 1 year [see 45 CFR 46.109(d) (DHHS) and 21 CFR 56.109(d) (FDA)]. You must submit a continuing review before your study expires if you wish to continue the research.
Exempt Research: There are no expiration dates for studies that the IRB certifies as exempt. Continuing review is not required.
For initial reviews and continuing reviews, the expiration date will be 1 year (minus 1 day) from the approval date.
At UCSF the approval date is the day when study activities involving human subjects may start; the expiration date is the last day on which activities may continue, unless a new approval is given.
Federal regulations require that (1) except when an expedited review procedure is used, each IRB must review proposed research at convened meetings at which a majority of the members of the IRB are present, including at least one member whose primary concerns are in nonscientific areas; and (2) an IRB must conduct continuing review of research at intervals appropriate to the degree of risk, but not less frequently than once per year. The IRB should decide the frequency of continuing review for each study protocol necessary to ensure the continued protection of the rights and welfare of research subjects.