As of January 20, 2020, federally funded cooperative (multi-site) research projects involving human subjects must seek approval by a single Institutional Review Board (IRB). This mandate is broader than the single-IRB mandate that went into effect January 2018 for NIH-funded studies.
The reviewing IRB will be identified by the federal agency funding the research or proposed by the lead institution, subject to approval by the federal agency.
Note that each institution is still responsible for safeguarding its subjects' rights and welfare. For example, other types of reviews either mandated by other regulations or by institutional policy, e.g., biosafety, environmental health and safety, and conflicts of interest, must be obtained in addition to the required central review.
For more information, please contact the IRB at email@example.com