Direct comparison
IRB vs. IACUC: Key Differences
IRB reviews human-subjects research under 45 CFR 46; IACUC reviews vertebrate-animal research under the Animal Welfare Act and PHS Policy. Compared.
Side-by-side comparison
| Dimension | IRB | IACUC |
|---|---|---|
| Full name | Institutional Review Board | Institutional Animal Care and Use Committee |
| What it reviews | Research involving living human participants | Research, teaching, or testing involving live vertebrate animals |
| Core governing regulation | The Common Rule, 45 CFR 46 (and 21 CFR Parts 50 & 56 for FDA-regulated research) | Animal Welfare Act (7 U.S.C. 2131-2159, 9 CFR Parts 1-3) plus, for PHS-funded work, PHS Policy |
| Federal enforcement/oversight body | HHS Office for Human Research Protections (OHRP); FDA for regulated products | USDA/APHIS (AWA inspections) and NIH OLAW (PHS Policy Assurance oversight) |
| Minimum committee size | At least 5 members (45 CFR 46.107(a)): varied backgrounds, at least one scientist, one nonscientist, one member unaffiliated with the institution | At least 5 members under PHS Policy IV.A.3 (at least 3 under AWA alone, 9 CFR 2.31): a veterinarian, a practicing scientist experienced with animals, a nonscientist, and an unaffiliated member |
| Species/population excluded | Not applicable — jurisdiction is defined by "human subject" (45 CFR 46.102(e)), not species | AWA excludes purpose-bred rats, mice, and birds and most farm animals raised for food/fiber; PHS Policy closes that gap for PHS-funded work by covering all live vertebrates |
| Pre-review risk/harm test | Risks to subjects are minimized and reasonable in relation to anticipated benefits (45 CFR 46.111); "minimal risk" defined at 46.102(j) | Pain/distress must be minimized; procedures likely to cause pain must be justified and use of alternatives considered (the 3Rs: Replacement, Reduction, Refinement) |
| Review pathways | Exempt, expedited, or full-board review depending on risk level | Designated member review (DMR) or full-committee review (FCR); no exempt category |
| Ongoing oversight after approval | Continuing review (where still required) and reporting of unanticipated problems | Semiannual program review and facility inspection (PHS Policy IV.B), plus post-approval monitoring of active protocols |
| Consent/authorization mechanism | Informed consent from the participant (or legally authorized representative), documented per 46.116-46.117 | No consent analogue — approval runs through the protocol and the institution's animal-welfare Assurance, not the animal |
| Voluntary accreditation available | AAHRPP (Association for the Accreditation of Human Research Protection Programs) | AAALAC International |
| Related administrator credential | Certified IRB Professional (CIP), PRIM&R/CCIP | Certified Professional in IACUC Administration (CPIA), PRIM&R/CCIP |
Common questions
FAQ
Can the same committee handle both human and animal research?+
No. IRB and IACUC are legally distinct committees with different membership requirements, different governing regulations, and different review criteria. An institution running both types of research must convene both committees, even if the same compliance office administers both.
Does a study ever need both IRB and IACUC approval?+
Occasionally, on the same grant or program — for example, a translational project with a human-cohort arm and a separate animal-model arm. The two protocols are still submitted, reviewed, and approved independently; there is no combined IRB/IACUC application.
Is IACUC review required for all animal research?+
It is required for any live-vertebrate-animal research, teaching, or testing conducted at (or under the auspices of) an institution that either uses AWA-covered species or receives PHS funding for the work. Purpose-bred rats, mice, and birds fall outside AWA coverage but are still subject to IACUC review if the work is PHS-funded, because PHS Policy applies to all live vertebrates.
How is IACUC different from IBC?+
IACUC reviews animal welfare in research involving live vertebrate animals. An Institutional Biosafety Committee (IBC) reviews biosafety risk — recombinant/synthetic nucleic acid work, biohazardous agents — regardless of whether animals are involved. See the dedicated IRB vs. IBC comparison for how IBC differs from IRB specifically.
How is IACUC different from AAALAC?+
IACUC is a legally mandated institutional committee that reviews individual protocols. AAALAC International is a voluntary, external accreditation body that periodically evaluates an institution's entire animal-care-and-use program, including how well its IACUC is functioning. See the dedicated AAALAC vs. IACUC comparison for the full breakdown.
Going deeper
