Investigator-Initiated Trials: FDA & GCP Rules

An investigator-initiated trial (IIT) — also called an investigator-initiated study (IIS) — is a clinical investigation designed, sponsored, and conducted by an individual investigator rather than a pharmaceutical or device company. Under 21 CFR 312.3, this individual is a sponsor-investigator: someone who both initiates and actually conducts the study, and under whose immediate direction the investigational drug is administered or dispensed. The parallel device definition, 21 CFR 812.3, is worded almost identically. In both cases, only an individual — not an institution or company — can hold the sponsor-investigator role.

That dual identity is the whole administrative challenge of an IIT. A sponsor-investigator does not get a reduced or merged set of obligations for holding both roles — they must independently satisfy the full sponsor responsibilities and the full investigator responsibilities set out in 21 CFR Part 312, Subpart D. This guide walks through what that means in practice: when an IND is required, what the sponsor-side obligations look like, what the investigator-side obligations look like, the paperwork that anchors both, and where institutional support (a clinical trials office, a CRO, or a sponsor-supplied drug) fits in without changing who is legally accountable.

Sponsor-investigator vs. a site in an industry-sponsored trial

The distinction that matters is not funding source — it’s who holds the IND or IDE. A study can remain investigator-initiated even when a pharmaceutical company donates drug supply or provides a research grant, as long as the company has not taken over IND/IDE sponsorship. Once a company accepts sponsor responsibilities for the study (files or holds the IND, assumes 312.50-series obligations), the investigator is a site participating in a company-sponsored trial, not a sponsor-investigator — even if the trial idea originated with that investigator.

Does the study need an IND or IDE at all?

Not every investigator-led study of a drug requires a new IND. 21 CFR 312.2(b) exempts a clinical investigation of an already lawfully marketed US drug from IND requirements, but only if every one of the following conditions holds — it is a conjunctive test, and failing any single condition means a full IND is required:

The study is not intended to support a new indication for use, or a significant change in the product’s approved labeling or advertising.
It does not involve a route of administration, dose, patient population, or other factor that significantly increases the risk (or decreases the acceptability of risk) associated with the approved use.
It is conducted in compliance with IRB review (21 CFR Part 56) and informed consent (21 CFR Part 50).
It is not intended to promote or commercialize the drug for an unapproved use, per 21 CFR 312.7.
The drug is in fact lawfully marketed in the United States.

See the full breakdown at IND exemption under 21 CFR 312.2(b). Investigators frequently assume that because a drug is FDA-approved, no IND is needed for any research use of it — that assumption fails as soon as the study tests a new population, route, or dose, or is powered toward a labeling claim. When an IND is required, the IND application itself must include, among other components, an outline of the investigational plan and adequate information about the drug’s pharmacology and toxicology (21 CFR 312.23) — the same core requirements that apply to a company-sponsored IND, just assembled and submitted by the investigator instead of a sponsor company. Many institutions require investigators contemplating a new IND to request an FDA pre-IND meeting before submission, and the FDA Form 1571 cover sheet is the administrative document that accompanies the IND submission itself.

Sponsor-side obligations (21 CFR Part 312, Subpart D)

Once an IND is in place, the sponsor-investigator must satisfy the same sponsor-responsibility sections a pharmaceutical company sponsor would, including:

312.50 — general responsibilities of sponsors (ensuring the investigation is conducted according to the general investigational plan and protocols, and monitored appropriately).
312.52 — transfer of sponsor obligations to a contract research organization (CRO), if any obligations are formally delegated.
312.53 — selecting qualified investigators and monitors (largely self-referential for a sponsor-investigator, but still requires documenting the qualifications on which selection rests).
312.55 — informing investigators (again largely self-directed, but relevant if the study has subinvestigators or additional sites).
312.56 — reviewing the ongoing investigation and acting on evidence of unacceptable risk.
312.57 — sponsor-side recordkeeping and record retention.
312.58 — making sponsor records available for FDA inspection.
312.59 — disposition of unused investigational drug supply.
312.32 — IND safety reporting: reporting unexpected fatal or life-threatening suspected adverse reactions to FDA within 7 calendar days of the sponsor becoming aware (with a complete follow-up report within an additional 8 days), and other serious, unexpected suspected adverse reactions within 15 calendar days.

Investigator-side obligations (21 CFR Part 312, Subpart D)

In parallel, the same individual must independently satisfy the investigator-responsibility sections:

312.60 — general responsibilities of investigators: ensuring the investigation is conducted according to the signed investigator statement, the investigational plan, and applicable regulations; protecting the rights, safety, and welfare of subjects; and controlling the investigational drug.
312.61 — control of the investigational drug (dispensing only to subjects under the investigation, per protocol).
312.62 — investigator recordkeeping: maintaining adequate disposition records for the investigational drug (dates, quantities, subject use), and retaining records for two years following marketing-application approval for the studied indication — or, if no application is approved, until two years after the investigation is discontinued and FDA is notified.
312.64 — investigator-to-sponsor reporting: reporting any serious adverse event to the sponsor immediately, regardless of the investigator’s own causality assessment, with a causality opinion included; non-serious adverse events follow the protocol’s specified reporting schedule instead. For a sponsor-investigator, this obligation is effectively self-directed — the same individual receiving the report as the sponsor also generates it as the investigator — but it still must be documented as occurring, not skipped because the two roles are held by one person.
312.66 — assurance of IRB review: promptly reporting to the IRB all changes in research activity and all unanticipated problems involving risk to subjects, and not making changes without IRB approval except where necessary to eliminate an apparent immediate hazard.
312.68 — making investigator records available for FDA inspection.
312.69 — special recordkeeping and disposition requirements when the investigational drug is a controlled substance.
312.70 — FDA’s authority to disqualify a clinical investigator found to have repeatedly or deliberately violated these regulations, or submitted false information to the sponsor.

There is no shortcut here: a sponsor-investigator who is disorganized on the sponsor side (late safety reporting, no documented drug-disposition oversight) is exposed under 312.50-series citations even if their bedside conduct of the trial is impeccable, and vice versa.

Foundational paperwork: Form 1572 and the delegation log

Two documents anchor day-to-day compliance regardless of which side of the sponsor-investigator split is being assessed.

FDA Form 1572 (Statement of Investigator) is the signed pre-trial document required under 21 CFR 312.53 before an investigator begins participating in an IND-regulated investigation. It captures the investigator’s name and facility, the applicable IRB, subinvestigator names, and — in its Commitments section — the investigator’s affirmation to conduct the study per protocol, ensure informed consent and IRB review, report adverse events, and maintain adequate records. For a sponsor-investigator’s own IND, institutional practice on whether a 1572 must formally be filed varies; treat this as an institutional-policy question to confirm locally rather than a uniform rule, and default to completing one regardless, since it conveniently documents the same qualifications and commitments information 21 CFR 312.23(a)(6)(iii)(b) requires the IND itself to contain.

Delegation of Authority (DoA) log is the continuously maintained, task-level record required by ICH E6(R2) Section 4.1.5, listing every staff member to whom significant trial-related duties have been delegated, with per-task start and end dates. It is a distinct document from Form 1572 — the 1572 is a single signed statement naming the PI and subinvestigators, amended only for defined triggering events (a new protocol under the same IND, a new PI); the DoA log covers every delegated team member, not just subinvestigators, and is updated continuously. Delegating a task transfers its performance, never the sponsor-investigator’s underlying regulatory responsibility for the trial’s conduct.

GCP obligations layered on top of FDA regulations

ICH E6(R2) Good Clinical Practice guidelines apply alongside — not instead of — the FDA regulations above, and most academic medical centers require documented GCP certification for anyone in an investigator or delegated role on an IIT. Where GCP diverges from a strict regulatory reading, it tends to be more operationally specific: 4.1.5 (delegation) and the sponsor safety-evaluation expectations in Sections 5.16-5.18 both fill in process detail that Part 312 states only at the level of an outcome requirement. Treat FDA regulations as the binding legal floor and ICH E6(R2) as the operational standard institutions and IRBs will expect to see documented on top of it.

Where institutional infrastructure fits without shifting accountability

Most academic sponsor-investigators do not run an IIT alone. A clinical trials unit, institutional CTMS, or a contracted CRO can absorb real operational load — safety-report tracking, monitoring visits, drug accountability logs, data management — and 312.52 explicitly contemplates transferring specific sponsor obligations to a CRO in writing. What none of that changes is who FDA holds accountable: transferred obligations must be documented (which tasks, to whom, effective when), and any obligation not explicitly transferred in writing remains the sponsor-investigator’s. The same logic that governs the DoA log at the investigator level applies at the institutional level — delegation moves performance, not responsibility.

A Data Safety Monitoring Board and prospective trial registration (e.g., ClinicalTrials.gov, required for applicable clinical trials under FDAAA 801 and 42 CFR Part 11) are separate obligations worth planning for early, since both have their own lead times and are commonly requested by IRBs or journals as a condition of review or publication, independent of the IND/IDE requirements above.

Frequently asked questions

Who counts as the sponsor-investigator on a multi-site IIT?

Only one individual can hold the sponsor role for a given IND or IDE. On a multi-site IIT where the originating investigator holds the IND, other-site investigators are treated as investigator-only participants under that IND — they take on the investigator-side obligations (312.60-312.70) at their own site but not the sponsor-side obligations, which remain with the individual who holds the IND.

Does using company-donated drug supply make a study company-sponsored?

Not by itself. The determining fact is who holds IND/IDE sponsorship, not the source of funding or drug supply. A company can donate product or provide a research grant to an investigator-initiated study without becoming the sponsor, as long as it has not taken over the sponsor-side regulatory role.

What happens if the sponsor-side and investigator-side obligations conflict on timing, given one person holds both roles?

They don’t get merged or relaxed — each set of obligations is evaluated independently. In practice this means, for example, that a serious adverse event must still be documented as reported by the investigator to the sponsor (312.64) and evaluated by the sponsor for IND safety reporting (312.32), even though the same person performs both steps, because FDA inspection and audit both sides of that paper trail separately.

Is Form 1572 required when the investigator is also the sponsor?

Institutional practice varies on whether this is a strict independent regulatory requirement in every case; check local institutional policy. Completing one regardless is common practice because it captures information the IND application itself is required to contain.