IVD — In Vitro Diagnostic Products

An IVD is an in vitro diagnostic product. Under 21 CFR 809.3(a), the US definition covers reagents, instruments and systems intended for diagnosing disease or other conditions, including determining the state of health, in order to cure, mitigate, treat or prevent disease or its sequelae. These products are intended for the collection, preparation and examination of specimens taken from the human body. (§809.3(a))

That wording matters in two ways. First, the definition reaches beyond the instrument or reagent that performs the final examination: collection and preparation are expressly included. Second, intended use is part of the definition. Merely describing an item as laboratory equipment does not answer whether its intended purpose meets the regulatory wording.

Section 809.3(a) identifies these products as devices under section 201(h) of the Federal Food, Drug, and Cosmetic Act and states that they may also be biological products subject to section 351 of the Public Health Service Act. Device status and potential biological-product status are therefore not mutually exclusive in this definition.

As a practical starting point, write down what the product is intended to do and its role in handling human specimens before assigning a regulatory shorthand. Keep the definition question separate from the later applicability questions discussed below.

Research Use Only (RUO) and Investigational Use Only (IUO) are not all-law exemptions. Section 809.10(c) provides conditional exemptions for a shipment or delivery from §809.10(a) and (b), and from a standard promulgated under Part 861. One branch concerns investigations subject to Part 812 and requires compliance with that part. A separate branch addresses investigations not subject to Part 812 and contains the research-stage and product-testing conditions below. (§809.10(c)))

The required statements are precise: “For Research Use Only. Not for use in diagnostic procedures.” and “For Investigational Use Only. The performance characteristics of this product have not been established.” An RUO or IUO label alone therefore does not settle every intended-use question.

The general-laboratory provision is different. Section 809.10(d) permits reduced directions for qualifying products, but reagent labels still need the information listed in paragraph (d)(1). General-purpose equipment labels must adequately describe the product and include its composition and physical characteristics when necessary for proper use. Reduced directions do not mean a blank label.

The Laboratory Developed Tests (LDT) rule history needs dates, not an active phase-out calendar. On 6 May 2024, FDA issued a final rule adding “including when the manufacturer of these products is a laboratory” to the IVD definition. On 31 March 2025, a federal district court vacated that rule. (FDA LDT status)

FDA then issued a reverting rule, published at 90 FR 45134–45136 and effective on 19 September 2025. It removed the added words and restored the regulatory text that existed before the 2024 rule took effect. The current §809.3(a) definition retains the statement that the products are devices and may also be biological products.

For recordkeeping, distinguish a historical description of the 2024 rule from a statement of current requirements. A dated source and a clear status note are more useful than carrying forward obsolete milestone dates.

The Clinical Laboratory Improvement Amendments (CLIA) framework concerns laboratory oversight and testing complexity. FDA's explanatory CLIA overview describes three participating federal agencies with different responsibilities. That overview is nonbinding explanatory material; the legal test-category and certificate provisions discussed here are in 42 CFR 493.5. (FDA CLIA roles)

Under 42 CFR 493.5, tests fall into three categories: waived tests; moderate-complexity tests, including the subcategory of PPM procedures; and high-complexity tests. The regulation separately requires each laboratory to be CLIA-exempt or to possess one of the listed CLIA certificates. A waived test and a certificate of waiver are related concepts, but one describes a test category and the other a laboratory certificate.

FDA's categorization page explains that categorization is determined after FDA has cleared or approved a marketing submission, or upon request for legally marketed devices. Keep the product's regulatory status, its CLIA category and the laboratory's certificate in separate fields when reviewing documentation. None should be used as shorthand for the others.

The Quality Management System Regulation (QMSR) in 21 CFR Part 820 has its own applicability boundary. Section 820.1 addresses finished devices intended for human use, including finished devices manufactured in the specified US jurisdictions or imported or offered for import into the United States. Its scope covers activities such as design, manufacture, packaging, labeling, storage, installation and servicing. (§820.1)

A manufacturer engaged in only some covered operations need comply only with requirements applicable to the operations it performs. Section 820.1(a)(2) also expressly excludes manufacturers of components or parts of finished devices from Part 820, while encouraging them to consider appropriate provisions. That is a Part 820 boundary, not a blanket exemption from every other requirement.

For a manufacturer within scope, §820.10 requires a documented quality management system complying with the applicable requirements of ISO 13485, incorporated by reference under §820.7, and the other applicable requirements of Part 820. This definition article does not expand that reference into a clause-by-clause account of the standard.

Applicability still needs its qualifications. Section 820.1 contains specific exclusions, gives device-specific requirements priority over more general requirements in a conflict, and provides a procedure to petition for an exemption or variance. A practical review should identify the product role and performed operations rather than assuming that every supplier connected to an IVD has identical obligations.

For products subject to the ordinary IVD label requirements, §809.10(a) specifies content subject to applicability qualifications and stated exceptions. The intended use is one required item. For reagents, the provision also addresses appropriate storage instructions, including instructions for a reconstituted or mixed product stored in its original container. (§809.10(a)))

Assurance at the Time of Use

Section 809.10(a)(6) requires a means of assuring the user that a reagent meets appropriate standards of identity, strength, quality and purity at the time of use. For both the product as supplied and any resultant reconstituted or mixed product, the label must include one or more of three means: an expiration date based on stated storage instructions; an observable indication of alteration beyond appropriate standards; or instructions for a simple method of determining whether the product meets its standards. An expiration date is therefore not the sole option imposed by this paragraph.

Lot or Control Identification

Section 809.10(a)(9) requires an identified lot or control number from which the complete manufacturing history can be determined. The number is not merely a convenient stock identifier. Three product-form qualifications accompany the requirement:

• For a multiple-unit product, the number must permit tracing the identity of the individual units.
• For an instrument, the number must permit tracing the identity of all functional subassemblies.
• For multiple-unit products whose included units must be used together as a system, all units should bear the same lot or control number, if appropriate, or other suitable uniform identification should be used.

Separate QMSR Record Obligations

Within the applicable QMSR scope, §820.35(c) requires the UDI to be recorded for each medical device or batch of medical devices. Section 820.45 addresses a different subject: labeling and packaging controls. It requires documented procedures, examination for accuracy before release or storage where applicable, documentation of labeling release for use, and documentation of labeling-inspection results. These provisions should not be collapsed into a single claim that §820.45 universally requires final-product release documentation.

The EU definition is a separate legal test. Article 1 of Regulation (EU) 2017/746 addresses placing on the market, making available and putting into service human-use IVD medical devices and their accessories in the Union. Article 2(2) ties the definition to the manufacturer's intended purpose for in vitro examination of human-derived specimens, including blood and tissue donations, solely or principally to provide specified information. (IVDR Articles 1 and 2)

Those purposes cover physiological or pathological processes or states, congenital impairments, predisposition to disease, safety and compatibility with potential recipients, prediction of treatment response or reactions, and defining or monitoring therapeutic measures. Specimen receptacles are also deemed IVD medical devices.

Article 1 excludes general-laboratory and research-use-only products unless, in view of their characteristics, their manufacturer specifically intends them for in vitro diagnostic examination. It also excludes invasive sampling products and products directly applied to the body to obtain a specimen. Do not transfer the US definition's collection wording into the EU framework without checking these boundaries.

A useful organizational approach is to retain the basis for each conclusion rather than a single “IVD compliant” status. The following map is a practice recommendation for keeping distinct legal concepts visible; it is not a prescribed record format or an additional regulatory requirement.

For a concise desk review, retain the source and date supporting the intended-use conclusion, any RUO or IUO labeling condition, and the relevant QMSR applicability decision. Where laboratory testing is involved, keep the test category and laboratory certificate separately identifiable. Mark historical LDT material as historical rather than allowing an old schedule to appear current.

The aim is a record that explains which question was answered and which remains open. A label statement, a lot number, a laboratory certificate and a UDI record can all be relevant without being interchangeable evidence.