IVD and Diagnostic Agents Regulation in Mexico

1. Key takeaways

Mexico does not set up a separate A to D scale for IVDs. In vitro diagnostic reagents fall legally into the category of diagnostic agents (agentes de diagnóstico), one of the eight categories under Article 262 of the LGS, and their risk classes are still determined within the three-class system of RIS Articles 83 and 83 Bis, applied together with the classification rules of the FEUM supplement. This design has practical consequences at every stage: the classification argument cites general device law rather than a dedicated IVD statute, the evidence depth follows the assigned class rather than an analyte-based letter, and the available pathways — including the simplified pathway — are the device pathways. Teams coming from markets with A to D IVD frameworks need to translate their internal product records into the Mexican vocabulary early, because downstream documents such as fee calculations, dossier structures and holder agreements all key off the Mexican class, not the imported letter.

2. Legal basis

The sources that define and classify diagnostic agents are summarized below.

Notice that no instrument in this table is IVD-specific: the category is defined by the general device law, classified by the general regulation, refined by the general supplement rules and served by the general pathways. That uniformity is the core message of this article.

Uniformity also simplifies portfolio tooling. A single classification template built on the device framework — category, class, supplement rule, annex placement — serves both instruments and reagents, so IVD rows can live in the same regulatory ledger as hardware rows without a parallel schema. The only IVD-specific workstreams are the content ones: calibrator traceability on the label, identity comparison for the simplified pathway, and the intended-use wording that drives the class. Keeping one ledger with IVD-aware columns is lighter to maintain than running two separate processes.

3. Expert insights

Insight 1: The statutory definition of diagnostic agents is broad. Under LGS Article 262, diagnostic agents include antigens, calibrators, verification or quality control antibodies, reagents, reagent equipment, culture media and contrast media, together with any other similar products that can be used in clinical or auxiliary clinical operations. A definition this wide means that the boundary of the category is narrowed in practice by intended use, not by the statute. A substance that could serve a clinical purpose is captured only when it is actually placed on the market for that purpose. Companies should therefore describe intended use precisely in every regulatory document, because the wording is what pulls a borderline product into or out of the category.

Insight 2: Classification does not set a separate tier by analyte risk. Unlike markets that give IVDs a dedicated A to D scale, Mexico places IVDs in the unified three-class system. The same reagent can land in different classes depending on its intended use — screening, diagnosis or companion diagnosis — because the class criteria look at how the result is used rather than at the analyte as such. A portfolio manager cannot therefore assign one class per product family; each intended use statement needs its own class determination, and changes in intended use are classification events that should trigger re-analysis.

Insight 3: The simplified pathway is open to IVDs. The simplified pathway guidelines published in DOF 2025-07-18 cover medical devices, and diagnostic agents are included. The precondition is that the product is identical to the version approved by the reference regulatory authority, and that the reference approval was obtained no more than 5 years ago. The identity condition deserves attention: even minor formulation or claim differences can break it, so the comparison between the reference approval and the Mexican application should be documented in the dossier rather than asserted.

Insight 4: Labeling has specific requirements for diagnostic agents. NOM-137-SSA1-2025 requires diagnostic agents to state calibrator values assigned and the traceability information of the materials used for calibration verification; such information was not mandatory under the previous edition of the standard. Laboratories and distributors will increasingly expect this traceability on the label, so planning the label update alongside the regulatory timeline is more efficient than treating it as a separate commercial decision.

Insight 5: The low-risk lists contain IVD-relevant items. Annexes I and II of the 2025 agreement include some laboratory supplies, and Annex III excludes a group of laboratory reagents from the definition of health supplies. IVD products should check the lists before choosing a registration path, because the annex placement can eliminate the registration obligation entirely or place the product on the fast Annex I track.

4. Practical recommendations

1. In the IVD classification argument, state the assignment to the diagnostic agents category under LGS Article 262 first, and only then descend to the three-class level.
2. The more specific the intended use statement, the more stable the class determination; keep screening and confirmatory diagnosis wording clearly distinct.
3. For the simplified pathway, first verify that the reference approval was obtained within 5 years.
4. Supplement calibrator values and material traceability information in line with NOM-137-SSA1-2025, and fold the change into the label revision plan.
5. Check Annex III of the 2025 agreement first to confirm whether the product is excluded from the definition of health supplies altogether.

5. Verification checklist

• □ Confirmed assignment to the diagnostic agents category of LGS Article 262
• □ Three-class level determined under RIS Articles 83 and 83 Bis
• □ No A to D scale applied
• □ Reference approval for the simplified pathway obtained within 5 years
• □ Label traceability information supplemented under NOM-137-SSA1-2025
• □ Annex placement under the 2025 agreement verified

Regulatory information verified as of October 28, 2026.

How GRZAN can help. GRZAN provides medical device and IVD registration, quality system, authorised representative and local testing support for the Mexican market. Our team manages COFEPRIS registrations and equivalence (equivalencia) reviews, coordinates third-party authorised centre routes, and supports post-market vigilance obligations. Business enquiries: info@grzanglobal.com