Points to Consider for the Evaluation of the Effects of Food on the Pharmacokinetics of Oral Drug Products — PMDA Early Consideration Summary

In Plain Language

Food can change how a medicine taken by mouth is absorbed, which may change the amount or timing of drug in the body. This document considers when a food-effect study done with a formulation still under development may provide enough information, rather than requiring another study with the final formulation. It says that when bioequivalence—a finding that two formulations have sufficiently similar drug exposure—has been demonstrated, differences in their food effects are considered limited. For immediate-release products containing a drug substance with high solubility and high permeability, the document discusses a possible approach when food does not affect overall exposure, measured by area under the concentration–time curve (AUC). However, food may still affect the maximum concentration (Cmax), so the importance of Cmax to efficacy and safety matters. The aim is to help developers assess food effects while paying attention to the particular formulation and the pharmacokinetic measure that matters for the drug.

What This Guidance Covers

The document addresses evaluation of the effects of food on the pharmacokinetics of oral drug products. Its particular focus is whether food-effect (FE) study results from a formulation other than the final formulation can inform assessment of the final product. A food-effect study examines how taking a drug with food, rather than under the study’s comparison condition, affects its pharmacokinetic profile.

The document describes “final formulation” by reference to a Japanese notification on clinical pharmacokinetic studies: it is a formulation with the same composition as the marketed product and manufactured using the same process at a scale of not less than one-tenth of the actual commercial production lot. The document’s considerations are about whether a study using a formulation under development may make an additional FE study with this final formulation unnecessary in specified circumstances.

The points concern oral products, with one set specifically limited to immediate-release drug products containing drug substances with high solubility and high permeability. The document does not present its formulation-based consideration as a general waiver for all oral products. Nor does it describe a single numerical decision rule for all drug products: the proposed conclusions depend on bioequivalence, product characteristics, observed AUC effects, and whether Cmax is important for efficacy and safety.

Why It Matters

The document explains that absorption from the gastrointestinal tract may be affected by the presence or composition of food. Understanding that effect helps establish the drug’s pharmacokinetic profile and appropriately determine its dosage regimen. Food may influence the amount absorbed, the concentration reached, or both, so a developer needs to understand which effects occur for the product being developed.

The background is a practical gap in how to evaluate food effects when development studies use a formulation that is not the final one. The document notes that the Japanese notification on clinical pharmacokinetic studies states that food effects on gastrointestinal absorption should be evaluated using the final formulation. It also notes that studies have been conducted in Japan using other formulations, while no document had explicitly described the considerations underlying those approaches. This Early Consideration sets out points for assessing when such evidence may be informative.

The document also responds to a distinction between overall exposure and peak concentration. Its discussion of survey information says that food effects on AUC had not been observed for the specified immediate-release products with high solubility and high permeability, while effects on Cmax had been observed for multiple products. Thus, a conclusion about AUC does not automatically settle the question about Cmax. That difference is especially relevant if Cmax is considered important for the drug’s efficacy or safety.

Key Recommendations

1. Consider whether the study formulation is bioequivalent to the final formulation. The document states that, when bioequivalence has been demonstrated between different formulations, differences in the magnitude of their food effects on gastrointestinal absorption are considered limited. If an FE study uses a formulation under development, and it can be adequately explained that this formulation is bioequivalent to the final formulation, conducting an additional FE study with the final formulation is generally considered unnecessary.

2. For certain immediate-release products, consider AUC findings alongside Cmax. The document cites surveys of previously approved products in Japan reporting no food effects on AUC for immediate-release products containing drug substances with high solubility and high permeability. If an FE study with a product under development in this category indicates no food effect on AUC, the document says it can be inferred that food will also have no effect on AUC for the final formulation.

   This AUC consideration does not, by itself, resolve the question of peak concentration. The document notes that food effects on Cmax have been observed for multiple products in this category, suggesting that Cmax effects may differ between the formulation studied during development and the final formulation. For a drug for which Cmax is considered important for efficacy and safety, the effects of food on the final formulation should be carefully evaluated.

3. Consider the stated combination of conditions before deciding that another study is unnecessary. The document says that it may be determined that an additional FE study with the final formulation is unnecessary if all three conditions below are met:

   • The product is an immediate-release drug product containing a drug substance with high solubility and high permeability.
   • It can be justified that Cmax is not critical for the efficacy and safety of the drug.
   • No effects of food on AUC are observed in the FE study conducted using the formulation under development.

   The document encourages sponsors to use PMDA consultation services as appropriate to confirm the appropriateness of such evaluations.

Practical Implications

Interpretation: The document gives developers a way to organize the evidence when the FE study did not use the final formulation. It does not say that using a development formulation automatically makes another study unnecessary. The sponsor needs to explain why the study formulation is relevant to the final one, and the discussion of bioequivalence is one route the document identifies.

For the immediate-release category, the conditions operate together. A finding of no food effect on AUC in the development formulation is not enough on its own: the product must also have the stated solubility and permeability characteristics, and the sponsor must be able to justify that Cmax is not critical for efficacy and safety. If Cmax is important, the document emphasizes careful evaluation of food effects on the final formulation, even where the AUC result appears reassuring.

For statisticians and clinical pharmacologists, this means keeping the endpoints distinct in study interpretation. AUC describes overall exposure across time, while Cmax describes the maximum concentration; evidence about one should not be presented as if it establishes the other. For clinical operations and formulation teams, the final formulation’s composition and manufacturing process matter because they are part of the document’s definition of the final formulation. Regulatory and medical-writing teams can make the rationale transparent by identifying the study formulation, describing the basis for bioequivalence where used, and addressing AUC and Cmax separately.

These are practical interpretations of the document’s points, not additional PMDA requirements. The document specifically encourages consultation with PMDA as appropriate when confirming whether an evaluation using a non-final formulation is appropriate.

Technical Details

The document’s key technical distinction is between formulation comparison and food-effect assessment. Bioequivalence is considered between different formulations; the FE study then evaluates the effect of food on pharmacokinetics for the formulation used in that study. The document does not specify in this text a bioequivalence margin, statistical procedure, sample-size method, or study design. It asks that bioequivalence to the final formulation be adequately explained when relying on the formulation-comparison approach.

For the immediate-release discussion, the document relies on survey definitions and findings. In the cited survey described in Reference 4, high solubility means that the highest single therapeutic dose is completely soluble in 250 mL or less of aqueous media at pH values around 1.2, 4.5, and 6.8, regardless of aqueous-medium temperature. The document’s note defines high permeability for that reference as absolute bioavailability of at least 0.85, or recovery in urine of at least 0.85 of the administered dose as unchanged parent drug or as the sum of parent drug and phase 1 oxidative and phase 2 conjugative metabolites. For metabolites in feces, only oxidative and conjugative metabolites were considered. The document also says that Reference 5 determined high solubility and high permeability with reference to the Biopharmaceutics Classification System (BCS) classification.

The document gives absolute bioavailability of 85% or greater as an example associated with high permeability in its discussion of products under development. That example should be read alongside the cited definitions rather than as a substitute for the full conditions the document lists for deciding whether another FE study may be unnecessary.

In everyday terms, a reassuring result for total exposure does not necessarily guarantee the same result for the peak concentration. The document therefore treats the role of Cmax in efficacy and safety as a key part of deciding whether the AUC evidence can support not conducting an additional final-formulation study.

Who Should Read It

This document is relevant to sponsors developing oral drug products, especially teams deciding whether a food-effect study performed before the final formulation can support assessment of that final product. Clinical pharmacologists and biostatisticians may find its distinction between AUC and Cmax useful when framing study objectives and interpreting results. Formulation scientists and pharmaceutical development teams may use it to understand why formulation comparability matters. Regulatory affairs professionals, medical writers, and clinical operations teams may find it helpful when explaining the rationale for the study formulation and any proposal not to conduct an additional study. The document also identifies PMDA consultation as an appropriate option for confirming the appropriateness of such evaluations.

Official PMDA Source

• Official title: Points to Consider for the Evaluation of the Effects of Food on the Pharmacokinetics of Oral Drug Products (Early Consideration)
• Issuing body: Pharmaceuticals and Medical Devices Agency, Center for Product Evaluation
• Date on the document: March 30, 2026
• PMDA PDF: Official PMDA document (PDF)
• PMDA list page: PMDA Early Consideration documents

Source: Pharmaceuticals and Medical Devices Agency (PMDA) website, PMDA Early Consideration documents. This page was created by editing and summarising the PMDA document.

Consult the official document; this summary does not replace it. PMDA provides the English version as reference information, and the Japanese original prevails if the two differ. PMDA describes its Early Consideration documents as reference information reflecting the Agency’s views at the time of publication; those views may change as scientific knowledge develops.

Related Clinical Biostats Resources

• Cmax, Tmax and Exposure Metrics in Clinical Pharmacology explains pharmacokinetic exposure measures, including the AUC and Cmax discussed in this document.
• Bioequivalence: Average Bioequivalence (2x2 Crossover) introduces average bioequivalence, relevant to the document’s consideration of formulation comparability.
• All Clinical Biostats tutorials provides access to the wider tutorial library.
• Statistical Calculators provides access to the available statistical calculators.