Predicate Device Equivalence in Japan: Benchmarking against Existing Approved Products

1. Key takeaways

The benchmark for an equivalence comparison in Japan must be a medical device that is an existing product already approved in Japan — not an FDA predicate device, and not an equivalent device cleared under CE marking. GRZAN treats the search for the benchmark and the construction of the equivalence argument as an independent deliverable. There is only one valid benchmark source: existing products approved in Japan. The argumentation must cover three elements: structural principle, intended use, and performance specifications, and it must withstand review against the statutory criteria that define when two devices may be treated as comparable.

• Only devices already approved in Japan can serve as the benchmark for equivalence; FDA predicates and CE equivalents have no standing as primary evidence.
• Article 42, Paragraph 2 defines, in reverse, the boundary of equivalence: devices clearly different in shape, principle, method of use, or performance fall outside the certification standards.
• Public information on Japanese existing products is limited to approval information, so the search requires a combination of methods.
• Equivalence arguments most often fail on the performance dimension, where published data are scarce.
• Benchmark conclusions should be confirmed through PMDA pre-submission consultation where any doubt exists.

2. Legal basis

The equivalence argument serves the review judgment on approval, and its boundaries are set by the classification and certification provisions of the PMD Act. The key sources are as follows.

• PMD Act Article 23-2-5, Paragraph 2: the judgment of quality, efficacy and safety in approval review — the equivalence argument serves this judgment.
• PMD Act Article 2, Paragraphs 5 through 7: classification is designated by the Minister of Health, Labour and Welfare by generic name, forming the classification basis for the benchmark search.
• PMD Act Article 42, Paragraph 2: certification standards — devices clearly different from existing medical devices in shape, principle, method of use, or performance are not subject to the certification standards.
• Notification from the Director-General of the Pharmaceutical and Food Safety Bureau, MHLW, Yakushoku hatsu 0806 No. 3, August 6, 2014: the organizational requirements for approval application documentation.
• Current statute: Act No. 145 of 1960.

3. Expert insights

Insight 1: Article 42, Paragraph 2 defines the boundary of equivalence in reverse.

The situation in which the certification standards do not apply is when a device is clearly different from an existing medical device in shape, principle, method of use, or performance. These four dimensions are in effect the core elements by which Japan judges equivalence. Companies can use the provision in reverse: as long as an argument can be made, dimension by dimension, that the device is not clearly different, the equivalence argument has a foundation. This reverses the usual drafting direction — instead of asserting similarity in general terms, the dossier walks through each of the four dimensions, states the comparison, and cites the evidence. A benchmark argument built this way is difficult to attack piecemeal, because each dimension is independently supported.

Insight 2: Public information on Japanese existing products is limited, so the search needs combined methods.

Unlike some markets that publish complete technical summaries, the public information available for Japanese existing approved products consists mainly of approval information. GRZAN’s usual practice is to combine the generic name list, the approval information search, and necessary public literature to form a traceable chain of benchmark evidence. The goal is not merely to name a benchmark device but to be able to show, for every claim made about that device, where the information came from. A benchmark whose characteristics cannot be traced to public sources will not survive review, no matter how plausible the comparison looks on paper. The traceability chain also protects against a subtle risk: benchmarks that have been withdrawn or superseded. Recording the approval status and the search date for every benchmark candidate keeps the evidence chain current throughout the review period.

Insight 3: Equivalence arguments usually fail on the performance dimension.

Structural principle and intended use are relatively easy to argue from public information, but performance specifications — such as accuracy, durability, and output characteristics — often lack citable public data. This dimension requires the company to compare its own test data quantitatively against the published specifications of the existing product. A qualitative statement that performance is comparable carries little weight; reviewers expect numbers on both sides of the comparison and a discussion of any gap. Where published specifications for the benchmark are incomplete, the gap itself should be documented and, if necessary, resolved through PMDA consultation rather than left as an unsupported assertion in the dossier — stating the limitation openly is safer than papering over it.

4. Practical recommendations

• Recognize only Japanese existing approved products as benchmarks. Use FDA predicate devices and CE equivalent devices as supplementary illustration only, never as the primary evidence of equivalence, and document why each candidate benchmark was accepted or rejected so the search is reproducible.
• Build a comparison table across the four dimensions. Shape, principle, method of use, and performance — give a conclusion and an evidence source for each item.
• Compare performance specifications quantitatively. Use the company’s own test data against the published specifications of the existing product; avoid qualitative statements.
• Confirm the benchmark conclusion at pre-submission consultation. Where doubt exists, obtain a written position through PMDA consultation to reduce the risk of post-submission additions.

5. Verification checklist

• □ Are all benchmark objects existing products already approved in Japan?
• □ Does the comparison table cover all four dimensions: shape, principle, method of use, and performance?
• □ Have performance specifications been compared quantitatively rather than described qualitatively?
• □ Has the benchmark conclusion been confirmed through PMDA pre-submission consultation where necessary?
• □ Has the use of an FDA predicate device as primary evidence been avoided?

Legal information verified as of October 29, 2026.

How GRZAN can help. GRZAN provides medical device and IVD registration, quality system, in-country representative and local testing support for the Japanese market. Our team prepares J-GCP/J-QMS compliant dossiers, coordinates conformity assessments, and supports post-market vigilance obligations. Business enquiries: info@grzanglobal.com