Brazil's Patent Office Finalizes New Guidelines for Medical Use Inventions, Accepts Post-Filing Data but Maintains Restrictions on Dosage Regimens

Brazil's Patent and Trademark Office (BRPTO/INPI (搜索)搜索该词条) has published the final version of its revised examination guidelines for patent applications covering new uses of known products, concluding a public consultation process that began nearly a year ago. Ordinance #80/2026, enacted on June 30, 2026, amends Chapter 9 of the Chemistry Examination Guidelines originally established under Rule #208/2017, and introduces several important adjustments that will shape how pharmaceutical and biotechnology companies pursue patent protection for new medical uses in Brazil.

The final text reflects extensive stakeholder engagement, including input from Brazilian and international associations, and represents what many observers consider a more balanced approach compared to the initial draft published in July 2025 under Call for Contributions #02/2025.

Post-Filing Data: A Significant Reversal

The most consequential change in the final guidelines concerns the admissibility of post-filing data. The initial draft had firmly stated that post-filing data should not be accepted to address lack of enablement, treating such submissions as the addition of new matter under Article 32 of the Brazilian Patent Statute. Under that earlier proposal, only uses unequivocally and sufficiently proved in the specification as filed—preferably through in vivo tests—would be considered enabled.

This restriction drew widespread criticism from stakeholders, who argued that generating comprehensive in vivo data at the time of filing is highly impractical given that patent applications typically occur at early stages of technology development.

The BRPTO ultimately stepped back from this restrictive position. The final text explicitly foresees the acceptance of post-filing data, though with an important caveat: such evidence will only be considered admissible when the application as originally filed contains sufficient information to render the claimed use credible, rather than merely speculative.

For new medical uses specifically, in vitro, ex vivo, or in silico data can now serve as a basis to claim therapeutic activity. However, the BRPTO still refers to in vivo data as preferable for validating such effects. Critically, if the application includes only instructions, research plans, descriptions of incomplete studies, or trials, the medical use will not be considered enabled.

"If doubts remain during examination, complementary information may be submitted to confirm or corroborate what was already disclosed in the application as originally filed," the guidelines state, while making clear that "post-filed evidence cannot cure an insufficiency that existed at the filing date."

Markush Formulae and Antibodies

The final guidelines also address enablement requirements for compounds defined by Markush formulae and antibody-related inventions. For Markush formulae, therapeutic activity needs only to be demonstrated for at least one representative compound of each chemical class corresponding to the different substituents encompassed by the formula. This alignment with examination standards already applied to product claims should help avoid mismatches between compound claims and new-use claims.

Antibody inventions face stricter treatment. Enablement will be recognized only for antibodies expressly characterized by their complementarity-determining regions (CDRs) or variable regions and supported by experimental data in the working examples. For instance, where a claimed use refers broadly to an "anti-CD20 antibody," sufficiency will generally be limited to the specific antibody that was evaluated and defined by its CDRs or variable regions.

Dosage Regimens and Patient Groups: Restrictive Position Maintained

Despite requests from multiple stakeholders, the BRPTO kept unchanged its longstanding restrictive stance on therapeutic features in medical use claims. Features such as dosage, therapeutic regimen, route of administration, dosing interval, timing of administration, and patient subgroup selection are not considered essential technical features of a new medical use and cannot establish novelty over the prior art.

For example, a claim directed to the use of a known compound to prepare a medicament for treating a known disease will not be considered novel merely because the claim specifies oral administration twice daily, administration 30 days after diagnosis, or treatment of a subgroup of patients such as diabetics, children, or the elderly.

This position contrasts with developments in neighboring jurisdictions. Argentina, for instance, repealed guidelines in March 2026 that had systematically excluded entire classes of pharmaceutical patent claims and now permits dosage and administration regimen features, provided a non-obvious technical effect or unexpected therapeutic advantage is demonstrated.

The BRPTO's rationale is that features concerning how a medicament is administered relate to a therapeutic method rather than to the use of the compound in the manufacture of a medicament. Similarly, patient-group limitations are considered inconsistent with Swiss-type claims where the relevant disease or pathological condition is already known. Applications whose point of distinction over the prior art lies mainly in dosing schedules, routes of administration, or patient subgroups remain likely to face rejection at the administrative level, with these issues expected to continue being disputed before Brazilian courts.

Claim Format and Clarity Requirements

The accepted claim format for medical use inventions remains the Swiss-type format: "Use of product X for preparing a medicament for treating disease Y." Claims directed to direct therapeutic use, such as "use of product X in the treatment of disease Y," continue to be treated as therapeutic methods and therefore as subject matter not considered an invention under Article 10, VIII of the Brazilian Industrial Property Law.

The guidelines also impose clarity requirements: new medical use claims must clearly define both the product and the disease or pathological condition. Claims referring to generic disorders, syndromes, symptoms, or broad therapeutic areas are not accepted. Claims defining conditions by mechanism of action rather than by identifying the disease—such as "as a serotonin reuptake inhibitor"—are similarly rejected.

Inventive Step Assessment

The final guidelines spell out several non-exhaustive circumstances that may indicate absence of inventive step, including situations where the prior art discloses the same mechanism of action for the claimed disease, where the known mechanism involves a pharmacological target already known to be involved in the pathology, or where the new use can be inferred from known adverse effects of the product.

A notable nuance concerns biological pathways: for an inventive step objection based on blocking or activation of a particular pathway, the prior art should preferably show both the effect of the compound on that pathway and the contribution of the pathway to the treatment of the disease. This may provide applicants with room to argue that a mere reference to a target or pathway is insufficient unless the prior art also supports a reasonable expectation of therapeutic effect.

Practical Implications

The final guidelines preserve the BRPTO's restrictive approach to dosage-regimen and patient-subgroup claims while offering meaningful flexibility on enablement through the acceptance of post-filing data. Applicants should ensure that Brazilian specifications for new medical use inventions include, at filing, experimental data capable of supporting the claimed therapeutic effect. In vitro, ex vivo, and in silico data may be useful, but the specification should explain why those data support the claimed treatment effect and why the invention is not merely speculative. Where possible, validated animal models or other robust evidence should be included.

Debates surrounding the patentability of dosage regimens, patient groups, and other treatment-related features are likely to continue, particularly as Brazil's position diverges from international trends seen in jurisdictions such as the United States, Europe, and Argentina.