Divergent Approaches to Second Medical Use Patent Protection Across Southeast Asia

The protection of second medical use claims in Southeast Asia varies significantly among ASEAN countries, reflecting differing legislative frameworks and patent office practices. This divergence impacts pharmaceutical patent strategies and innovation incentives across the region.

Thailand has taken a progressive stance by enacting explicit guidelines that confirm acceptance of second medical use claims. The Thai Patent Act excludes methods of medical treatment from patentability but does not specifically bar new uses of known substances. The Department of Intellectual Property (DIP) issued examination guidelines in 2019 clarifying that new medical uses can be patented provided they do not constitute a method of treatment and satisfy novelty, inventive step, and industrial applicability requirements. Acceptable claim formats include Swiss-type claims, although claims must avoid referencing dosage or therapeutic steps that imply treatment efficacy.

Indonesia presents a pragmatic approach to second medical use patenting. While Article 7(b) of the Indonesian Patent Law excludes methods of medical treatment from patent protection, the country has adopted principles akin to the European Patent Convention (EPC) to allow “product for use” type claims. This approach effectively circumvents the legislative bar by permitting patent claims framed as “Substance X used as a medicament for Disease Y.” Although the 2016 Patent Law is under review and the Directorate General of Intellectual Property is considering removing the exclusion on medical treatment methods, current patent office practice remains somewhat inconsistent. Nonetheless, patent grants for new indications continue to be observed.

At the other end of the spectrum, Cambodia and Myanmar exclude pharmaceutical patent protection entirely. Consequently, discussions on second medical use claims are unnecessary within these jurisdictions, as no patent protection for pharmaceuticals is available.

The Philippines maintains a restrictive legal environment for second medical use claims. Section 22.1 of the Philippine Intellectual Property Code, introduced in 2007 through the Cheaper Medicines Act, excludes from patentability the mere discovery of new uses or properties of known substances unless such discoveries enhance the known efficacy. Although the Intellectual Property Office of the Philippines (IPOPHL) revised its Guidelines on the Examination of Pharmaceutical Applications Involving Known Substances (QUAMA Guide) in 2018 to address “new use” claims and introduced an “inherency” criterion, the general consensus among practitioners is that second medical use patent protection remains effectively closed. The guidelines suggest that a new use is patentable only if it is not inherent in prior art, but this threshold is difficult to meet. Moreover, as the guidelines are non-legislative, they are unlikely to override the statutory exclusion aimed at ensuring medicine affordability.

A common principle across these jurisdictions is the exclusion of methods of medical treatment from patent protection. However, this exclusion does not uniformly preclude patenting new medical indications for known substances. The legal nuances and patent office practices differ, influencing the scope and enforceability of second medical use patents.

For example, in Indonesia, despite Article 4(f) of the Patent Law seemingly conflicting with the allowance of Swiss-type claims, the patent office continues to grant patents with claims framed as “Substance X used as a medicament for Disease Y.” This reflects a transitional phase pending legislative reform.

Thailand’s approach balances the exclusion of treatment methods with recognition of new medical uses, provided claims avoid therapeutic steps. The DIP’s 2019 guidelines serve as a practical framework for patent examiners and applicants.

In contrast, the Philippines’ statutory exclusion under Section 22.1 IP Code remains a significant barrier. The 2018 QUAMA Guide’s introduction of the inherency test offers some interpretative flexibility but does not fundamentally alter the patentability landscape.

Cambodia and Myanmar’s outright exclusion of pharmaceutical patents places them outside the scope of second medical use patent discussions.

In summary, the landscape for second medical use patent protection in Southeast Asia is heterogeneous. Thailand and Indonesia demonstrate evolving, pragmatic frameworks that recognize the value of protecting new medical indications. Meanwhile, Cambodia, Myanmar, and the Philippines maintain restrictive or exclusionary policies reflecting broader public health and access considerations. Patent applicants and practitioners must navigate these jurisdiction-specific nuances carefully when formulating patent strategies in the ASEAN region.