A milestone decision on the patentability of second medical use claims

Managing IP is part of Legal Benchmarking Limited, 1-2 Paris Gardens, London, SE1 8ND

Copyright © Legal Benchmarking Limited and its affiliated companies 2026

Accessibility | Terms of Use | Privacy Policy | Modern Slavery Statement

Cookies Settings

A milestone decision on the patentability of second medical use claims

Sponsored by

gun+partners_40th-logo.jpg
pills-384846.jpg

Selin Sinem Erciyas and Aysel Korkmaz Yatkın of Gün + Partners explain the significance of a ruling in Turkey on the validity of second medical use patents granted by the European Patent Office

As per the European Patent Convention (EPC) definition, a substance or composition that is already known to have been used in a “first medical use” may still be patentable for any second or further use, provided that said use is novel and inventive.

Even though first medical use was the subject of patent protection within the EPC 1973, this convention did not regulate that the substance could be subject to a patent in different medical uses (second/further medical use). While there was no regulation in EPC 1973, claims regarding second and further medical uses of a known substance could be protected following case G5/83 of the EPO Enlarged Board of Appeal, provided that the claims are written in the ‘Swiss-type claim’ format.

As of the EPC 2000 amendments, a basis for second and further medical uses has been introduced in Articles 54 (4) and (5) of the EPC.

Although Turkey has been a signatory of the EPC since 2000, and the national law is mostly harmonised with the EPC provisions, Turkey refused to explicitly provide for the patentability of second or further medical claims in its national law. Instead, during the oral discussions at the parliament, government officers stated that any patent granted by the European Patent Office (EPO) will be protected in Turkey as per Turkey being a signatory of the EPC.

A decision that will shape future disputes

The validity of second medical use patents granted by the EPO before the EPC 2000 amendments is still frequently challenged by generic drug manufacturers. Finally, this issue was evaluated in detail by the General Assembly of the Court of Appeal (GACoA) on October 21 2021, and the court’s ruling should guide future disputes.

In the relevant case, one of the IP courts in Istanbul ruled that the patent disclosing a second medical use of a known substance must be revoked as the EPO granted it before the EPC 2000 amendments, when there was no explicit provision on the patentability of second/further medical use claims.

The court considered that Turkey is bound by the EPC provisions as a member of the European Patent Organisation, but not by the case law numbered G5/83 of the EPO Enlarged Board. In the absence of explicit provisions on the patentability of second/further medical use claims, the decision to grant such patents is groundless and therefore null and void.

The patentee appealed the decision before the Court of Appeal, which reversed the decision in the patentee’s favour. However, unexpectedly, the first-instance court resisted the reversal decision of the Court of Appeal, and therefore the case was referred to the GACoA.

The GACoA overturned the first-instance court’s resistance decision by finding it undue and unlawful. In its decision, the GACoA made important determinations, especially on the patentability of second/further medical use patents in Turkey.

The GACoA indicated that second medical use claims were protected by the EPO case law during the EPC 1973 period, before the entry into force of EPC 2000, which introduced Articles 54 (4) and (5). Furthermore, the GACoA rebutted the first-instance court’s claim that the court was not bound by the EPO case law.

The GACoA stated that, since Turkey had accepted the EPC 1973 and EPC 2000 provisions, the invalidity examination of European patents for first and second medical uses should be conducted by taking into account the EPC provisions and case law. In this respect, the GACoA stated that since the patent is a European patent, it should be examined to ascertain whether it meets the patentability criteria under EPC 1973, which was in force at the time of application of the patent.

According to the GACoA, a patent cannot be revoked just because it is a second medical use patent granted during the EPC 1973 period.

The GACoA considered that, although the first-instance court is a specialised IP court, it is not possible to resolve the dispute only with the legal knowledge of the judge and it should be resolved by taking the opinion of a technical expert.

Finally, the GACoA ruled that any patent, including second medical use claims, can only be revoked after conducting a true novelty and inventive step assessment. The GACoA rejected the arguments of the first-instance court that second medical use claims granted during the EPC 1973 period lack legal basis. Thus it has ended years of debate on this issue with a satisfying and solid decision.

more from across site and SHARED ros bottom lb

More from across our site

Gerben IP’s first woman partner, Sophie Edbrooke, explains how boutique life allowed her to broaden her expertise, take on leadership responsibilities and carve out a route to the top
INTA has a right to protect its Annual Meeting, but making it harder for others to hold similar events risks leaving delegates with a bigger travel bill
The firm says it hopes to capture patent litigation work in Texas by arming itself with experienced trial lawyers with venue expertise
Ken Iijima's arrival continues a trend of ex-Pizzeys practitioners joining RnB IP, whose co-founder says independent ownership and a lucrative compensation model have become attractive in a consolidating market
McDermott Will & Schulte lawyers explore why the UPC is seeing rapid adoption by medtech for fast-moving disputes, while pharma and biotech take a cautious, selective approach over revocation risks
IP firms may be growing more comfortable with external capital, but uncertainty over who could ultimately own the business is complicating the investment pitch
The former Western District of Texas judge addresses perceptions of his courtroom, reveals what comes next as he returns to practice at A&O Shearman and explains why marathon running is ‘cathartic’
International Anti-Counterfeiting Coalition says it has been blocked from hosting its annual event in the city, ending a long tradition of holding the gathering in the days leading up to INTA’s flagship event
The ITC is a powerful tool for litigators, practitioners say, as the threat of an exclusion order on a critical tech component could mean disrupting the entire data centre's operations
Anna Toh plans to expand Rajah & Tann’s soft IP capabilities, leveraging its Southeast Asia network to support clients on cross-border portfolio management and commercial strategy
Gift this article