In June, the launch of a generic version of the diabetes treatment 'Trajenta' was met with ongoing patent disputes, presenting significant challenges. South Korean pharmaceutical companies, however, are currently gaining the upper hand, particularly in the initial patent trials.

Korean United Pharmaceuticals and Korea Biochem Pharm recently secured favorable rulings in the patent trial concerning the 'DPP IV Inhibitor Formulations' patent', which validates their claims. This patent, related to Boehringer Ingelheim's 'Trajenta' (linagliptin) and its combination with metformin, 'Trajenta Duo,' is set to expire on April 30, 2027.

The ongoing patent trials are divided into two categories: invalidation trials aimed at nullifying the patent and passive scope confirmation trials to avoid infringement. Daewon Pharmaceutical was the first to file an invalidation trial last July, while Korean United Pharmaceuticals and Korea Biochem Pharm initiated passive scope confirmation trials. Although Aprogen Pharma and Ilhwa received favorable rulings on June 17, the delayed decision was due to procedural aspects.

Despite the product’s launch, the ongoing disputes over Trajenta highlight continued efforts to challenge non-registered patents. Currently, 13 disputes related to non-registered patents for Trajenta (including Trajenta Duo) are ongoing. These disputes involve formulations, manufacturing methods, and usage, divided into various "evergreening" strategies. Companies are actively identifying and challenging these non-registered patents, leading to a series of legal battles.

One confirmed victory involves a formulation patent set to expire in April 2027, originally challenged by Shinil Pharmaceutical. Though Shinil eventually withdrew its case, it had already secured a favorable ruling. Additionally, Genuone Science achieved the first victory in the non-registered patent disputes concerning another formulation patent expiring in 2027.

While lawsuits involving two manufacturing method patents and three usage patents remain ongoing, recent victories mark a turning point. The number of successfully challenged patents now exceeds those still pending.

Pharmaceutical companies are persistently challenging patents even post-launch, driven by the potential to reduce future liabilities, such as damage claims, by invalidating or circumventing patents.

In late May, Boehringer Ingelheim issued a formal notice, asserting that generic developers were infringing on its patents and warning of injunctions and damage claims if generics were brought to market. Despite this, 19 companies received approval to market 127 generic products, with some eligible for launch as early as June 9.

Under the current patent linkage system, generic companies cannot be challenged merely for selling their products. However, the issue arises because some patents were not registered on the Green List, creating uncertainty about potential legal actions multinational companies might pursue if the generics show significant market performance.

As South Korean companies continue to navigate and overcome these patents, industry speculation suggests they could gain a strategic advantage in future litigation if more patents are invalidated or circumvented. With the number of overcome patents now exceeding those still in contention, interest is growing in how far these patent disputes will extend between domestic pharmaceutical companies and the original patent holders.