EPO Board of Appeal: T 0251/25 Empagliflozin Patent Revoked Over Post-Published Data

• The European Patent Office's Board of Appeal revoked a European patent for Empagliflozin (Jardiance) in decision T 0251/25.
• The Boehringer Ingelheim patent was found invalid despite the submission of post-published clinical data.
• Empagliflozin is approved in the US for reducing cardiovascular death risk in type 2 diabetes patients and in Europe for heart failure.
• The T 0251/25 decision indicates that post-published data does not always suffice to save a patent if the initial disclosure is inadequate.

The Board of Appeal's ruling suggests a stricter interpretation of the plausibility requirement, indicating that merely having post-published data available does not automatically guarantee a patent's survival if the initial disclosure is deemed insufficient.

The European Patent Office's Board of Appeal, in a significant ruling designated T 0251/25, recently decided to revoke a European patent held by pharmaceutical giant Boehringer Ingelheim. This patent pertained to the widely recognized drug Empagliflozin, marketed under the brand name Jardiance. The core of the dispute and subsequent revocation centered on the insufficiency of the patent's original disclosure, which post-published clinical data failed to adequately remedy.

Empagliflozin has approvals across different regions: in the United States, it is sanctioned for its efficacy in reducing the risk of cardiovascular death among adults diagnosed with type 2 diabetes who also have established cardiovascular disease, for reducing the risk of cardiovascular death and hospitalization for heart failure in adults with heart failure, and for treating chronic kidney disease. Similarly, within Europe, the drug's approval extends to the treatment of type 2 diabetes mellitus, symptomatic chronic heart failure, and chronic kidney disease. The Board's decision underscores a critical aspect of patent validity, particularly concerning the reliance on evidence generated after the initial patent filing.

Within the framework of European patent law, particularly as interpreted and applied by the European Patent Office (EPO), there is a well-established practice allowing for the submission of clinical data that becomes available after a patent application has been filed. This "post-published data" is often crucial for demonstrating a technical effect or an inventive step, especially in the complex field of pharmaceutical inventions where full clinical proof may not exist at the time of initial filing. However, the T 0251/25 decision serves as a potent reminder that this allowance is not without stringent conditions.

The Board of Appeal emphasized that such subsequent data cannot be used to introduce entirely new technical information or to establish plausibility for an effect that was not, at the very least, implicitly suggested or made credible by the original patent application. This ruling suggests a potentially stricter application of the "plausibility" standard, indicating that merely possessing compelling post-published data does not automatically guarantee the validity of a patent if the initial disclosure is found wanting. It reinforces the fundamental principle that the patent application itself must contain a sufficiently robust and comprehensive disclosure from the outset.

The implications of the T 0251/25 decision are far-reaching for pharmaceutical companies, including Boehringer Ingelheim, and for the broader landscape of patent prosecution within the European Union. This ruling signals a potential tightening of the EPO's stance on the acceptability and weight given to post-published clinical data, particularly when it comes to supporting the patentability of new therapeutic uses or formulations. For legal professionals advising pharmaceutical clients or prosecuting patents before the EPO, this decision highlights the imperative of ensuring that initial patent applications are exceptionally thorough and provide a strong, plausible basis for all claimed technical effects.

Over-reliance on the future generation of clinical data to "save" a patent application may now be viewed with greater skepticism. This could necessitate a strategic re-evaluation of filing practices, emphasizing the need for comprehensive experimental data or strong theoretical support at the earliest possible stage to withstand rigorous examination and potential opposition proceedings, thereby impacting Jardiance patent validity and similar pharmaceutical patents.

Lawyers advising pharmaceutical clients or prosecuting patents before the EPO should note this decision's implications for relying on post-published clinical data to support patentability, as it indicates a potential limitation or stricter scrutiny of such evidence.

Source: Original reporting via source material