The New EU Transparency Rules for Clinical Trials: Navigating Regulatory Disclosure and Patentability at the EPO and UPC

Since June 2024, the European Union has implemented new transparency requirements for clinical trials, mandating significantly earlier and more detailed publication of trial information through the Clinical Trial Information System (CTIS). For pharmaceutical innovators, this creates a critical patent law tension: while regulatory law pushes for early disclosure, patent law continues to demand novelty and inventive step — a dilemma we at MDLEGAL describe as the “squeeze” on clinical trial inventions.

The Regulatory Framework: CTIS and the New EMA Guidance

Since 2023, clinical trials in the EU must comply with the 2014 Clinical Trials Regulation, with CTIS serving as the single EU portal and a publicly accessible database. The new EMA guidance, which entered into force in June 2024, introduces four key changes:

• The total number of documents to be published is reduced to certain key documents
• Individual deferral options have been eliminated in favor of generally applicable publication timelines
• Structured data fields are introduced, to be filled directly by sponsors and which cannot be redacted
• Sponsors may now upload two document versions — one for the authorities and a redacted version for publication

Importantly, full responsibility for proper redaction rests with the sponsor, as Member States are neither obliged to check submitted documents for redaction errors nor to compare both document versions.

The Patent Law Tension

Early disclosure occurs at a stage when results on the therapeutic effect are not yet available — meaning the inventor must disclose the experimental setup before having confirmation that the idea actually works as anticipated. While patent law allows for certain extrapolations and does not always require confirmatory phase three results, this same lower standard could mean that clinical trial disclosures lacking results may still destroy novelty or render claims obvious.

Current EPO Case Law on Novelty

Therapeutic application claims are drafted in the “product for use” format under Article 54(5) EPC, with the therapeutic effect treated as a functional technical feature, and the doctrine of inherency does not apply in Europe. The development of EPO case law shows a clear trend:

• T 158/96 still left room for novelty arguments
• T 1859/08 established a certainty standard that made novelty arguments based on a clinical trial protocol without results almost impossible
• T 136/24 recently confirmed that the skilled person must be able to conclude with the required certainty that therapeutic efficacy has been shown

Even under the new transparency rules with more detailed protocols, this high standard will likely remain unfulfilled in the absence of trial results.

Inventive Step: The More Critical Hurdle

Inventive step is where things become considerably more difficult for patentees. The landmark decision T 239/16 held that the mere fact of an active agent being tested in a clinical trial creates an expectation of success. More recent decisions have pushed back against this automatism:

• T 2963/19 acknowledged that certain diseases pose particular challenges with low success rates
• T 1437/21 confirmed that clinical trial approval does not by way of heuristic imply an expected positive outcome
• T 136/24 explicitly rejected the idea that ongoing clinical studies automatically establish a legal presumption of success

Yet with full protocols under the new EU transparency rules — including pre-clinical results, earlier clinical data, and a detailed scientific rationale — arguing against lack of inventive step may become increasingly difficult.

First Insights from the Unified Patent Court

The UPC Court of Appeal established its inventive step framework in the landmark decisions Amgen/Sanofi and Meril/Edwards, both handed down on 25 November 2025. The first UPC decision dealing with clinical trial disclosures came from the Local Division Munich on 12 December 2025 — interestingly involving the same patent as EPO case T 136/24.

While the EPO held the treatment to be inventive, the UPC found it obvious: the crucial point for the Munich court was that the phase three clinical trial was near completion, and the trial’s uneventful course led to an expectation of success in the skilled person’s view. Strikingly, the parallel EPO decision T 136/24 took the opposite stance, holding that the near completion of a study is per se neither a positive nor a negative pointer when assessing expectation of success. The Munich decision is currently under appeal.

Strategic Recommendations from MDLEGAL

Based on our advisory practice, we offer the following recommendations for pharmaceutical companies:

• File early: If sufficient data are available to credibly disclose the therapeutic effect, file the patent application before clinical trial information becomes public via CTIS
• Add features for later filings: If the application is filed after disclosure, include additional features such as specific biomarkers, particular patient subgroups, or successfully redacted dosing information
• Dual filing strategy: Filing both before and after publication of the clinical trial protocol can be valuable, but requires very careful alignment of timelines and overall argumentation strategy to avoid later collisions between the two cases
• Minimize regulatory disclosure: Consider already at drafting stage what is scientifically essential — for example, background and rationale need not be in the protocol itself but may be included in the non-published Investigator’s Brochure
• Implement a robust redaction process: Since sponsors bear full responsibility and inadvertent uploads in the wrong section will be published, a structured process is indispensable
• Cross-functional coordination: Scientists, regulatory experts, and patent attorneys must work together early on, since even the progress of a clinical trial may factor into the obviousness assessment

Practical Conclusion

The new EU transparency rules fundamentally change the patent strategy landscape for clinical trial inventions. The recent divergence between the EPO (T 136/24) and the UPC Munich on the same patent matter demonstrates that case law remains in flux and that companies need a careful, case-specific strategy. At MDLEGAL, we accompany pharmaceutical innovators along the entire interface between regulatory disclosure and patent protection — to ensure that the regulatory “squeeze” does not turn into a patent law dead end.