The German Federal Court of Justice (BGH) has recently overturned a lower court decision, confirming the validity of a patent for Fampridine-SR used to increase walking speed in Multiple Sclerosis (MS) patients.

This judgment (X ZR 165/23) provides crucial clarity on two pillars of patent law: Novelty of medical uses and the inventive step regarding dosage regimes.

Key Takeaways from the Ruling:

1. High Bar for Novelty: The BGH reaffirmed that a substance’s suitability for a specific treatment is only considered “disclosed” if the prior art clearly and directly proves the effect. Pure expectations, estimates, or “promising” outlooks in prior art (e.g., in stock exchange prospectuses or study abstracts) are not enough to destroy novelty.
2. The “Roadblock” Principle: Even if a path seems promising based on early data (like Phase 2a), an inventive step can exist if the skilled person would have encountered unforeseen obstacles along the way.
3. Post-Priority Evidence: In a significant move, the court allowed the consideration of later insights to determine if a path was truly “feasible” at the priority date. If a clinical trial (like MS-F202) fails to show statistical significance for its primary endpoint, this serves as a technical “roadblock” that makes the final solution non-obvious.

Practical Tips for IP Professionals & Pharma Strategists:

Document Clinical Failures: If your clinical trials hit a snag or fail to meet primary endpoints initially, don’t see it only as a setback. These “failures” can be powerful evidence of non-obviousness if you later find a specific, effective dosage or a way to identify “responders”.

Scrutinize “Expectations” in Prior Art: When defending against a nullity action, distinguish clearly between what a prior art document hoped would happen and what it actually proved. The BGH is strict: Expectations are not disclosures.

Post-Hoc Analysis is a Valid Tool: The court ruled that using post-hoc responder analysis to prove a technical effect is valid, even if the method itself is statistical/mathematical. As long as it relates to a technical fact (like the property of a drug), it supports the patentability.

This decision is a win for research-driven pharmaceutical companies, providing a more robust framework for protecting complex dosage regimes and specific therapeutic indications.