Biogaran v. Lundbeck and the Challenger’s Burden in Second Medical Use Cases
A second medical use patent is often seen as an easy target. The Milan section of the UPC Central Division has just shown that it is much harder to hit when the challenger is required to say exactly where the patent fails. On 9 October 2026, in Biogaran v. Lundbeck, the Court dismissed Biogaran’s revocation action against Lundbeck’s EP 4 223 296 and maintained the patent in amended form.
Three rules beyond nalmefene
The patent claims nalmefene, a molecule already known for the treatment of alcohol dependence, for reducing alcohol consumption in a specific group of patients. In Biogaran v. Lundbeck, the Court maintained it in the amended form that Lundbeck had already filed with the EPO Opposition Division. Biogaran was ordered to bear the costs and to pay an interim award of EUR 100,000 within three weeks.
The decision lays down three rules, each summarised in a headnote, and their reach goes well beyond nalmefene. First, the Court will not finish an objection of added matter that the claimant has left vague. Second, a claim limited to a group of patients does not need to state the dose, provided the skilled person can find a safe and effective one without undue effort. Third, when an obviousness case can only be built by combining more than ten documents, none of which points to the others, the case reflects hindsight, which the Court calls an ex post facto analysis.
For holders of second medical use patents, the message is encouraging, with some reservations. At every stage of the validity analysis, the Court asked the challenger to show precisely where the patent went wrong, and refused to do that work in the challenger’s place. The result is all the more notable because, three years earlier, an EPO Board of Appeal had revoked an earlier patent of the same family, covering the same group of patients, for lack of inventive step.
A patent with a difficult family history
EP 4 223 296 is a divisional patent, one of several descended from international application WO 2014/001427, filed on 27 June 2013. As construed by the Court, claim 1 covers nalmefene, taken as needed, to reduce alcohol consumption in alcohol-dependent patients who drink at a high-risk level (more than 60 g of pure alcohol a day for men, more than 40 g for women) and who are still drinking at that level one to two weeks after their first assessment. This observation period is the heart of the claim. It filters out the early reducers, patients who drink less as soon as they enter a treatment setting. According to the patent’s own figures, they made up more than half of the population studied.
Biogaran brought its action on 14 November 2025 and raised the four classic grounds: added matter, insufficient disclosure, lack of novelty and lack of inventive step. In parallel, Lundbeck had asked the Paris Local Division for provisional measures based on this patent and on EP 3 345 604, but that application was withdrawn by agreement between the parties. At the oral hearing on 15 September 2026, Lundbeck turned its conditional application to amend into an unconditional one and deleted dependent claims 7 and 9. The text defended before the UPC thus became identical to the one filed with the Opposition Division after its preliminary opinion.
Added matter: the challenger draws the map
Biogaran’s main added-matter argument was structural. The original application lists 135 numbered embodiments, which can be combined in millions of ways. In Biogaran’s view, the granted claim was therefore an arbitrary pick from that menu. Before looking at the substance, the Court set a rule of pleading. A party alleging added matter must compare the claim with the original disclosure, point by point, and identify exactly what has been extended. A long list of embodiments may raise questions of clarity or drafting style, but it does not in itself prove an extension. As an impartial body, the Court cannot build up an objection that the claimant has only stated in general terms, since doing so would amount to examining a ground of invalidity of its own motion.
In practice, the Court was less strict than its headnote. Because the required level of detail remains uncertain and the Court of Appeal has not yet ruled on it, the Court still compared the parent application with the patent, openly admitting that this amounted, to a limited extent, to an ex officio assessment. It found a direct basis for claim 1 in embodiments E24 to E26, read together, and checked that they had been carried over unchanged into each application of the divisional chain.
The principle was therefore announced, not yet applied as a sanction. Its real weight lies in future cases. After Milan, a challenger arguing that a parent application full of options cannot support any particular combination needs a map showing which feature is at stake, which passage it comes from, in which application of the chain the problem arises, and why the skilled person could not have derived the combination directly and unambiguously. A challenger who leaves the Court to draw that map should not expect it to do so a second time.
The dose the claim does not need
On sufficiency of disclosure, Biogaran’s strongest point concerned the dose. Claim 1 mentions none, while the clinical trials described in the patent used only 18 mg. The Court rejected the idea that a second medical use claim must, as a general rule, state the exact dosage in its independent claim. Following G 2/21, which it found persuasive without treating it as binding, the therapeutic effect is part of what is claimed and must be assessed under Article 83 EPC. Following T 0728/21, evidence published after the filing date cannot make credible an effect that was not credible at that date.
The decisive step came next. Using nalmefene for alcohol dependence was already known. The contribution Lundbeck relied on was a stronger reduction in drinking within a narrowly defined group of patients. Once the invention lies in choosing the patients, the dose becomes a question of implementation. The description disclosed a range of 10 to 20 mg and an effective regimen of 18 mg, the closest prior art (a 2007 study by Karhuvaara and colleagues) already reported efficacy at 10 mg, and every skilled person knows that very low doses may not work and very high doses may be toxic. It was for Biogaran to prove that the invention would fail at doses other than 18 mg, and it had not done so.
This is the passage most favourable to patentees, but also the one that depends most on the facts. A dosage regimen claim, where the dose itself is the invention, would call for a different analysis. For drafters, the lesson is simple: put the dose ranges and an effective reference regimen in the description, and keep the claim at the level of the patient group. For challengers, an insufficiency attack based on the dose needs technical evidence that the effect is absent in part of the range.
Thirteen documents and no pointer
The inventive step attack started either from Karhuvaara or from a 2011 Lundbeck press release, each combined with up to twelve other documents, ranging from the EMA guideline on medicinal products for alcohol dependence to cardiology trials and a cocaine-dependence study. The Court applied the test set by the Court of Appeal in Amgen v. Sanofi: the prior art must give a technically credible basis for reasonably predicting success, which the Court distinguished from a mere hope of success. It also referred to its own ruling of 4 May 2026. Relying on Kodak v. Fujifilm, the Court held that finding the necessary elements scattered across different documents and contexts is not enough without a pointer, and, following Fujifilm v. Kodak, that the reason to combine cannot come solely from the secondary document chosen with hindsight.
Only then did the Court address the mosaic. When an obviousness case can only be built by combining more than ten documents dealing with different technical questions, none of which provides the missing pointer, the mosaic itself shows that the analysis is ex post facto. The number of documents is only a symptom. An attack based on two documents that lacks a pointer fails for the same reason, simply less visibly.
Two Board decisions, one family
The strongest objection to an optimistic reading comes from the EPO itself. In T 0963/20, Board 3.3.07 revoked EP 3 138 564, an earlier patent of the same family, holding that the 2010 EMA guideline, which recommended stratifying patients by level of dependence, made the claimed group obvious. Milan looked at the same combination and reached the opposite result. In its reading, the guideline recommends stratification as a matter of trial methodology, does not use the drinking risk level as a selection criterion and does not suggest that nalmefene works better in the claimed group. The Court also refused to treat the Board’s decision as res judicata: an EPO decision may persuade the UPC, but it cannot bind it.
The EPO’s own position has since moved. On 24 July 2026, in T 0894/25, the same Board dismissed the appeals against the rejection of the oppositions to EP 3 345 604, the direct parent of the patent at issue, relying on a statistical analysis it did not have in the earlier case. The better explanation for the divergence lies in the test applied. Milan’s narrower question helps patentees whose contribution is a specific selection rule backed by data showing a different effect in the selected group. It gives no advantage to patentees in general.
Questions left open
This is a first-instance decision, and an appeal may be lodged within two months of its service. The opposition against EP 4 223 296 is also still pending: the Opposition Division heard the parties on 25 August 2026, no written decision had been entered in the European Patent Register as at 18 October 2026, and any decision can be appealed. If the patent were revoked there, the revocation would apply in all designated states, whatever the outcome in Milan. Infringement was not decided.
Lessons for both sides
For holders of claims limited to a group of patients, the decision rewards choices made long before any litigation: selection criteria with real clinical meaning, data showing that the effect differs in the claimed group, and a description that discloses the dose range and an effective regimen. It also shows the value of defending the same text before the UPC and in the opposition. For generic companies, each ground now comes with its own burden. An added-matter attack must follow each feature through the divisional chain. An insufficiency attack on the dose must be backed by evidence. An obviousness attack must identify the document that provides the pointer and the basis for expecting success. A generic company facing a patient-group patent should first find the one document that carries the pointer, and only then decide whether to fight in Milan or before the Opposition Division.
Dhenne Avocats acts for patentees and generic companies in these disputes, which we follow in our Pharma Litigation Watch. Contact the firm.
This article is an adaptation of an analysis by Matthieu Dhenne originally published on Kluwer Patent Blog on 20 October 2026: Biogaran v. Lundbeck and the Challenger’s Burden in Second Medical Use Cases.