Pharma companies uncertain on data needed for plausibility claims

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Pharma companies uncertain on data needed for plausibility claims

Drug company lawyers say it is tricky determining the right kind and amount of data to support a claim because courts and examiners have different expectations of sufficiency to determine plausibility

In the fall out from the UK Supreme Court’s Warner Lambert v Generics decision, a higher and yet ambiguous bar for plausibility has left pharmaceutical innovators wondering how much data is needed to support their claims.


Senior sources at European pharmaceutical companies say that determining the right amount of data to include in a patent application constitutes a ‘Goldilocks conundrum’ where it is difficult to pick the correct option. Include too much data and the claim isn’t supported; include too little and the scope of the patent is too narrow.

This situation presents a problem for pharma companies that want to file a patent for as many diseases as the product could feasibly cover. 

“The rule of thumb when preparing patent applications is to resist the temptation to go as broad as possible,” says the IP director of a UK pharma innovator. “The trap people fall into is not taking the time to justify a wide breadth of data,”

He advises counsel to consider the breadth of the claim very carefully and the rationale behind the subsets of diseases the patent is trying to cover.

Finding the sweet spot of data also heavily depends on the type of data used, according to the head of IP at a European pharmaceutical firm. He says that finding the right type of data is one of his main concerns.

“On one level, you get a fairly good gut feeling when you have enough data,” he says. “The main issue is when you have computer data and then some sort of biological data that derives from a type of genetic testing.

“Once you’ve got good experimental data, you tend to be OK. The problem is really having no data at all.”

The head of IP at a Swiss innovator pharmaceutical company echoes his opinion, stressing that supplying something is better than supplying nothing.

“To go into a patent application totally naked without any data and just a bold assertion is risky. What you need to do is get some pre-clinical data to overcome the question of why filing without data would be even worse for your chances of approval,” he says.

“You can show that advantage by test tube data, or by animal tests. What you don’t always need is human data.”

Further complicating the question of how much and what type of data should be included to prove plausibility, all five industry sources say that the information can always vary depending upon the patent and the indication it claims to cover.

“What confounds this question of plausibility is that it is mostly determined on a case-by-case basis,” says the IP director of the UK pharma innovator company. “In some cases, even if you never put the drug into an animal it is still well established that just supplying in-vitro data is enough to prove it will work in a human. Sometimes it won’t.”



No one size fits all

Further complicating matter no general guidelines have been established that clearly explain what amount and type of data needs to be included in each claim because every claim is unique.

“There have been a number of cases to try to set a clear bar on how much is enough and establish the standard for plausibility,” says the IP director for a UK pharma innovator.

“But the decision making bodies, whether it’s the Court of Appeal or the EPO, have always come back saying plausibility is very case specific.

“It’s frustrating, but I understand why they are saying it.”

He adds that he cannot imagine one single ruling that could clear up all questions of how to prove plausibility because no two cases are the same: “There is no answer to having a perfect ruling. Everything depends on the type of disease and how trials are run.”

While plausibility is an innovator concern, they say they are not too concerned about generic companies using the matter to invalidate patents.

If anything, argues the head of IP at the Swiss innovator, plausibility will only be used to further nuance questions of sufficiency and inventive step.

“I don’t think we are particularly worried about this specific uncertainty because generic companies are going to try to invalidate our patents anyway, whether they are going to call it uncertainty or inventive step,” he says.

The cases most open to attack are those filed 10 or 15 years ago before plausibility even became a buzzword in the industry. The director of IP for another European pharmaceutical company compares litigating plausibility cases to playing the lottery.

“We are worried more about the invalidation of our older patents. You file today and you litigate 10 years from now.

“You don’t know what is going to happen but this is just the nature of the game,” he adds.

His concerns are shared by the head of patents for a drug company who says that the cases that will be litigated on the grounds of plausibility will mostly be determined on how the law evolves.

“It is an open question how these cases will be litigated in the future. You always end up litigating cases that were granted 10 to 15 years ago that would not necessarily be granted now. Where all this goes is yet to be determined,” he says.

With the Warner Lambert decision having been handed down late last year, pharmaceutical companies are still waiting to see how the question of plausibility evolves into the future.

The Swiss head of IP tells Patent Strategy: “Filing now is sometimes a game of semantics because for a long time plausibility wasn’t even a word in the vocabulary of patent offices. But these days you can’t move without it being thrown at you.”

Unfortunately given the level of uncertainty around what makes a claim plausible, pharma companies will be facing more than just semantic headaches when filing their patents.

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