The confidentiality of patient data is an essential consideration in any clinical trial — but stakeholders must also consider the confidentiality of the invention being trialled. If just one member of the public can access information about the invention before a European patent application is filed — whether this is through writing, oral disclosure or use — the invention may lack novelty.

This is so important due to the sheer number of stakeholders involved in a clinical trial, which can include sponsors, Contract Research Organisations (CROs), investigators and site personnel, healthcare personnel, regulatory agencies and participants.

We’ve recently given five top tips to help you ensure that confidential information remains completely confidential. Here, I explore some more tips to ensure that the performance of a clinical trial doesn’t become novelty-destroying prior art.

1. Ensure that you have confidentiality agreements in place which include IP provisions

Clinical trials themselves don’t guarantee confidentiality, as illustrated by the UK Courts in AGA Medical Corporation V Occlutech (UK) Limited [2014] EWHC 2506. Here, Dr Kurt Amplatz provided a device for occluding defects in the arterial septum of the heart (e.g. a “hole in the heart”) to medical personnel at Bratislava’s Children’s University Hospital before the priority date of EP(UK)0957773.

The personnel involved in the first clinical trials of the occluder device weren’t under an express obligation of confidence as they weren’t asked to sign any form of confidentiality or non-disclosure undertakings. Mr Justice Roth found that the medical personnel weren’t under a duty of confidence in equity (implied confidence), concluding that there can be no presumption of confidentiality simply because this was a clinical trial of new medical devices.

As this case highlights, it can’t be assumed under UK Patent Law that a clinical trial on its own implies a duty of confidentiality. Accordingly, confidentiality or non-disclosure agreements play a key part in safeguarding a Sponsor’s proprietary information.

In contrast, during parallel Opposition proceedings at the European Patent Office (EPO), public prior use wasn’t considered to have been proven. This was based on established case law (T906/01, T152/03, T229/06) that in the medical field there is a prima facie assumption that any person involved in clinical tests of a prototype device is obliged to confidentiality.

2. Ensure a tight control over the fate of all non-used therapeutics at the end of the clinical trial

While the Boards of Appeal of the EPO found in T598/12 that a trial participant isn’t a member of the public in the strict sense, a particularly contentious area of law is whether unused and unreturned trial drugs form a public disclosure.

A general principle of the European Patent Convention, following the Enlarged Board of Appeal’s Decision in G1/92, is that the chemical composition of a product is state of the art when the product as such is available to the public and can be analysed and reproduced by the skilled person, irrespective of whether or not particular reasons can be identified for analysing the product.

Even a theoretic possibility of analysis is sufficient and this can have serious repercussions for clinical trials in which the therapeutic isn’t administered or implanted in a healthcare setting, as highlighted by the Boards of Appeal of the EPO in T7/07. Bayer Pharma AG’s patent European Patent No. 1214076 for the combined use of ethinylestradiol and micronised drospirenone as an oral contraceptive marketed as Yasmin® was revoked by the Opposition Division. One ground of attack during opposition was a lack of novelty due to public prior use. This was based on the fact that not all unused contraceptive tablets were returned at the end of the trial.

The women participating in a clinical trial of Yasmin® in the late 1990s hadn’t signed any confidentiality agreements. The Boards of Appeal concluded that after handing out the tablets Bayer had effectively lost control of them and the women were in no way barred from disposing of them as they wanted. As there was no explicit or indeed implied duty of confidentiality, the unused drug became publicly available. Although the women had been informed of the active ingredients, they were unaware that drospirenone was present in a micronised form. However, it was concluded that a theoretical possibility of analysis by a skilled person existed.

An incident like this might be prevented by including instructions such as “patient must return all unused drugs” in documentation relating to the accountability of dispensed drugs.

In the pending Opposition Appeal T41/17 (to be heard in mid-February 2020), Bayer is again defending the purported public prior use of unused tablets dispensed during clinical trials.

This time, the case relates to the control of non-administered tablets containing polymorph 1 of sorafenib tosylate, a cancer drug.

The Opposition Division followed T7/07 in agreeing that information given to patients cannot be regarded as prima facie confidential. Indeed, it might be considered unethical to bind trial patients by general explicit or implicit confidentiality obligations, as they should be able to discuss medication with their spouses and doctors. However, it was found that trial participants were under a legal obligation to use the tablets according to a stipulated schedule and return any non-administered drugs. In contrast to T7/07, loss of control over the return of the dispensed drugs hadn’t been established, as patients were legally prevented from disposing of the drugs and also from passing on information contained in them to third persons not bound by confidentiality. Any ‘breach’ therefore didn’t allow a conclusion to be made that the tablets were available to a member of the public.

Another Opposition Appeal to keep an eye out for in 2020 is T1427/16, the Oral Proceedings for which are scheduled for late June. The Opponent/Appellant Hexal AG asserts that the trial participants weren’t bound by a confidentially agreement and that the statement on the blister packs of alogliptin (“For clinical trial use only”) can’t be taken as a substitute of a confidentiality agreement. All tablets handed out to the trial participants became publicly available.

Hexal AG also asserts that even if a confidentiality agreement existed, Takeda lost control over the unused tablets handed out to participants who did not complete the study, particularly those participants referred to as “lost to follow-up”.

The Decisions from T41/17 and T1427/16 will provide further insight on what restrictions the EPO requires clinical trial participants to be bound by in order that unused drugs don’t become ‘public’.

3. Consider what information is required to be shared with the trial participant

You should refrain from disclosing any specifics of the drug being trialled to a trial participant that they are not required to be informed about. Then, even if the trial participant is found not to have a duty of confidentiality, the patentable features of the drug (such as polymorph and formulation) will arguably not have been made available to the public.

4. Consider filing a patent application prior to the announcement or performance of the clinical trial

Plausibility is currently a hot topic at the EPO, as patent applications attempt to meet the standards of sufficiency and inventive step. The EPO has repeatedly emphasised that it isn’t always necessary to report the results of applying the claimed composition in clinical trials (or at least to animals). However, the technical effect of the invention must be either self-evident, predictable or based on a conclusive theoretical concept (i.e. it must be plausible) at the time of filing, based on the information in the application and the common general knowledge of the skilled person. The inclusion of in vitro studies demonstrating the activity of the compound against a molecular target implicated in a disease may be considered sufficient to render the claimed effect plausible.

The timing is paramount — always liaise with your patent attorney to discuss the optimal time to file.