Sitting in recent project meetings listening to the clinical team discuss possible signals from an oncology clinical trial, I was struck by the disconnect between the real life complexity and uncertainty versus the view taken by the EPO (and other patent offices) that the existence of a clinical trial protocol can give the skilled person a reasonable expectation of success absent evidence to the contrary in the state of the art (at the EPO for example see T 2506/12, T 239/16 and more recent examples T2963/19, T 0096/20 and T 1123/16).
In order to obtain ethics approval to run a trial, pharmaceutical companies may have a rationale sufficient to pass ethics approval that the tested therapy may have sufficient efficacy and tolerable safety, but does this really rise to the bar of a reasonable expectation of success? It would be wrong to translate ethics approval into a patent test for obviousness.
This is particularly true in the field of oncology where patients may have no other option (having exhausted conventional treatments) – in these circumstances a mere hope may be enough to enrol in a trial. In particular, Wong et al looked in 2019 at clinical trial success rates by indication. Oncology had a 57.6% success rate moving from phase 1 to phase 2, only a 5.7% success rate moving from phase 2 to phase 3, a 35.5% success rate from phase 3 to approval, and an overall success rate of 3.4%. Obviously there are multiple factors determining whether a product moves to the next development phase and these figures may not truly reflect what is happening in practice (for example, it is increasingly common to move from phase 1 straight to phase 3, or for phase 2 to become registrational based on a conditional approval) but even factoring this in it cannot be the case that every trial is started with an expectation of success.
Of course there are steps companies can take to mitigate against these prior disclosure effects. Reviewing clinical trial protocols to remove material that may become prejudicial to a future patent filing, or filing based on pre-clinical material (if possible) are strategies to minimise these problems. And as different patent offices adopt different approaches, one should never base a filing strategy solely on the position adopted by one country. But it remains an issue, especially since there is increased focus on re-purposing existing therapies where the data needed to support the filing may only become available upon conclusion of the clinical trial. Talk to us about ways in which you can manage patent strategy versus clinical trials.
