The process of getting a new drug from the laboratory all the way to the pharmacy is lengthy and expensive.

And of course, many drugs do not even make it through this process – the FDA estimates that, while 70% of drugs successfully make it through phase 1 trials, only a third of these successfully pass through phase 2, and only 25-30% of these get through phase 3 and progress towards marketing approval.

In view of these stacked odds, exclusivity such as patent protection is vital for innovator pharma companies to recoup their R&D investment.

It is therefore little wonder that an effective patent protection strategy, over the whole lifecycle of a drug, is regarded as ‘mission critical’ in the pharma field.

Patently obvious?

A patent is a legal monopoly on an invention. For a limited term, it allows its owner to take legal action against anyone who tries to use the invention without permission, within a certain jurisdiction.

For innovative pharmaceutical companies, patents covering their approved drugs are a primary line of defence against generic competition. More broadly, a strong patent position in a particular technical area can serve as a ‘keep off the grass’ notice to competitors working in similar fields.

Patents are granted for products or processes which are new and inventive (i.e. not obvious) in view of the relevant ‘state of the art’.

In the pharmaceutical field, the discovery of novel compounds or biologics with interesting activity (e.g. inhibiting a particular disease target) offers the possibility to obtain what is arguably the most robust form of pharmaceutical patent protection, a patent for the drug product per se.

Such a patent provides a monopoly over manufacture, sale and use of the drug for any medical use, including potential future uses which might be identified during the lifetime of the patent.

However, innovation does not stop once a lead compound has been developed. The search to maximise the benefit to patients (and return on investment) is ongoing, whether identifying new indications, improving the balance between side effects and efficacy, improving convenience for the end user, or developing efficient and scalable methods of synthesis and production.

Patents can be obtained for diverse ‘follow-on’ pharmaceutical inventions, such as optimised methods of synthesis, special drug forms such as polymorphs and enantiomers, formulations, combination therapies, dosage regimes and new medical indications.

Obtaining patent protection

Obtaining a patent for a pharmaceutical invention typically involves specialist lawyers called patent attorneys, who work with the inventors to provide a detailed description of the research project leading to the invention, and a careful definition of the invention(s) for which patent protection is sought.

The patent application is examined by patent offices around the world: it can take several years (often involving detailed negotiation with the examiners, known as “prosecution”) before patents are actually granted.

Patents are territorial, so for products with global reach (which applies to most pharmaceuticals) a ‘family’ of patents is usually wanted, one in each jurisdiction where protection is needed.

Although an international patent application, covering over 150 countries (a so-called 'PCT' application), is available, this is essentially just an administrative shortcut: eventually the application is sent to patent offices in each jurisdiction of interest, incurring associated official fees and prosecution costs.

Centralised grant procedures do exist in some regions. For example the European Patent Office grants a single patent covering 39 European countries (including the whole of the EU, the UK, and others).

Once the patent is granted by the EPO, however, the patentee must decide whether to pursue and maintain the patent in each of those countries. This process is called validation.

Various factors are taken into consideration by pharmaceutical companies when deciding where to validate, including enforcement considerations, demographics, economics, and relative costs.

Since June 2023 it has also been possible to obtain from the EPO a Unitary Patent which is a single, indivisible, patent right covering 17 EU countries. The UP is an alternative to the ‘bundle’ of European patents obtained by the traditional validation route: this therefore adds a further decision for pharmaceutical companies to make regarding their patent portfolios.

Length of patent protection

The standard ‘term’ of a patent is 20 years from its filing date: this is now harmonised across nearly all countries. However, many countries worldwide offer the possibility of patent term extensions (PTEs) for patents covering pharmaceutical products (in Europe these extensions are known as Supplementary Protection Certificates).

These can extend the term by up to 5 years, with the possibility of a further 6-month extension in certain circumstances, the aim being to compensate a patent owner for some of the patent term that is effectively “lost”, by having to go through the lengthy regulatory trials and approval process.

For a particular drug product, there may be a number of patents to consider from a PTE perspective: selecting a patent for extension usually involves detailed strategy considerations.

Disputes involving patents

If a third party seeks to challenge the validity of a pharmaceutical patent, for example to “clear the way” for a generic launch, they may have a number of options.

In Europe, for example, following the centralised EPO grant procedure there is a central opposition procedure where an opponent can present arguments and evidence in the hope that the patent will be revoked or limited in scope, with effect across all 39 countries.

Revocation challenges in national courts are also possible. It is primarily also the national courts who decide on infringement disputes i.e. where a patentee seeks to prevent unauthorised use of their invention, or financial compensation for such use.

Since June 2023 a new Unified Patents Court has been open, which has the power to hear disputes relating to European patents and to make decisions with effect across 17 countries.

Patents, however, can be ‘opted out’ of the new system during an initial transitional phase – it is thought likely that most high value pharmaceutical patents will avoid its jurisdiction for now, although some of its earliest cases do involve biotechnological inventions.

Julie Carlisle is Partner, Patent Attorney, Litigator at IP firm Mewburn Ellis