Next year marks an important anniversary in chemical history. In 1916, Gilbert Lewis published his seminal paper on chemical bonding, “The Atom and the Molecule,” from which were born Lewis dot structures. The year 2016 then, marks the 100th anniversary of Lewis’s concept of the covalent bond model and electron pairs. Only 100 years ago, chemists and physicists were still trying to understand the basic building blocks of molecules. Today, with advanced computing and machines like the large hadron collider, scientists are continually pushing the boundaries of human knowledge.
Patents are often thought to contain subject matter that is cutting edge. The United States Patent and Trademark Office, for example, recently granted a patent to Airbus for a plane that could fly between New York City and London in one hour. What happens, though, when the science is so cutting edge that patent laws and procedure aren’t yet equipped to handle these new inventions?
I recently attended a lecture that had me thinking through such a scenario. The lecture was on the use of pharmacophore models in drug design research, in which advanced computing is used to search for chemical structures and predict a chosen biological activity. For example, a chemist may employ computational chemistry to search for chemical structures that fit within the binding pocket of the angiotensin converting enzyme (ACE). While the use of computers in drug discovery has been known for some time, the accuracy with which these super computers can predict the activity of a particular compound will eventually have significant consequences in the chemical patent field.
Today, most chemical patents which are directed to compositions of matter follow the same paradigm: disclosure of the preparation or synthesis of a new compound or material, followed by tests on the compound that provide evidence that the compound or material possesses the intended properties. In a patent for a new pharmaceutical, the patent will likely contain a synthetic procedure for the preparation of the compound and an in vitro test, for example, which demonstrates that the drug inhibits a certain enzyme. Likewise, a patent for a new polymer will also contain a synthetic procedure, followed by a particular test that could indicate that the new polymer has the desired increased tensile strength. Trying to convince a patent examiner that the new compound or polymer has the stated utility without the specific experiments to support that utility is an uphill battle.
With the use of computational chemistry and pharmacophore modelling, the paradigm could begin to shift. However, there are a multitude of issues that will arise as this type of research and development becomes the subject of more and more patent applications. A pharmacophore, for example, as defined by the International Union of Pure and Applied Chemistry, is “an ensemble of steric and electronic features that is necessary to ensure the optimal supramolecular interactions with a specific biological target and to trigger (or to block) its biological response.” In other words, a pharmacophore is an abstract collection of a molecule’s features that provide a desired biological response. Yet most countries prohibit the patenting of abstract ideas. The Canadian Patent Act states that “no patent shall be granted for any mere scientific principle or abstract theorem.” Accordingly, trying to claim abstract notions of combined molecular interactions could be problematic from the perspective of whether it constitutes patentable subject matter.
The desired breadth of such patents will also become a contentious issue. For example, a pharmacophore model may determine that a hydrophobic region at a certain moiety is necessary for activity. The inventor may therefore try to claim “any hydrophobic moiety” on the molecule that binds to a specific location on the biological target. While this may be supported by the pharmacophore model, it brings ambiguity into the patent as to what is actually protected. If you asked 100 chemists what constitutes a hydrophobic moiety, I suspect you would receive many different answers. And patent offices and courts do not like ambiguity.
Mike Fenwick is a patent lawyer with Bereskin and Parr LLP in Toronto and holds a master’s degree in organic chemistry.