What Makes A Good Patent?

Patents are filed for various strategic reasons and sometimes observers have difficulty discerning patent quality. What makes a good patent? There is no universal answer or formula. Reasonable people can look at the same patent and disagree on whether the patent is good or not. However, in the case of therapeutic patents, experimental data is vital to patent quality.

Unlike other types of patents, patents on therapeutics should have some experimental data in order to withstand challenges. In one case, Dr. Bonnie Davis invented a treatment for Alzheimer’s disease solely while reviewing the literature. The literature described that galanthamine had anticholinesterase properties. The literature also described an increase in short-term memory in dogs after administering galanthamine and a correlation between Alzheimer’s disease symptoms and a reduced level of acetylcholine in the brain. Dr. Davis deduced that galanthamine can be used to treat Alzheimer’s patients, and she was correct. She filed for a patent using prophetic examples, and the patent was granted on May 5, 1987. The experimental proof of her theory was completed two months later in July of 1987. In 1995, Dr. Davis licensed the invention to Janssen. Generic pharmaceutical companies seeking to market generic versions of Janssen’s drug successfully challenged the validity of this patent. The Federal Circuit affirmed the invalidity determination by the district court because relevant animal testing experiments were “not finished…by the time the ‘318 patent was allowed”. Judge Dyk wrote that “[t]ypically, patent applications claiming new methods of treatment are supported by test results,” and “under appropriate circumstances, . . . the first link in the screening chain, in vitro testing, may establish a practical utility for the [pharmaceutical] compound in question.” This case highlights the crucial importance of data to the validity of therapeutic patents. In re ‘318 Patent Infringement Litigation (Fed. Cir. 2009).  

The next consideration is how much data should be included in the patent application. Generally, broader coverage requires more data. In any case, more data is better, but this creates a dilemma. On one hand, the U.S. has a “first inventor to file system” – the first to file gets the patent. Wait too long to accumulate data and somebody else may get the patent first. File before you have sufficient data and the application may get rejected, or a weak patent may get issued that cannot withstand subsequent challenges. The latter comes with the wasted costs of the developing a therapeutic product only to see the benefits go to generics. A fact finder may find that there was insufficient proof that the invention would work for the intended purpose. For Star Trek fans, a patent application may describe a tricorder, but without more – it is still only science fiction. Even when credible, the details must be thorough enough to allow others to copy the invention after the patent expires. Finally, when very little data appears sufficient, a fact finder may view the invention as obvious. The decision on the quantity and quality of data needed is a balancing act usually decided with the help of counsel who is up-to-date on industry standards.

A patent applicant is required to submit enough data to show the inventor is in possession of the invention, the invention will work for the intended purpose, and that others will be able to practice the invention without undue experimentation. The level of data required in the patent application depends on the nature of the invention, but all therapeutic patents should have some data. A patent attorney helps to determine the sufficiency of the data by reviewing court cases where similar patents were upheld or invalidated. In many cases, it is still an educated guess. However, based on the current interpretation of the law, it is prudent to err on the side of having more data, especially in the case of therapeutic patents.