Patent Status
Background information on about the patent status of essential medicines

A granted patent allows the patent holder to prevent others from commercially using the invention and, for example, to manufacture, sell, export or import the patented medicine. The question whether a specific medication is protected by a patent determines whether a generic formulation of the same medicine can be imported or locally procured. The electronic EML thus contains links to patent information to provide a first indication on whether a specific product is (still) protected by patents.

It is not possible to provide a straightforward answer to the question whether a medicine is patented or not for two main reasons:

1) Patents are territorial rights and thus are valid only for the country or region (i.e jurisdiction) where they are applied for and granted. The patent applicant may decide to apply for and pursue patent protection in one country but not in another. For example, the primary patents for sofosbuvir, a medication used for the treatment of hepatitis C, were not filed in Morocco and Georgia making it possible to locally produce or to import generic versions of sofosbuvir. Different patentability criteria and the practice of patent offices can vary from country to country, thus the same patent application may be granted in one country and rejected in another. For example the Egyptian patent office refused a specific patent application on sofosbuvir as it considered that the application did not fulfil the conditions for patentability.

2) One will often find numerous patents relating to one medicine. It is possible that a patent protecting a medicine expired, while others are still active. Thus, it is difficult to say that a medicine is “off patent”. Product patents that claim the chemical molecule/the active pharmaceutical ingredient are usually the strongest patents, as the patent holder can use product claims to prevent others from making, selling, or importing the chemical product. For this reason it is referred to as the “primary patent”. Patents on specific pharmaceutical formulations, method of use, product derivatives, and processes are considered “secondary patents”. Secondary patents are generally easier to circumvent (“to invent around”), meaning to make the medicine without infringing the secondary patents. For example, a patent on the aqueous solution would not prevent competitors to produce a tablet, and a patent on the fixed dose combination of two medicines would not prevent competitors to produce and market the two products separately.

The following are different types of patents:

Product patents claim the chemical molecule/the active pharmaceutical ingredient. Product patents are usually the strongest patents as the patent holder can use product claims to prevent others from making, selling, or importing the chemical product.

Product-by-process patents define the product by its process of preparation.

Process patents claim a (new) production process for an active pharmaceutical ingredient.

Formulation patents relate to the specific dosage form (e.g. coated tablet, soft gel capsule, syrup etc.).

Combination patents claim the combination of new or existing medicines.

Patents on product derivatives claim a specific form or derivative, e.g. a salt of an existing compound.

Patents containing Markush claims refer to a chemical structure with multiple alternatives in a format such as “chemical compound A wherein X1 is selected from a group consisting of a, b and c”.

This list is simplified and not exhaustive. Detailed explanations can be found in Philip Grubb, Peter Thomsen, Patents for Chemicals, Pharmaceuticals, and Biotechnology, 5th Edition Oxford 2010 as well as in the patenting guidelines of the respective national or regional patent offices.

Another example are medical use patents. For example specific patents on the use of imatinib in gastrointestinal stromal tumors were granted in Europe and South Africa, but not in India and Brazil. Countries where this patent was granted cannot yet procure generic imatinib for treatment of gastrointestinal stromal tumors, but can do so for other indications (i.e. chronic myeloid leukemia) if the primary patents have expired. The patent references included in the EML focuse on the most relevant patents that potentially limit generic competition.

Three different indications are used throughout the list:

  • Patents have expired in most jurisdictions
This means that primary and relevant secondary patents have expired (if filed at all). New secondary patents covering processes, formulations or second medical indications etc. could always be filed in certain jurisdictions, but in general the medicine is subject to generic competition.

  • Main patent is active in several jurisdictions. For more information on specific patents and license status for developing countries visit www.MedsPaL.org
The primary patent has not yet expired. Detailed information is available in www.MedsPaL.org.

  • Primary patents have expired, but secondary patents remain active in some jurisdictions. For more information on specific patents and license status for developing countries visit www.MedsPaL.org
Primary patents have expired, but secondary patents that are relevant for generic competition, e.g. fixed-dose combinations have not yet expired. Detailed information is available in www.MedsPaL.org.