A generic is a medicine containing a chemical compound that is an active pharmaceutical ingredient, identical to the one which was earlier invented and patented by the original developer of that medicine. Generics are allowed to enter a market only after a patent of the branded medicine expires and the production monopoly of the patentee company is no longer valid. Generic medicines can be sold under the international nonproprietary name or under some commercial name that is different from the brand name used by the original drug developer.
Generic manufacturing practice
The patent protection duration of a newly-invented drug depends on the patent legislation of each particular country. For instance, in the USA the effect of a patent extends up to 12 years. When the lifetime of the patent or other exclusive licenses expires, legislative limitations on the sale of the drug become void. From this very moment, almost any pharmaceutical manufacturer that has the opportunity to master the technology for the production of that medicine gets a right for fabricating a generic alternative of a formerly patented drug (provided the generic is produced by the same technology used in the genuine drug).
How do generics hit a market?
Unlike original drug developers, generic manufacturers do not have to conduct a complete cycle of clinical trials to bring their medicine to the market. For generic producers, it is pretty enough to have confirmation of Good Pharmaceutical Manufacturing Practice (GMP) and, sometimes, to conduct tests proving the bioequivalence of a generic drug to the genuine preparation in terms of absorption rates, mean time to reach maximum plasma concentration, drug distribution across tissues and body fluids as well as the type and rate of the drug clearance.
The need for running clinical trials is determined by the dosage form of the generic drug. For instance, in cases when the generics dosage form is presented by a solution of an active agent in a concentration close to the genuine drug (such as solutions for injections, drops and solutions for ophthalmic and nasal applications, liquors, solutions for inhalations, and powders for solutions), there is no need to carry out clinical investigations since the pharmacodynamic properties of solutions remain the same in both generic and original drugs.
Clinical studies are required for those dosage forms where the entry dynamics of the active ingredient into the body is determined by the processes of diffusion of dissolution (like it is in a case with the oral agents, suppositories, and transdermal patches). If clinical tests prove that the generic is significantly different from an original (such as it has a lower curative ratio, a lower solubility or takes longer to start acting), then it will also be necessary for a manufacturer to run in vivo and in vitro tests.
Benefits of generics
The advantages of generics include:
- A low cost (a generic manufacturer does not have to pay for the drug development, research, and licensing);
- Already-existing clinical trial results.
An already-gathered experience in the practical use of the drug (active ingredient) in the form of the original drug which the generic imitates.