The generation of competition in the market translates into benefits. However, the availability of generic and biocomparable drugs (also known as biosimilars) that have reduced prices does not necessarily come without additional health costs. The concept of «biosimilar», as defined internationally, implies that the molecules produced to compete with the innovator are comparable to the original biological molecules. Most of the time, differences are not in the molecular structure per se, but in the manufacturing processes (although this is not necessarily true in all cases around the world). That is of potential importance if we consider that some modifications can lead to efficacy and safety that could be different from expected. The non-comparable safety of biosimilar molecules has been studied for decades. Thus, it is essential that the production and distribution processes of non-innovator drugs are adequately monitored, so that the population can be reasonably assured that they receive quality products, and that the information derived from scientific studies applies to them and their circumstances.