A group of Dutch researchers have reported that about one fourth of the biological drugs that had hit the United States and Europe markets since 1995 had given rise to concerns about their safety just a few years after they had been approved.

Derived from living cells (and not from various chemicals like the typical drugs are), the biological meds have prompted safety warnings with regards to immune system disorders, infusion reactions, infections and cancer risk.

Biologicals, as they are also called, help treat medical conditions such as anemia, rheumatoid arthritis, hepatitis and cancer, the mainstay method of administration being via injections.

Researchers at the Utrecht University in the Netherlands, led by Thijs Giezen, investigated regulatory actions that had been taken concerning the biological drugs’ safety issues, taking into account meds that had been approved by the United States or the European Union over a period of twelve years, from January 1995 to June 2007. The regulatory actions regarded 174 such biologicals, of which 41 were found to have been the object of the aforementioned safety-related measures since June last year.

The team published their conclusions in the Journal of the American Medical Association, stating that the regulatory actions entailed adding a warning to the products’ labels, which notified of the possible harmful effects that might come from using the drugs.

Results of the study also showed that 71 percent of the relabeling took place approximately five years after the approval of the drug, with the average time between the biologicals release on the market and the regulatory action concerning it having been reported at three and a half years.