US Food and Drug Administration approval of generic versions of complex biologics: implications for the practicing physician using low molecular weight heparins

Low-molecular-weight heparins (LMWHs) have shown equivalent or superior efficacy and safety to unfractionated heparin as antithrombotic therapy for patients with acute coronary syndromes. Each approved LMWH is a pleotropic biological agent with a unique chemical, biochemical, biophysical and biological profile and displays different pharmacodynamic and pharmacokinetic profiles. As a result, LMWHs are neither equipotent in preclinical assays nor equivalent in terms of their clinical efficacy and safety. Previously, the US Food and Drug Administration (FDA) cautioned against using various LMWHs interchangeably, however recently, the FDA approved generic versions of LMWH that have not been tested in large clinical trials. This paper highlights the bio-chemical and pharmacological differences between the LMWH preparations that may result in different clinical outcomes, and also reviews the implications and challenges physicians face when generic versions of the original/innovator agents are approved for clinical use.

Morphological analysis of Mecosarthron Buquet and Xixuthrus Thomson and Reevaluation of Generic Assignment of Xixuthrus domingoensis Fisher (Coleoptera, Cerambycidae, Prioninae)

The characters defining Mecosarthron Buquet, 1840 and Xixuthrus Thomson 1864 are discussed, along with a historical review of the literature that described and classified these taxa. Through morphological examination of these genera and most of the included species, we addressed the systematic placement of Xixuthrus domingoensis Fisher, 1932 that was placed in Mecosarthron by Ivie (1985). We restore its placement in the genus Xixuthrus. The first description of the female of X. domingoensis is provided, along with comparative redescriptions of Mecosarthron gounellei (Lameere, 1903), and M. buphagus Buquet, 1840. We include a key to the species currently in Mecosarthron.