An Expert Report on Human Thrombin (DB11571): A Plasma-Derived Topical Hemostatic Agent

I. Biochemical Profile and Pharmaceutical Formulation of Human Thrombin

1.1. Identification, Nomenclature, and Classification

Human thrombin is a highly purified, protein-based biotech therapeutic agent central to the process of hemostasis.[1] It is identified by the DrugBank Accession Number DB11571 and the Chemical Abstracts Service (CAS) Number 9002-04-4.[1] As a fundamental enzyme in the coagulation cascade, it is known by a variety of synonyms that reflect its biological function and origin, including Thrombin (human), Thrombin human plasma-derived, Trombina humana, Coagulation Factor IIa, fibrinogenase, and thrombofort.[1]

Biochemically, human thrombin is classified as a highly specific, endolytic serine protease belonging to the S1 (trypsin) family of enzymes.[1] It is encoded in the human genome by the F2 gene and is also categorized as a platelet activating factor due to its potent effects on platelet aggregation.[1] Its enzymatic activity is cataloged under the Enzyme Commission (EC) number 3.4.21.5.[4] This precise classification underscores its role as a targeted biological catalyst, distinct from small-molecule drugs, and places it within a well-understood family of proteolytic enzymes.

1.2. Source and Manufacturing: From Pooled Plasma to Purified Protein

The primary source material for therapeutic human thrombin is pooled human plasma, collected from carefully screened donors.[1] This origin is a critical feature that distinguishes it from two other classes of therapeutic thrombin: bovine-derived thrombin, which is purified from cow plasma, and recombinant thrombin (thrombin alfa), which is produced using recombinant DNA technology in a genetically modified Chinese Hamster Ovary (CHO) cell line.[1]