Antibiotics
Antibiotics are substances produced by microorganisms that kill or inhibit the growth of other microorganisms and are typical
secondary metabolites. Most antibiotics used in human and veterinary medicine are produced by filamentous fungi or bacteria of the Actinobacteria group.
Most of the isolates obtained produce known antibiotics, but when a new antibiotic is discovered, it is produced in sufficient amounts for structural analyses and then tested for toxicity and therapeutic activity in animals. Unfortunately, most new antibiotics fail these tests. However, a few prove to be medically useful and go on to be produced commercially. The time and costs in developing a new antibiotic, from discovery to clinical usage, average 15 years and 1 billion ($US). This includes many phases of clinical trials, which alone can take several years to complete, analyze, and submit for
United States Food and Drug Administration (FDA) approval