Preclinical drug testing

In early preclinical drug testing, it is preferable to use right from the beginning excipients that can and will be used in later development phases. Whenever possible, the formulation principle and the excipients should be used consistently throughout the preclinical testing. 

Keywords Microstructuring of polycarbonate, engineering of scaffolds, microthermoforming, organotypic cell culture, preclinical drug testing, 3D cell culture, biomimetic structures... 

True zwitterionic compounds are rare among drugs. The oral absorption of truly zwitterionic compounds is poor unless the compound is a substrate for an absorptive biological transporter as in an a-amino acid which is a substrate for the PepTl nutrient transporter. The aqueous solubility of a true zwitterionic compound will be at a minimum at the isoelectric point which unfortunately for many compounds happens close to the neutral pH at which oral absorphon occurs. Species extrapolation predicting oral absorphon and pk/pD from preclinical animal tests to man are difficult for zwitterions. 

Preclinical drug development also involves animal testing [61]. Data from one rodent species and one nonrodent species are usually collected to determine the absorption, metabolism, and toxicity characteristics of the compound. Both short-term (2 weeks to 3 months) and long-term (up to several years) studies are done. The long-term studies are particularly useful for... 

Chapman K et al (2007) Preclinical safety testing of monoclonal antibodies the significance of species relevance. Nat Rev Drug Discov 6 120-126... 

Preclinical drug development involves understanding of dosage, formulation, and route of administration, typically in animal models, so that safe and effective doses for human administration can be estimated. The drug development phase extends from prechnical assessment through clinical testing. 

The development of a new drug involves extensive preclinical (animal) and clinical (human) studies.19,21 The basic procedure for testing a new drug is outlined here and is summarized in Table 1-2. Details about the phases of drug testing can also be found on the FDA website (http //www.fda.gov/cder/handbook). 

Drug discovery requires a host of inputs, new ideas, design and synthesis of substances, evaluation of preclinical toxicity tests in animals, clinical studies in human volunteers, permission to market the drug, postmarketing studies of safety, and comparison with other medicines. Drug development is highly technical and enormously expensive, with a success rate of 1 in 10,000 compounds. 

Review preclinical/animal testing and plan for Approve to test the drug candidate in humans... 

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