Drug development techniques

The complexities involved in NDD have increased in the past 5 years. This has occurred as the result of enhanced drug development techniques and global registration attempts. Spurred also by the effort to maximize profits, this phenomenon has placed the Quality process under increased and manifold stress. The QA and QC processes are placed in the forefront by any major drug development organization. The efforts of QA will be reviewed in this chapter. 

Gupta, P.K. Brazeau, G.A. Injectable Drug Development Techniques to Reduce Pain and Irritation Interpharm Press Denver, CO, 1999. 

Recent developments in drug discovery and drug development spurred the need for novel analytical techniques and methods. In the last decade, the biopharmaceutical industry set the pace for this demand. The nature of the industry required that novel techniques should be simple, easily applicable, and of high resolution and sensitivity. It was also required that the techniques give information about the composition, structure, purity, and stability of drug candidates. Biopharmaceuticals represent a wide variety of chemically different compounds, including small organic molecules, nucleic acids and their derivatives, and peptides and proteins. 

Molecular properties may be defined as those material characteristics which theoretically could be measured for a small ensemble of individual molecules. Due to the minimal sample requirements, molecular properties can be determined at the earliest stages of drug development. Though the molecular level techniques... 

The two methods are complementary in that each can provide information inaccessible to the other. When these techniques are used in conjunction, substantial characterization of a solid material becomes possible. This information can be extremely useful during the early stages of drug development, since only a limited amount of the drug candidate is normally available at that time. 

In summary, TLC analysis plays a critical role in the drug development process. Many instruments are available, and the technique is used for both quantitative and qualitative testing. i f determination, identity testing, and stability testing are just a few ways to utilize TLC. 

Both plate reader and mass spectrometry based methods are commonly used for screening. The selection of a technique depends on instrument availability, throughput needs and the stage of compound advancement. For the characterization of compounds in drug development and clinical candidates, assays carried out using drug-like probes and analyzed by LC-MS/MS methods are considered the gold standard [117]. 

The book is separated into five major sections One short section on general aspects of spectroscopy, molecular biology and data evaluation is followed by an introduction into the NMR of commonly encountered classes of biomolecules. Thereafter, recent developments in spectroscopic techniques are highlighted. The next section describes experiments and practical aspects useful for the characterization of protein-ligand interactions. The final section presents an account on strategies for drug development using NMR written by experts from pharmaceutical industry. 

Recently, it has been possible to grow cells of the human immune system in special mice. These mice carry a genetic defect called severe combined immunodeficiency (SCID), which leaves them with crippled immune systems, much like those in AIDS patients. Because SCID mice lack functional cellular immunity, it is possible to implant them with human cells without tissue rejection taking place. Researchers have recently developed techniques to implant human fetal tissues containing stem cells for the blood into SCID mice. It is then possible to reconstitute these mice with functional human immune system cells, including T lymphocytes and B lymphocytes. They have also found that if these SCID mice are infected by HIV, the virus will establish infection in the human tissue and destroy the T helper lymphocytes, just as it does in humans. Thus, it may be possible to study some of the mechanisms by which HIV attacks the immune system in these mice. In addition, they may be very useful for testing potential antiviral drugs. 

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