Phases of Drug Development
Drug Development Phases in Clinical Research Trials
Drug discovery may occur by massive screening of high throughput assays of plant, marine and bacterial extracts testing their effect on inhibiting tumor growth in cell cultures. When a chemical extract is purified, identified and tested successfully in a mouse model, then a company may patent the purification process and the new experimental agent. This research phase is often referred to as “drug discovery” or preclinical or basic science research.
Over the past few years, modern drugs have been engineered instead of discovered for specific targets using computer software assisted molecular models, known as “target discovery and drug design”. Promising drug candidates then enter preclinical testing on tumor cell cultures. If it stops tumor growth in cell culture, it then moves into testing in mice with transplanted tumors (drug development diagram attached). If the experimental agent is effective at controlling tumors in mice, then it’s safety is further tested in primates. Due to safety and efficacy concerns, fewer than one in a hundred potential drugs progress to primate testing.
Once a pharmaceutical company decides to carry an experimental agent into human testing it must apply for an Investigational New Drug Application (IND) through the FDA. Before the experimental drug may be administered to humans, the pharmaceutical company must manufacture the compound according to Current Good Manufacturing Process (cGMP) with an FDA approved facility inspection. Sponsored by a pharmaceutical company, INDs are submitted by a Principle Investigator to the FDA’s Center for Drug Evaluation and Research (CDER) for approval to administer to human subjects on a phase I trial. If the drug is a biologic such as a vaccine, cellular, blood, tissue, gene, or viral product then the IND is submitted to the FDA’s Center for Biologics Evaluation and Research (CBER) for approval prior to the first Phase I human trial. Biologic drugs are manufactured according to Current Good Tissue Practice (cGTP) in a FDA inspected and approved cell processing facility.
|
