Preclinical development consists of the identification and validation of target proteins. To do this, the biological mechanisms involved in a particular disease must be identified and validated. Once this process has been carried out, the molecules that interact with the target proteins must be identified. And in turn optimize the properties of these molecules and see if they are safe and effective. Within this group of molecules, the molecule or molecules that have the optimal properties for development (Drug Candidate) must be selected.
Once the candidate drug has been identified, it will be documented that this compound is safe for the development of tests.
It is divided into 3 phases:
Phase I: Pharmacology
It is carried out in healthy volunteers to document drug safety, defining the maximum tolerated dose and the nature of observed adverse reactions. As well as determining pharmacokinetics) Absorption, distribution, metabolism, and excretion, and interactions
The design of these studies is uncontrolled or placebo-controlled, and single or multiple doses may be administered.
Phase II: Exploratory Therapeutics
It aims to determine the preliminary efficacy and safety in the proposed indication, as well as the most appropriate dose and regimen. The population studied are patients with strict selection criteria that make up a homogeneous sample. The design of the studies is oriented to the search for the ideal dose; they are mainly short studies.
Phase III: confirmatory therapeutic studies or ¨Pivotal Studies¨
They are designed to demonstrate and/or confirm efficacy and safety in the proposed indication in large patient populations. They also provide an adequate basis for the evaluation of the risk-benefit ratio to allow the marketing of the drug. The population studied are patients with selection criteria representative of the population suffering from the disease. These clinical trials are well controlled (Placebo or active control).
Discovery and development of new drugs is a long process, usually between ten and fifteen years from initial research to the launch of a drug on the market, including the six to eight years between Phase I clinical trials and market launch.