Where do the medicines we take from chemists come from? How do the doctors know which drug is good for which disease? How the medicines really are able to cure a particular ailment they have been prescribed for? Do these questions come to your mind, whenever you buy any medicine?
Come, let us today know about the medicine development from the beginning…
The development of medicine is called a Clinical Research and has different Phases. Phases of the clinical research are the steps of experiments with a health intervention in an attempt to find enough evidence for a process which the scientists think would be helpful in medical treatment.
The pharmaceutical study starts its journey from a drug design and drug molecule discovery which further progresses into animal testing and then human studies to see the drug’s effectiveness.
Drug undergoes many trials- Preclinical, Phase 0, Phase I, II, III and IV. Sometimes combined trials also are undertaken to reduce the time of development, like Phase I/II and II/III.
When the drug molecule is identified, it undergoes many in vitro (test tube or cell culture) and in vivo (animal) experiments. These experiments are conducted to know the preliminary efficacy, toxicity, and pharmacokinetics of the various doses of the drug. Many drug molecules are designed at a time and these pre-clinical studies let the pharmaceutical companies decide which molecule has a greater potential in further studies.
Design of the Studies:
Trials are always conducted by following the set of steps, called the protocol, developed by the researchers to find the specific questions related to the medical product. Information from the prior studies become the base for the researchers to develop research questionnaire and objectives:
- Participant selection
- Number of participants
- Duration of the study
- Controlled or not
- How and what dosage will be given
- What and when the data will be collected
- Review and analysis time
Phase 0 Study
It is also called micro-dosing trials, 10-15 human subjects are taken and single sub-therapeutic doses are administered to gather the pharmacokinetic (PK) data of the drug. This enables the company in deciding to go or no go for the further Vendetta.to development of the drug, based on more relevant human data instead of animal data.
Such trials exceed the speed of promising drug development by establishing whether or not the drug acts on humans as expected in pre-clinical studies.
After the company decides to take the molecule of the drug forward in development, it will have to submit the data of its preliminary studies to the FDA called Investigational New Drug (IND) application filing.
Phase I Study
Also called First-in-man studies as these are the first stage of human testing studies. These are the studies which are designed to determine the maximum dose that can be administered without showing adverse effects.
Contract Research Organizations (CROs) conduct such studies in the clinical trial clinics where medical staff provides full-time attention to 2-100 healthy subjects enrolled for the study and collects the data.
These studies determine the safety (pharmacovigilance), tolerability, pharmacokinetics (PK)and pharmacodynamics (PD) of the drug. The design of Phase I studies is dose-ranging also called dose escalation studies conducted in controlled clinics called Central Pharmacological Units (CPUs).
Usually, healthy subjects are hired but sometimes terminally ill patients like of cancer and HIV and also those who have already tried and failed to improve on existing medications.