A clinical trial is a scientific examination in which a new medicine is administered to humans, with or without an illness, to determine the safety and efficacy of the drug in treating the disease.

Clinical trials, also known as clinical development or clinical studies, involve the participation of human participants.

Establishing the efficacy and safety of new treatments, including as pharmaceuticals, drug combinations, alternative forms of therapy such as surgery, and preventative medicines like as vaccinations.

Once a treatment has been shown successful in the laboratory utilising cell or tissue culture systems or model organisms, only then are clinical trials conducted (Stage 3 of drug development).

Current clinical trials are the most effective method for determining which novel medicines are beneficial to human health.

In clinical trials, participants are typically separated into two or more groups. The majority of clinical studies are randomised, which means that participants are randomly assigned to treatment groups.

Randomization ensures that participants do not know whether they are receiving the medicine under research or a placebo, also known as a blinded experiment.

In certain instances, not even the investigators (scientists, physicians, etc.) know who is receiving the medicine under investigation until the very last moment.

This is a double-blind experiment that ensures neither patients nor researchers are influencing the outcome of the clinical trial with their preconceived notions.

Randomization also helps to decrease the variances between the groups by distributing individuals with specific qualities in an equal manner.

Always one of the groups is a control group. This is the benchmark by which the efficacy of the new treatment is measured.

In the control group, participants may receive no medication at all, known as a placebo, or the current standard treatment for the disease being studied.

If the control group does not receive an active medicine, a placebo is frequently administered. Typically, this is a medication that visually mimics the experimental medicine, but contains no active drug and so has no effect on the patient.

Important because they permit double-blind clinical trials to be conducted.

Under double-blind settings, neither the volunteers nor the clinical researchers are aware of who is taking the medicine until the conclusion of the study. This eliminates bias and contributes to the production of fair and objective outcomes.

In a clinical study, there are typically four essential phases, but occasionally there might be five:

Typically, trials proceed directly to Phase I, but occasionally a Phase 0 investigation is conducted. A very small group of participants are administered a very modest amount of a medication during Phase 0.

Phase 0

Phase 0 seeks to determine: whether the medication reaches its intended target, such as cancer; how the drug behaves in the body; and how target cells in the body, such as cancer cells, respond to the treatment.

The primary objective of Phase 0 is to accelerate the development of potential new medications. Human testing of some medications at extremely low dosages provides a sharper picture of drug-target interactions than testing on model species.

In Phase I trials, a modest number of healthy volunteers are involved. They are designed to assess the safety of the new treatment in order to determine whether or not it creates adverse effects. In the case of new medications, a safe dose range is determined, and any potential adverse effects are recognised. Typically, this phase lasts a few months.

Phase I

Phase II involves a higher number of individuals than Phase I. In Phase II, these individuals have the condition targeted by the treatment. This phase is intended to evaluate the efficacy of the new medicine in treating the condition. Typically, these investigations are randomised and double-blind to assure objectivity. These investigations might take up to two years.

Phase II

These trials are comparable to Phase II trials, but are conducted with hundreds or thousands of individuals. They collect vast quantities of information regarding the treatment's safety and efficacy. After completion of these trials, the treatment may be licenced for widespread usage. This stage could last several years.

Phase III

This phase consists of post-marketing studies. It utilises medical practitioner input to assess the treatment's long-term safety. It is utilised to learn more about the drug's side effects and safety. It enhances comprehension of the dangers and benefits of the treatment over the long run. It demonstrates how effectively the medicine performs when used more widely.

Phase IV