Clinical development is the process of testing new methods of diagnosing, treating, or preventing health conditions in humans. It involves conducting clinical trials, which are experiments with a health intervention to obtain sufficient evidence for its effectiveness and safety. Clinical trials are essential for bringing new medicines, vaccines, medical devices, and diagnostic assays to the market.

Clinical trials follow a typical series of phases, from early, small-scale, Phase 1 studies to late-stage, large-scale, Phase 3 studies. Each phase has a different purpose and helps researchers answer different questions.

Phase 0

Phase 0 of a clinical trial is done with a very small number of people, usually fewer than 15. The purpose of this phase is to test whether a new medicine is safe for humans before using it in higher doses for later phases. The participants are given a very small dose of the medicine, which is unlikely to have any therapeutic effect, but may provide some information about how the medicine behaves in the human body. For example, researchers may measure how the medicine is absorbed, metabolized, and excreted by the body, or how it interacts with other medicines. If the medicine acts differently than expected, the researchers may do some additional preclinical research before deciding whether to continue the trial.

Phase 1

Phase 1 of a clinical trial involves about 20 to 80 people who have no underlying health conditions. The goal of this phase is to determine the highest dose of the medicine that humans can take without serious side effects. The participants are usually given different doses of the medicine in a controlled setting and monitored closely for any adverse reactions. The researchers also look at the best way to administer the medicine, such as orally, intravenously, or topically. According to the U.S. Food and Drug Administration (FDA), approximately 70 percent of medicines move on to phase 2.

Phase 2

Phase 2 of a clinical trial involves several hundred participants who are living with the condition that the new medicine is meant to treat. The aim of this phase is to evaluate how effective the medicine is and to gather more information about its safety and side effects. The participants are usually given the same dose that was found to be safe in phase 1, or sometimes different doses to compare their effects. The researchers compare the outcomes of the participants who receive the new medicine with those who receive a placebo (an inactive substance) or a standard treatment for the condition. The researchers also monitor the participants for several months or years to see how long the effects of the medicine last and whether there are any long-term risks. According to the FDA, approximately 33 percent of medicines move on to phase 3.

Phase 3

Phase 3 of a clinical trial involves several thousand participants who have the same condition as in phase 2. The objective of this phase is to confirm the effectiveness and safety of the new medicine and to compare it with other available treatments. The participants are randomly assigned to receive either the new medicine or a placebo or a standard treatment in a double-blind manner, meaning that neither they nor the researchers know who receives what. The researchers collect data on various outcomes, such as symptoms, quality of life, survival, and adverse events. The results of phase 3 trials are usually the basis for regulatory approval of a new medicine by authorities such as the FDA or the European Medicines Agency (EMA).

Phase 4

Phase 4 of a clinical trial is also known as post-marketing surveillance or pharmacovigilance. It takes place after a new medicine has been approved by regulatory authorities and is available for use by the general population. The purpose of this phase is to monitor the long-term effects and safety of the new medicine in real-world settings and to detect any rare or unexpected adverse events that may not have been observed in earlier phases. The participants are anyone who seeks treatment from their physicians and receives the new medicine as part of their routine care. The researchers collect data from various sources, such as electronic health records, registries, surveys, or spontaneous reports from health professionals or patients.

Clinical development is a complex and rigorous process that requires careful planning, execution, and analysis. It can take many years and cost millions of dollars to complete. However, it is also a vital process that ensures that new medicines are safe and effective for human use and can improve health outcomes for millions of people.

Regulators

If you are interested in the process of drug development and approval, you might wonder who are the authorities that regulate and oversee this complex and rigorous process. In this blog post, we will introduce some of the major regulatory agencies around the world that are responsible for approving new medicines and ensuring their safety, efficacy and quality.

The United States Food and Drug Administration (FDA)

The FDA is the federal agency that regulates the development, manufacture, marketing and distribution of drugs, biologics, medical devices, food, cosmetics and tobacco products in the United States. The FDA’s Center for Drug Evaluation and Research (CDER) is the division that reviews and approves new drugs for human use. CDER evaluates the scientific data and clinical trial results submitted by drug sponsors, and determines whether the benefits of a new drug outweigh its risks. CDER also monitors the safety of drugs after they are approved and on the market, and can take actions such as issuing warnings, requiring label changes or withdrawing a drug from the market if new safety issues arise.

The European Medicines Agency (EMA)

The EMA is the agency that regulates the development, evaluation, authorization and supervision of medicines for human and veterinary use in the European Union (EU) and the European Economic Area (EEA). The EMA works with national regulatory authorities from the EU member states, as well as Iceland, Liechtenstein and Norway, to ensure a harmonized approach to drug regulation across Europe. The EMA’s Committee for Medicinal Products for Human Use (CHMP) is the body that gives scientific opinions on whether a new drug should be authorized for marketing in the EU. The CHMP bases its opinions on the assessment reports prepared by national authorities, as well as its own scientific evaluation. The final decision on whether to grant a marketing authorization for a new drug in the EU is made by the European Commission.

The National Medical Products Administration (NMPA)

The NMPA is the agency that regulates the development, registration, production, distribution and use of drugs, medical devices and cosmetics in China. The NMPA’s Center for Drug Evaluation (CDE) is the division that reviews and approves new drugs for human use. CDE evaluates the quality, safety and efficacy of new drugs based on the data and documents submitted by drug applicants, and issues approval documents or rejection notices. CDE also supervises the post-marketing safety of drugs and can take measures such as suspending or revoking a drug approval if serious adverse events occur.

These are just some examples of the authorities that are responsible for approving new medicines in different regions of the world. There are many other regulatory agencies that have similar roles and functions in other countries or regions, such as Health Canada, Therapeutic Goods Administration (TGA) in Australia, Pharmaceuticals and Medical Devices Agency (PMDA) in Japan, Medicines Control Council (MCC) in South Africa, etc. The regulatory standards and requirements may vary from one agency to another, but they all share a common goal: to protect public health by ensuring that only safe, effective and high-quality medicines are available to patients.