Drug development process

By: Ph. Mohammad Al Roomi


The drug development process is a set of thoroughly designed steps from the discovery of a lead compound to the end-market product that ensures the best safety and efficacy combination for each consumer and is regulated by the American Food and Drug Association (FDA). These steps are:


Step 1: Discovery and development

In this step the researchers discover new drugs through studying the disease process or test a new molecular compound and also review the previous treatment methods in order to minimize the amount of unwanted effects and better optimize the product. At this stage many compounds may be potential candidates for developing a new medical treatment.

After identifying a promising compound, experiments are conducted in order to gather more information about:

  • ADME (Absorption, Distribution, Metabolism, Excretion)
  • MOA (mechanism of action) and benefits
  • Optimal Dosage
  • Optimal Route of administration
  • Side-effects
  • The effect of different variables (Race, Gender, Ethnicity, etc..)


Step 2: Preclinical Research:

In this step the drugs mainly undergo laboratory and animal testing in order to get detailed information on dosing and toxicity levels. After preclinical testing, researchers review their findings and decide whether the drug should be tested on human subjects.


Step 3: Clinical Research or clinical trials:

Clinical Research or Clinical Trials is the first step which involves the participation of human subjects and the gathering of the drug or compound effect on the human body. However, before starting the clinical trials the developers must begin the Investigational New Drug Process (IND).  In this process an application is submitted to FDA which includes:

  • Animal study data and toxicity data
  • Manufacturing information.
  • Clinical protocols (study plans) for studies to be conducted.
  • Data from any prior human research.
  • Information about the investigator.

The submission of the application is followed by 30 days of study period to give either the approval for the next stage or the denial and termination of study, which is rare. This approval process gives protection to the human volunteers against any significant harm that may accompany this drug. After the approval is given, trials begin and are divided into three phases and if the treatment is successful in one phase it moves to the next phase. The first phase consists of a small number of healthy human volunteers or diseased volunteers of 20 to 100 subjects and this phase mainly takes several months. The drug safety and dosage will be thoroughly studied and 70% of drugs move on to the next phase. Phase two trials consist of hundreds of patients with a disease that the drug is intended to affect and will be studying the efficacy and side-effects of the drug and will take months to 2 years of study. Approximately 33% of drugs move on to the next stage, which is Phase three. The Final Phase is much larger and broader and consists of 300-3000 diseased volunteers and will also monitor the drug’s efficacy and side effects and this phase will take from 1 year to 4 years of research and study.


Step 4: FDA Review

If a drug developer has evidence from its early tests and preclinical and clinical research that a drug is safe and effective for its intended use, the company can file a New Drug Application (NDA) to market the drug. In the NDA, a drug developer must include everything about a drug—from preclinical data to Phase 3 trial data. Developers must include reports on all studies, data, and analyses. Along with clinical results, developers must include:

  • Proposed labeling
  • Safety updates
  • Drug abuse information
  • Patent information
  • Any data from studies that may have been conducted outside the United States
  • Institutional review board compliance information
  • Directions for use

A thorough examination of the submitted data and analytics and a decision is given to the team of developers to approve or disapprove the drug marketing for the public.


Step 5: FDA Post-Market Safety Monitoring:

Even though clinical trials provide important information on a drug’s efficacy and safety, it is impossible to have complete information about the safety of a drug at the time of approval. Despite the rigorous steps in the process of drug development, limitations exist. Therefore, the true picture of a product’s safety actually evolves over the months and even years that make up a product’s lifetime in the marketplace. FDA reviews reports of problems with prescription and over-the-counter drugs, and can decide to add cautions to the dosage or usage information, as well as other measures for more serious issues.