Before any new drug is cleared for human use, it must go through the appropriate phases and be approved by the relevant authorities. As explained by industry expert ObvioHealth, every step of the specified trials is essential because it ensures that all possible effects have been studied and mitigated as much as possible.
So how long does a clinical trial take? What is their significance? Can any of the phases be skipped or hastened? There are usually four phases to any drug trial, and they are as follows;
- Phase 1
In most cases, phase one will usually take a minimum of a few months and a maximum of one year. In this phase, there are generally between twenty and a hundred people that participate in it. The volunteers are healthy people who have gone a series of tests to ensure that they have no preexisting medical conditions and are healthy.
So why does the face require healthy persons? This is because the main focus of phase 1 is to determine the side effects of the trial drug. The other motives for this part of the trial are determining the effective dosage and how and when the patient needs to take medicine.
It is important to note that before most drugs are introduced to Phase 1, there are usually tested on animals or have been proven not lethal for humans. There is usually a seventy percent chance that most of these drugs will be approved to move to Phase 2 of the trial.
- Phase 2
Phase 2 is similar to Phase 1 in that doctors further evaluate the trial drug’s side effects. The main difference with this stage is that the drug is tested on patients who suffer the disease that doctors are trying to cure. Doctors appreciate this stage’s sensitivity, and it takes two years or more to move on to the next phase.
For the doctors to better determine the side effects and efficacy of the trial drug, there will be two groups in this stage. Both groups are of patients with the disease. The first group is monitored while taking the recommended medication, while the second group is given the recommended medication and the trial drugs.
Randomization is done to choose which patients receive the new drug. All the patients’ names are input into the computer, and it works to assign who gets the trail randomly. This process is necessary to ensure fairness and reduce the chances of biased choosing by the medical staff.
This is one of the more rigorous and thorough stages, and roughly thirty-three percent of the medications move to phase 3
- Phase 3
At this stage, the doctors have already had conclusive results from tests done in Phase 2. The side effects have been well established, and the patients have improved. In Phase 3, the doctors will compare the trial drug with the existing medication and determine which is better.
The better drug is one with fewer side effects and cures the patient in a better way. There are many volunteers involved in this part. The doctors will gather a group of people of different genders, ethnicities, and ages to determine how effective the trial drug is in other people.
They publish a report if the doctors are confident and have enough evidence to back the new drug. This informs other doctors of the new medicine and may decide to test it on patients, not in the trial.
The other step in this phase is to get approval from the relevant authorities so that it can be approved for public use. This stage will take many years, depending on how much evidence the researcher gathers on the safety and efficacy of the trial drug. When the drug is approved, it moves to phase 4.
- Phase 4
This is the final stage of most clinical trials whose trial drug has been approved by the regulatory bodies. The drug is still being monitored to see if there are any new developments with the patients that use it.
The doctors will note any long-term effects that arise, note them accordingly, and forward any concerns to the relevant authorities. If there are concerns about the new treatment, the authorities can take away the drug’s approval. This will halt the use of the new drugs until all the issues are fixed.
These are the four major phases of a clinical trial. How long it takes depends on factors such as the availability of resources and the type of disease, among others.
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