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Research and new methods

Phase IV: after approval

Phase IV follows how a medicine works in real life, in thousands of people, after it has been approved and is in use.

Last updated: ~1 min read
A pharmacist taking a box of medicine from a pharmacy shelf
Figure 1.After approval: the medicine reaches the pharmacy

01Short answer

Clinical trial participants are selected; in real life, the medicine is given to people who are older, have other illnesses or take other medicines. Phase IV picks up rare or late side effects, long-term benefit and interactions with other medicines. Doctors and patients can report side effects to the regulator. Sometimes these data lead to updated instructions or restricted use.

02Simple explanation

Real life.

Rare side effects.

Long term.

Guidance may be updated.

03Scientific explanation

NCI: phase IV trials study the long-term safety and effectiveness of an approved treatment in large numbers of people.

NCI: new treatments are tested step by step, from the laboratory to clinical trials; only those proven safe and beneficial become standard care.

04What happens in the body?

Pharmacovigilance

Ongoing monitoring of medicine safety.

A rare point
Figure 2.A rare point — Phase IV: after approval

Real-world data

Information gathered from everyday practice.

A long road
Figure 3.A long road — Phase IV: after approval

How to read the news

Research news brings hope, but not every advance suits everyone. Look at who it was tested in, at what phase and in how many people.

Talk to your doctor

Show your doctor what you have read; they will explain how it relates to your diagnosis and treatment. Do not change your treatment on your own.

05From research news to a conversation: four steps

Read, check, ask, decide together.

Read — From a trusted source.1ReadFrom a trusted source.
Check — Phase, participants, result.2CheckPhase, participants, result.
Ask — Show your doctor.3AskShow your doctor.
Decide — Together, without rushing.4DecideTogether, without rushing.
SourceA trusted site.
DoctorA personal explanation.
SafetyNot changing treatment yourself.

06Key points at a glance

TopicIn brief
PharmacovigilanceOngoing monitoring of medicine safety.
Real-world dataInformation gathered from everyday practice.
How to read the newsResearch news brings hope, but not every advance suits everyone. Look at who it was tested in, at what phase and in how many people.
Talk to your doctorShow your doctor what you have read; they will explain how it relates to your diagnosis and treatment. Do not change your treatment on your own.

07Key terms

Pharmacovigilance
Collecting and analysing side effects.
Real-world data
Data from outside clinical trials.
Clinical trial
Testing a new treatment with volunteers.
Evidence
A result confirmed by reliable research.

08Key points

  • Watch.
  • Report.
  • Update.
  • Check the source.
  • Talk to your doctor.

09Frequently asked questions

Can I report a side effect myself?

In many countries, yes; tell your doctor first.

Is an approved medicine completely safe?

Its benefits outweigh its risks, but monitoring continues.

Is this advance right for me?

Only your treating doctor can say, based on your diagnosis, stage and condition.

10Questions for your doctor

Take these questions to your appointment. The ones you save are collected on the “My questions” page and stay on this device only.

  1. Can I report a side effect myself?

  2. Is an approved medicine completely safe?

  3. Is this advance right for me?

My questions

12Sources

  1. National Cancer Institute. Phases of Clinical Trials
  2. National Cancer Institute. NCI Dictionary of Cancer Terms: phase IV clinical trial
  3. National Cancer Institute. What Are Clinical Trials?
  4. National Cancer Institute. Using Trusted Resources
  5. National Cancer Institute. NCI Dictionary of Cancer Terms: T-cell receptor
  6. National Cancer Institute. NCI Dictionary of Cancer Terms: umbilical cord blood transplantation
  7. National Cancer Institute. NCI Dictionary of Cancer Terms: conditioning regimen
  8. National Cancer Institute. NCI Dictionary of Cancer Terms: bioinformatics
  9. National Cancer Institute. NCI Dictionary of Cancer Terms: microscope
  10. National Cancer Institute. NCI Dictionary of Cancer Terms: eligibility criteria
Medical disclaimerThis information is for educational purposes only and does not replace medical advice.
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